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  • 1.
    Abate, Ebba
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. University of Gondar, Ethiopia.
    Belayneh, Meseret
    University of Addis Ababa, Ethiopia.
    Idh, Jonna
    Vastervik Hospital, Sweden.
    Diro, Ermias
    University of Gondar, Ethiopia.
    Elias, Daniel
    University of Southern Denmark, Denmark.
    Britton, Sven
    Karolinska Hospital, Sweden.
    Aseffa, Abraham
    Armauer Hansen Research Institute, Ethiopia.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Kalmar County Hospital, Sweden.
    Asymptomatic Helminth Infection in Active Tuberculosis Is Associated with Increased Regulatory and Th-2 Responses and a Lower Sputum Smear Positivity2015In: PLoS Neglected Tropical Diseases, ISSN 1935-2727, E-ISSN 1935-2735, Vol. 9, no 8, article id e0003994Article in journal (Refereed)
    Abstract [en]

    Background The impact of intestinal helminth infection on the clinical presentation and immune response during active tuberculosis (TB) infection is not well characterized. Our aim was to investigate whether asymptomatic intestinal helminth infection alters the clinical signs and symptoms as well as the cell mediated immune responses in patients with active TB.

    Methodology Consecutive, newly diagnosed TB patients and healthy community controls (CCs) were recruited in North-west Ethiopia. TB-score, body mass index and stool samples were analyzed. Cells from HIV-negative TB patients (HIV-/TB) and from CCs were analyzed for regulatory T-cells (Tregs) and cytokine responses using flow cytometry and ELISPOT, respectively.

    Results A significantly higher ratio of helminth co-infection was observed in TB patients without HIV (Helm+/HIV-/TB) compared to HIV negative CCs, (40% (121/306) versus 28% (85/306), p = 0.003). Helm+/HIV-/TB patients showed significantly increased IL-5 secreting cells compared to Helm-/HIV-/TB (37 SFU (IQR:13-103) versus 2 SFU (1-50); p = 0.02, n = 30). Likewise, levels of absolute Tregs (9.4 (3.2-16.7) cells/mu l versus 2.4 (1.1-4.0) cells/mu l; p = 0.041) and IL-10 secreting cells (65 SFU (7-196) versus 1 SFU (0-31); p = 0.014) were significantly higher in Helm+/HIV-/TB patients compared to Helm-/HIV-/TB patients. In a multivariate analysis, a lower rate of sputum smear positivity for acid fast bacilli, lower body temperature, and eosinophilia were independently associated with helminth infection in TB patients.

    Conclusions Asymptomatic helminth infection is associated with increased regulatory T-cell and Th2-type responses and a lower rate of sputum smear positivity. Further studies are warranted to investigate the clinical and immunological impact of helminth infection in TB patients.

  • 2.
    Abrahamsson, Annelie
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Rzepecka, Anna
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Radiology in Linköping.
    Dabrosin, Charlotta
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Oncology.
    Equal Pro-inflammatory Profiles of CCLs, CXCLs, and Matrix Metalloproteinases in the Extracellular Microenvironment In Vivo in Human Dense Breast Tissue and Breast Cancer2018In: Frontiers in Immunology, ISSN 1664-3224, E-ISSN 1664-3224, Vol. 8, article id 1994Article in journal (Refereed)
    Abstract [en]

    The inflammatory microenvironment affects breast cancer progression. Proteins that govern the inflammatory response are secreted into the extracellular space, but this compartment still needs to be characterized in human breast tissues in vivo. Dense breast tissue is a major risk factor for breast cancer by yet unknown mechanisms and no non-toxic prevention for these patients exists. Here, we used the minimal invasive technique of microdialysis for sampling of extracellular proteins in live tissues in situ in breast cancers of women before surgery and in healthy women having dense or non-dense breast tissue on mammography. Proteins were profiled using a proximity extension assay. Out of the 32 proteins assessed, 26 exhibited similar profiles in breast cancers and dense breast tissues; CCL-4, -7, -8, -11, -15, -16, -22, -23, and -25, CXCL-5, -8, -9, -16 as well as sIL-6R, IL-18, vascular endothelial growth factor, TGF-a, fibroblast growth factor 19, matrix metalloproteinase (MMP)-1, -2, -3, and urokinase-type plasminogen activator were all increased, whereas CCL-3, CX3CL1, hepatocyte growth factor, and MMP-9 were unaltered in the two tissues. CCL-19 and -24, CXCL-1 and -10, and IL-6 were increased in dense breast tissue only, whereas IL-18BP was increased in breast cancer only. Our results provide novel insights in the inflammatory microenvironment in human breast cancer in situ and define potential novel therapeutic targets. Additionally, we show previously unrecognized similarities of the pro-inflammatory microenvironment in dense breast tissue and breast cancer in vivo suggesting that anti-inflammatory breast cancer prevention trials for women with dense breast tissue may be feasible.

  • 3.
    Abrahamsson, Thomas
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping.
    Jakobsson, H.E.
    Karolinska Institute, Stockholm, Sweden.
    Andersson, A.F.
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Björksten, B.
    Karolinska Institute, Stockholm, Sweden; Örebro University, Sweden .
    Engstrand, L.
    Karolinska Institute, Stockholm, Sweden; KTH Royal Institute of Technology, Stockholm, Sweden.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Low gut microbiota diversity in early infancy precedes asthma at school age2014In: Clinical and Experimental Allergy, ISSN 0954-7894, E-ISSN 1365-2222, Vol. 44, no 6, p. 842-850Article in journal (Refereed)
    Abstract [en]

    BACKGROUND:

    Low total diversity of the gut microbiota during the first year of life is associated with allergic diseases in infancy, but little is known how early microbial diversity is related to allergic disease later in school age.

    OBJECTIVE:

    To assess microbial diversity and characterize the dominant bacteria in stool during the first year of life in relation to the prevalence of different allergic diseases in school age, such as asthma, allergic rhinoconjunctivitis (ARC) and eczema.

    METHODS:

    The microbial diversity and composition was analysed with barcoded 16S rDNA 454 pyrosequencing in stool samples at 1 week, 1 month and 12 months of age in 47 infants which were subsequently assessed for allergic disease and skin prick test reactivity at 7 years of age (ClinicalTrials.gov ID NCT01285830).

    RESULTS:

    Children developing asthma (n = 8) had a lower diversity of the total microbiota than non-asthmatic children at 1 week (P = 0.04) and 1 month (P = 0.003) of age, whereas allergic rhinoconjunctivitis (n = 13), eczema (n = 12) and positive skin prick reactivity (n = 14) at 7 years of age did not associate with the gut microbiota diversity. Neither was asthma associated with the microbiota composition later in infancy (at 12 months). Children having IgE-associated eczema in infancy and subsequently developing asthma had lower microbial diversity than those that did not. There were no significant differences, however, in relative abundance of bacterial phyla and genera between children with or without allergic disease.

    CONCLUSION AND CLINICAL RELEVANCE:

    Low total diversity of the gut microbiota during the first month of life was associated with asthma but not ARC in children at 7 years of age. Measures affecting microbial colonization of the infant during the first month of life may impact asthma development in childhood.

  • 4.
    Abrahamsson, Thomas
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center of Paediatrics and Gynaecology and Obstetrics, Department of Paediatrics in Linköping. University of Toronto, Canada.
    You Wu, Richard
    University of Toronto, Canada.
    Jenmalm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Gut microbiota and allergy: the importance of the pregnancy period2015In: Pediatric Research, ISSN 0031-3998, E-ISSN 1530-0447, Vol. 77, no 1, p. 214-219Article, review/survey (Refereed)
    Abstract [en]

    Limited microbial exposure is suggested to underlie the increase of allergic diseases in affluent countries, and bacterial diversity seems to be more important than specific bacteria taxa. Prospective studies indicate that the gut microbiota composition during the first months of life influences allergy development, and support the theory that factors influencing the early maturation of the immune system might be important for subsequent allergic disease. However, recent research indicates that microbial exposure during pregnancy may be even more important for the preventative effects against allergic disease. This review gives a background of the epidemiology, immunology, and microbiology literature in this field. It focuses on possible underlying mechanisms such as immune-regulated epigenetic imprinting and bacterial translocation during pregnancy, potentially providing the offspring with a pioneer microbiome. We suggest that a possible reason for the initial exposure of bacterial molecular patterns to the fetus in utero is to prime the immune system and/or the epithelium to respond appropriately to pathogens and commensals after birth.

  • 5.
    Adua, Eric
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Oteng Danso, Frank
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Mensah Boa-Amponsem, Oswald
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Adusei-Mensah, Frank
    University of Cape Coast, Ghana.
    Effect of Neutrophils on Nitric Oxide Production from Stimulated Macrophages2015In: Iranian Journal of Immunology, ISSN 1735-1383, E-ISSN 1735-367X, Vol. 12, no 2, p. 94-103Article in journal (Refereed)
    Abstract [en]

    Background: During the initial phase of an infection, there is an upregulation of inducible nitric oxide synthase in the macrophages for the production of nitric oxide. This is followed by the recruitment of polymorphonuclear leukocytes (neutrophils) which release arginase. Arginase competes with inducible nitric oxide synthase for a common substrate L-arginine. Objective: To investigate whether the entry of neutrophils and release of arginase can interfere with nitric oxide production from stimulated mouse macrophages. Methods: Neutrophils were isolated from human blood and stimulated with cytodex-3 beads. Cultured macrophages were stimulated with lipopolysaccharide and interferon gamma with or without N (G)-nitro-L-arginine methyl ester or N (omega)-hydroxy-nor-L-arginine. Measurement of NO2-/NO3- and urea were done using the spectrophotometer. Results: A significantly higher level of nitric oxide production from stimulated macrophages was observed compared to control. There was a decrease in nitric oxide production when stimulated macrophages were treated with the supernatant from activated neutrophils (pless than0.05). Conclusion: Arginase from neutrophils can modulate nitric oxide production from activated macrophages which may affect the course of infection by intracellular bacteria.

  • 6.
    Ahlstrom, Christina A.
    et al.
    US Geol Survey, AK 99508 USA.
    Bonnedahl, Jonas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Kalmar Cty Hosp, Sweden.
    Woksepp, Hanna
    Kalmar Cty Hosp, Sweden.
    Hernandez, Jorge
    Uppsala Univ, Sweden.
    Olsen, Bjorn
    Uppsala Univ, Sweden.
    Ramey, Andrew M.
    US Geol Survey, AK 99508 USA.
    Acquisition and dissemination of cephalosporin-resistant E.coli in migratory birds sampled at an Alaska landfill as inferred through genomic analysis2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 7361Article in journal (Refereed)
    Abstract [en]

    Antimicrobial resistance (AMR) in bacterial pathogens threatens global health, though the spread of AMR bacteria and AMR genes between humans, animals, and the environment is still largely unknown. Here, we investigated the role of wild birds in the epidemiology of AMR Escherichia coli. Using next-generation sequencing, we characterized cephalosporin-resistant E. coli cultured from sympatric gulls and bald eagles inhabiting a landfill habitat in Alaska to identify genetic determinants conferring AMR, explore potential transmission pathways of AMR bacteria and genes at this site, and investigate how their genetic diversity compares to isolates reported in other taxa. We found genetically diverse E. coli isolates with sequence types previously associated with human infections and resistance genes of clinical importance, including blaCTX-M and blaCMY. Identical resistance profiles were observed in genetically unrelated E. coli isolates from both gulls and bald eagles. Conversely, isolates with indistinguishable core-genomes were found to have different resistance profiles. Our findings support complex epidemiological interactions including bacterial strain sharing between gulls and bald eagles and horizontal gene transfer among E. coli harboured by birds. Results suggest that landfills may serve as a source for AMR acquisition and/or maintenance, including bacterial sequence types and AMR genes relevant to human health.

  • 7.
    Aira, Naomi
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Andersson, Anna-Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Singh, Susmita K.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Mckay, Derek M.
    University of Calgary, Canada.
    Blomgran, Robert
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Species dependent impact of helminth-derived antigens on human macrophages infected with Mycobacterium tuberculosis: Direct effect on the innate anti-mycobacterial response2017In: PLoS Neglected Tropical Diseases, ISSN 1935-2727, E-ISSN 1935-2735, Vol. 11, no 3, article id e0005390Article in journal (Refereed)
    Abstract [en]

    Background In countries with a high prevalence of tuberculosis there is high coincident of helminth infections that might worsen disease outcome. While Mycobacterium tuberculosis (Mtb) gives rise to a pro-inflammatory Th1 response, a Th2 response is typical of helminth infections. A strong Th2 response has been associated with decreased protection against tuberculosis. Principal findings We investigated the direct effect of helminth-derived antigens on human macrophages, hypothesizing that helminths would render macrophages less capable of controlling Mtb. Measuring cytokine output, macrophage surface markers with flow cytometry, and assessing bacterial replication and phagosomal maturation revealed that antigens from different species of helminth directly affect macrophage responses to Mtb. Antigens from the tapeworm Hymenolepis diminuta and the nematode Trichuris muris caused an anti-inflammatory response with M2-type polarization, reduced macrophage phagosome maturation and ability to activate T cells, along with increased Mtb burden, especially in T. muris exposed cells which also induced the highest IL-10 production upon co-infection. However, antigens from the trematode Schistosoma mansoni had the opposite effect causing a decrease in IL-10 production, M1-type polarization and increased control of Mtb. Conclusion We conclude that, independent of any adaptive immune response, infection with helminth parasites, in a species-specific manner can influence the outcome of tuberculosis by either enhancing or diminishing the bactericidal function of macrophages.

  • 8.
    Ajileye, Adebisi
    et al.
    Birmingham Heartlands Hospital, England.
    Alvarez, Nataly
    Corp Invest Biol, Colombia; University of Pontificia Bolivariana, Colombia.
    Merker, Matthias
    Research Centre Borstel, Germany; German Centre Infect Research, Germany.
    Walker, Timothy M.
    University of Oxford, England.
    Akter, Suriya
    Institute Trop Med, Belgium.
    Brown, Kerstin
    Birmingham Heartlands Hospital, England.
    Moradigaravand, Danesh
    Wellcome Trust Sanger Institute, England.
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Kalmar County Hospital, Sweden.
    Andres, Soenke
    Research Centre Borstel, Germany.
    Schleusener, Viola
    Research Centre Borstel, Germany.
    Omar, Shaheed V.
    Centre TB, South Africa.
    Coll, Francesc
    London School Hyg and Trop Med, England.
    Huang, Hairong
    Capital Medical University, Peoples R China.
    Diel, Roland
    University Hospital, Germany.
    Ismail, Nazir
    Centre TB, South Africa.
    Parkhill, Julian
    Wellcome Trust Sanger Institute, Hinxton, United Kingdom.
    de Jong, Bouke C.
    Institute Trop Med, Belgium.
    Peto, Tim E. A.
    University of Oxford, England.
    Crook, Derrick W.
    University of Oxford, England; Public Health England Microbiol Serv, England.
    Niemann, Stefan
    Research Centre Borstel, Germany; German Centre Infect Research, Germany.
    Robledo, Jaime
    Corp Invest Biol, Colombia; University of Pontificia Bolivariana, Colombia.
    Grace Smith, E.
    Birmingham Heartlands Hospital, England.
    Peacock, Sharon J.
    Wellcome Trust Sanger Institute, England; London School Hyg and Trop Med, England; University of Cambridge, England.
    Koeser, Claudio U.
    University of Cambridge, England.
    Some Synonymous and Nonsynonymous gyrA Mutations in Mycobacterium tuberculosis Lead to Systematic False-Positive Fluoroquinolone Resistance Results with the Hain GenoType MTBDRsl Assays2017In: Antimicrobial Agents and Chemotherapy, ISSN 0066-4804, E-ISSN 1098-6596, Vol. 61, no 4, article id e02169-16Article in journal (Refereed)
    Abstract [en]

    In this study, using the Hain GenoType MTBDRsl assays (versions 1 and 2), we found that some nonsynonymous and synonymous mutations in gyrA in Mycobacterium tuberculosis result in systematic false-resistance results to fluoroquinolones by preventing the binding of wild-type probes. Moreover, such mutations can prevent the binding of mutant probes designed for the identification of specific resistance mutations. Although these mutations are likely rare globally, they occur in approximately 7% of multidrug-resistant tuberculosis strains in some settings.

  • 9.
    Balcha, Taye T.
    et al.
    Lund University, Sweden Minist Heatlh, Ethiopia .
    Sturegard, Erik
    Clin Microbiol Regional and University of Labs, Sweden .
    Winqvist, Niclas
    Lund University, Sweden Regional Department Infect Disease Control and Prevent, Sweden .
    Skogmar, Sten
    Lund University, Sweden .
    Reepalu, Anton
    Lund University, Sweden .
    Habtamu Jemal, Zelalem
    Oromia Health Bur, Ethiopia .
    Tibesso, Gudeta
    Columbia University, Ethiopia .
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Department of Clinical Microbiology and Infectious diseases, Kalmar County Hospital, Sweden.
    Bjorkman, Per
    Lund University, Sweden .
    Intensified Tuberculosis Case-Finding in HIV-Positive Adults Managed at Ethiopian Health Centers: Diagnostic Yield of Xpert MTB/RIF Compared with Smear Microscopy and Liquid Culture2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 1, p. 85478-Article in journal (Refereed)
    Abstract [en]

    Background: Detection of active tuberculosis (TB) before antiretroviral therapy (ART) initiation is important, but optimal diagnostic methods for use in resource-limited settings are lacking. We assessed the prevalence of TB, evaluated the diagnostic yield of Xpert MTB/RIF in comparison with smear microscopy and culture, and the impact of Xpert results on clinical management in HIV-positive adults eligible for ART at health centers in a region of Ethiopia. Methods: Participants were prospectively recruited and followed up at 5 health centers. Trained nurses collected data on socio-demographic characteristics, medical history and symptoms, and performed physical examination. Two paired morning sputum samples were obtained, and lymph node aspirates in case of lymphadenopathy. Diagnostic yield of Xpert MTB/RIF in sputum was compared with smear microscopy and liquid culture. Results: TB was diagnosed in 145/812 participants (17.9%), with bacteriological confirmation in 137 (16.9%). Among bacteriologically confirmed cases, 31 were smear-positive (22.6%), 96 were Xpert-positive (70.1%), and 123 were culture-positive (89.8%). Xpert MTB/RIF increased the TB detection rate by 64 cases (47.4%) compared with smear microscopy. The overall sensitivity of Xpert MTB/RIF was 66.4%, and was not significantly lower when testing one compared with two samples. While Xpert MTB/RIF was 46.7% sensitive among patients with CD4 cell counts greater than200 cells/mm(3), this increased to 82.9% in those with CD4 cell counts less than= 100 cells/mm(3). Compared with Xpert-positive TB patients, Xpert-negative cases had less advanced HIV and TB disease characteristics. Conclusions: Previously undiagnosed TB is common among HIV-positive individuals managed in Ethiopian health centers. Xpert MTB/RIF increased TB case detection, especially in patients with advanced immunosuppression. An algorithm based on the use of a single morning sputum sample for individuals with negative sputum smear microscopy could be considered for intensified case finding in patients eligible for ART. However, technical and cost-effectiveness issues relevant for low-income countries warrant further study.

  • 10.
    Balcha, Taye T.
    et al.
    Lund University, Sweden Minist Heatlh, Ethiopia .
    Winqvist, Niclas
    Lund University, Sweden Regional Department Infect Disease Control and Prevent, Sweden .
    Sturegard, Erik
    Clin Microbiol Regional and University of Labs, Sweden .
    Skogmar, Sten
    Lund University, Sweden .
    Reepalu, Anton
    Lund University, Sweden .
    Jemal, Zelalem H.
    Oromia Regional Health Bur, Ethiopia .
    Tibesso, Gudeta
    Columbia University, Ethiopia .
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Department of Clinical Microbiology and Infectious Diseases, Kalmar County Hospital, Kalmar, Sweden.
    Bjorkman, Per
    Lund University, Sweden .
    Detection of lipoarabinomannan in urine for identification of active tuberculosis among HIV-positive adults in Ethiopian health centres2014In: Tropical medicine & international health, ISSN 1360-2276, E-ISSN 1365-3156, Vol. 19, no 6, p. 734-742Article in journal (Refereed)
    Abstract [en]

    ObjectiveTo assess the diagnostic performance of urine lipoarabinomannan (LAM) detection for TB screening in HIV-positive adults in Ethiopia. MethodsTesting for LAM was performed using the Determine TB-LAM lateral flow assay on urine samples from participants in a prospective cohort with baseline bacteriological categorisation for active TB in sputum. Characteristics of TB patients with regard to LAM status were determined. Participants were followed for 6months to evaluate survival, retention in care and incident TB. ResultsPositive LAM results were found in 78/757 participants. Among 128 subjects with definite (confirmed by culture and/or Xpert MTB/RIF) TB, 33 were LAM-positive (25.8%); the respective figure for clinically diagnosed cases was 2/20 (10%). Five of the remaining 43 LAM-positive individuals had died during the 6-month follow-up period, whereas 38 remained in care without clinical signs of TB. The overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were 25.8%, 92.9%, 42.3% and 86.0%, respectively. Among TB patients, LAM positivity was associated with higher WHO clinical stage, lower body mass index (BMI), CD4 cell and haemoglobin levels, and with increased mortality. A combination algorithm of urine LAM testing and sputum smear microscopy detected 49 (38.2%) of definite TB cases; among those with CD4 count 100cells/mm(3), this proportion was 66.7%. ConclusionsThe performance of urine LAM testing for TB detection was poor in this population. However, this was improved among subjects with CD4 count 100cells/mm(3). In combination with sputum microscopy urine, LAM could be considered for targeted TB screening in this subgroup.

  • 11.
    Barbe, Laure
    et al.
    Univ Nantes, France.
    Le Moullac-Vaidye, Beatrice
    Univ Nantes, France.
    Echasserieau, Klara
    Univ Nantes, France; Univ Nantes, France.
    Bernardeau, Karine
    Univ Nantes, France; Univ Nantes, France.
    Carton, Thomas
    Biofortis, France.
    Bovin, Nicolai
    RAS, Russia.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Inst, Sweden.
    Ruvoen-Clouet, Nathalie
    Univ Nantes, France; Oniris, France.
    Le Pendu, Jacques
    Univ Nantes, France.
    Histo-blood group antigen-binding specificities of human rotaviruses are associated with gastroenteritis but not with in vitro infection2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, article id 12961Article in journal (Refereed)
    Abstract [en]

    Human strains of rotavirus A (RVAs) recognize fucosylated glycans belonging to histo-blood group antigens (HBGAs) through their spike protein VP8*. Lack of these ligands due to genetic polymorphisms is associated with resistance to gastroenteritis caused by P[8] genotype RVAs. With the aim to delineate the contribution of HBGAs in the process, we analyzed the glycan specificity of VP8* proteins from various P genotypes. Binding to saliva of VP8* from P[8] and P[4] genotypes required expression of both FUT2 and FUT3 enzymes, whilst binding of VP8* from the P[14] genotype required FUT2 and A enzymes. We further defined a glycan motif, GlcNAc beta 3Gal beta 4GlcNAc, recognized by P[6] clinical strains. Conversion into Lewis antigens by the FUT3 enzyme impaired recognition, explaining their lower binding to saliva of Lewis positive phenotype. In addition, the presence of neutralizing antibodies was associated with the presence of the FUT2 wild type allele in sera from young healthy adults. Nonetheless, in vitro infection of transformed cell lines was independent of HBGAs expression, indicating that HBGAs are not human RV receptors. The match between results from saliva-based binding assays and the epidemiological data indicates that the polymorphism of human HBGAs controls susceptibility to RVAs, although the exact mechanism remains unclear.

  • 12.
    Bengtsson, Torbjörn
    et al.
    Örebro University, Sweden.
    Zhang, Boxi
    Karolinska Institutet, Sweden.
    Selegård, Robert
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering. Örebro University, Sweden.
    Wiman, Emanuel
    Örebro University, Sweden.
    Aili, Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Khalaf, Hazem
    Örebro University, Sweden.
    Dual action of bacteriocin PLNC8 alpha beta through inhibition of Porphyromonas gingivalis infection and promotion of cell proliferation2017In: Pathogens and Disease, E-ISSN 2049-632X, Vol. 75, no 5, article id ftx064Article in journal (Refereed)
    Abstract [en]

    Periodontitis is a chronic inflammatory disease that is characterised by accumulation of pathogenic bacteria, including Porphyromonas gingivalis, in periodontal pockets. The lack of effective treatments has emphasised in an intense search for alternative methods to prevent bacterial colonisation and disease progression. Bacteriocins are bacterially produced antimicrobial peptides gaining increased consideration as alternatives to traditional antibiotics. We show rapid permeabilisation and aggregation of P. gingivalis by the two-peptide bacteriocin PLNC8 alpha beta. In a cell culture model, P. gingivalis was cytotoxic against gingival fibroblasts. The proteome profile of fibroblasts is severely affected by P. gingivalis, including induction of the ubiquitin-proteasome pathway. PLNC8 alpha beta enhanced the expression of growth factors and promoted cell proliferation, and suppressed proteins associated with apoptosis. PLNC8 alpha beta efficiently counteracted P. gingivalis-mediated cytotoxicity, increased expression of a large number of proteins and restored the levels of inflammatory mediators. In conclusion, we show that bacteriocin PLNC8 alpha beta displays dual effects by acting as a potent antimicrobial agent killing P. gingivalis and as a stimulatory factor promoting cell proliferation. We suggest preventive and therapeutical applications of PLNC8 alpha beta in periodontitis to supplement the host immune defence against P. gingivalis infection and support wound healing processes.

  • 13.
    Berglund, Björn
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Chen, Baoli
    Shandong Ctr Dis Control and Prevent, Peoples R China.
    Tärnberg, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Sun, Qiang
    Shandong Univ, Peoples R China.
    Xu, Liuchen
    Shandong Ctr Dis Control and Prevent, Peoples R China.
    Welander, Jenny
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Microbiology.
    Li, Yan
    Shandong Ctr Dis Control and Prevent, Peoples R China.
    Bi, Zhenwang
    Shandong Ctr Dis Control and Prevent, Peoples R China.
    Nilsson, Maud
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nilsson, Lennart E
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Characterization of extended-spectrum -lactamase-producing Escherichia coli harboring mcr-1 and toxin genes from human fecal samples from China2018In: FUTURE COMPUTING ... the ... International Conference on Future Computational Technologies and Applications, ISSN 1746-0913, E-ISSN 1999-5903, Vol. 13, no 15, p. 1647-1656Article in journal (Refereed)
    Abstract [en]

    Aim: To characterize extended-spectrum -lactamase-producing Escherichia coli harboring the colistin resistance gene mcr-1 from human fecal samples collected in 2012 in a rural area of Shandong province, PR China. Materials amp; methods: Whole-genome sequencing and antimicrobial susceptibility testing was performed on 25 mcr-1-positive isolates to determine carriage of antibiotic resistance and virulence genes, diversity and antibiotic resistance profiles. Results: The isolates were highly genetically diverse and carried a large variety of different antibiotic resistance genes. The multidrug-resistance rate was high (96%). Virulence genes associated with intestinal pathogenic E. coli were carried by 32% of the isolates. Conclusion: Further monitoring of the epidemiological situation is necessary to ensure a preparedness for potential emergence of novel, difficult-to-treat strains and awareness of available treatment options.

  • 14.
    Bi, Zhenwang
    et al.
    Shandong Centre Disease Control and Prevent, Peoples R China.
    Berglund, Björn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Sun, Qiang
    Shandong University, Peoples R China; Shandong University, Peoples R China.
    Nilsson, Maud
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Chen, Baoli
    Shandong Centre Disease Control and Prevent, Peoples R China.
    Tärnberg, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Ding, Lilu
    Shandong University, Peoples R China.
    Stalsby Lundborg, Cecilia
    Karolinska Institute, Sweden.
    Bi, Zhenqiang
    Shandong Centre Disease Control and Prevent, Peoples R China.
    Tomson, Goran
    Karolinska Institute, Sweden.
    Yao, Jingjing
    Shandong University, Peoples R China.
    Gu, Zhanying
    Shandong University, Peoples R China.
    Yin, Xiao
    Jinan Central Hospital, Peoples R China.
    Kou, Zengqiang
    Shandong Centre Disease Control and Prevent, Peoples R China.
    Nilsson, Lennart E
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Prevalence of the mcr-1 colistin resistance gene in extended-spectrum beta-lactamase-producing Escherichia coli from human faecal samples collected in 2012 in rural villages in Shandong Province, China2017In: International Journal of Antimicrobial Agents, ISSN 0924-8579, E-ISSN 1872-7913, Vol. 49, no 4, p. 493-497Article in journal (Refereed)
    Abstract [en]

    Since its initial discovery in China in 2015, the plasmid-mediated colistin resistance gene mcr-1 has been reported in Escherichia coli isolated from clinical samples, animals and meat worldwide. In this study, 706 extended-spectrum beta-lactamase (ESBL)-producing E. coli from 411 persons were detected in a collection of faecal samples from 1000 rural residents in three counties in Shandong Province, China. These isolates were screened for mcr-1 and phenotypic colistin resistance. The gene was found in 3.5% of the isolates (from 4.9% of persons) from all three counties. All isolates with phenotypic colistin resistance carried mcr-1. These data indicate that commensal carriage of ESBL-producing E. coli with mcr-1 among persons in rural China was already present in 2012 and that mcr-1 was the most important colistin resistance mechanism. Interventions are necessary to minimise further dissemination of mcr-1, which would limit the future usefulness of colistin as a last-resort antibiotic. (C) 2017 Elsevier B.V. and International Society of Chemotherapy. All rights reserved.

  • 15.
    Blomberg, Jonas
    et al.
    Uppsala Univ, Sweden.
    Rizwan, Muhammad
    Uppsala Univ, Sweden.
    Bohlin-Wiener, Agnes
    Uppsala Univ, Sweden; Karolinska Inst, Sweden.
    Elfaitouri, Amal
    Benghazi Univ, Libya.
    Julin, Per
    Stora Skondal, Sweden; Karolinska Inst, Sweden.
    Zachrisson, Olof
    Gottfries Clin AB, Sweden.
    Rosén, Anders
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Gottfries, Carl-Gerhard
    Gottfries Clin AB, Sweden.
    Antibodies to Human Herpesviruses in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Patients2019In: Frontiers in Immunology, ISSN 1664-3224, E-ISSN 1664-3224, Vol. 10, article id 1946Article in journal (Refereed)
    Abstract [en]

    Myalgic encephalomyelitis, also referred to as chronic fatigue syndrome (ME/CFS) is a debilitating disease characterized by myalgia and a sometimes severe limitation of physical activity and cognition. It is exacerbated by physical and mental activity. Its cause is unknown, but frequently starts with an infection. The eliciting infection (commonly infectious mononucleosis or an upper respiratory infection) can be more or less well diagnosed. Among the human herpesviruses (HHV-1 -8), HHV-4 (Epstein-Barr virus; EBV), HHV-6 (including HHV-6A and HHV-6B), and HHV-7, have been implicated in the pathogenesis of ME/CFS. It was therefore logical to search for serological evidence of past herpesvirus infection/reactivation in several cohorts of ME/CFS patients (all diagnosed using the Canada criteria). Control samples were from Swedish blood donors. We used whole purified virus, recombinant proteins, and synthetic peptides as antigens in a suspension multiplex immunoassay (SMIA) for immunoglobulin G (IgG). The study on herpesviral peptides based on antigenicity with human sera yielded novel epitope information. Overall, IgG anti-herpes-viral reactivities of ME/CFS patients and controls did not show significant differences. However, the high precision and internally controlled format allowed us to observe minor relative differences between antibody reactivities of some herpesviral antigens in ME/CFS versus controls. ME/CFS samples reacted somewhat differently from controls with whole virus HHV-1 antigens and recombinant EBV EBNA6 and EA antigens. We conclude that ME/CFS samples had similar levels of IgG reactivity as blood donor samples with HHV-1-7 antigens. The subtle serological differences should not be over-interpreted, but they may indicate that the immune system of some ME/CFS patients interact with the ubiquitous herpesviruses in a way different from that of healthy controls.

  • 16.
    Blomgran, Robert
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Microbe-induced apoptosis in phagocytic cells and its role in innate immunity2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Apoptosis, or programmed cell death, is a controlled process by which aged or damages cells are eliminated in multicellular organisms. Neutrophils, short-lived phagocytes of the innate immune system, are highly equipped effectors that can sense, locate, ingest and kill bacterial pathogens. Inflammatory mediators and the presence of bacterial products at the foci of infection regulate the function and life span of these cells. Modulation of neutrophil apoptosis and the subsequent clearance by scavenger cells, such as macrophages, is part of a balanced inflammatory process leading to resolution of inflammation. Many pathogens are capable of modulating host cell apoptosis, and thereby influence the progression of disease. Hence, this thesis was aiming at elucidating mechanisms involved in pathogen- and host-modulated apoptosis and its contribution to the inflammatory process.

    We found that different routes of bacterial entry, i.e. through invasion or by receptor-mediated phagocytosis, triggered different signaling pathways within phagocytes. Invasion of virulent Salmonella caused apoptosis, a process requiring activation of the Rho GTPases Rac1 and Cdc42. On the other hand, phagocytosis of the non-invasive Salmonella inhibited apoptosis despite similar intracellular survival as the invasive bacteria. Protection against phagocytosis-induced apoptosis was regulated by tyrosine- and PI3-kinase-dependent activation of AKT (also called PKB for protein kinase B). Furthermore, inhibiting the intraphagosomal production of reactive oxygen species (ROS) in neutrophils during phagocytosis of E. coli decreased apoptosis below spontaneous apoptosis, further indicating that both pro- and anti-apoptotic pathways are triggered by receptor-mediated phagocytosis.

    Type 1 fimbria-expressing E. coli adhering to neutrophils resisted ingestion, and induced a ROS-dependent apoptosis by a cooperative effect of the FimH adhesin and LPS. To explore how compartmentalization of ROS during neutrophil activation was involved in modulating apoptosis, we evaluated the stability of lysosomes. In contrast to phagocytosis of E. coli, the adhesive strain induced intracellular non-phagosomal ROS production which triggered early permeabilization and release of lysosomal enzymes to the cytosol. Cathepsin B and/or L were responsible for targeting of the pro-apoptotic Bcl-2 protein Bid, thereby inducing mitochondrial damage, and apoptosis. These data propose a novel pathway for ROS-induced apoptosis in human neutrophils, where the location of the ROS rather than production per se is important.

    Moreover, we found that pathogen-induced apoptotic neutrophils, in contrast to uninfected apoptotic neutrophils, activated blood-monocyte derived macrophages to increase their FcγRI surface expression and to produce large quantities of the pro-inflammatory cytokine TNF-α. This demonstrates that during the early phase of infection, pathogen-induced neutrophil apoptosis will help local macrophages to gain control over the microbes. Furthermore, we suggest that heat shock protein 60 and 70 represent a stress signal that enables macrophages to distinguish between, and react differently to, uninfected and inflammatory apoptotic neutrophils.

    List of papers
    1. Differential effects of invasion by and phagocytosis of Salmonella typhimurium on apoptosis in human macrophages: potential role of Rho–GTPases and Akt
    Open this publication in new window or tab >>Differential effects of invasion by and phagocytosis of Salmonella typhimurium on apoptosis in human macrophages: potential role of Rho–GTPases and Akt
    Show others...
    2003 (English)In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 74, no 4, p. 620-629Article in journal (Refereed) Published
    Abstract [en]

    In addition to direct activation of caspase-1 and induction of apoptosis by SipB, invasive Salmonella stimulates multiple signaling pathways that are key regulators of host cell survival. Nevertheless, little is known about the relative contributions of these pathways to Salmonella-mediated death of macrophages. We studied human monocytic U937 cells and found that apoptosis was induced by invading wild-type Salmonella typhimurium but not by phagocytosed, serum-opsonized, noninvasive Salmonella mutants. Pretreating U937 cells with inhibitors of tyrosine kinases or phosphatidylinositol-3 kinase (PI-3K) completely blocked phagocytosis of opsonized Salmonella mutants but did not affect invasion by wild-type Salmonella or the apoptosis caused by invasion. However, pretreatment with GGTI-298, a geranylgeranyltransferase-1 inhibitor that prevents prenylation of Cdc42 and Rac1, suppressed Salmonella-induced apoptosis by ∼70%. Transduction of Tat fusion constructs containing dominant-negative Cdc42 or Rac1 significantly inhibited Salmonella-induced cell death, indicating that the cytotoxicity of Salmonella requires activation of Cdc42 and Rac. In contrast to phagocytosis of opsonized bacteria, invasion by S. typhimurium stimulated Cdc42 and Rac1, regardless of the activities of tyrosine- or PI-3K. Moreover, Salmonella infection activated Akt protein in a tyrosine-kinase or PI-3K-dependent manner, and a reduced expression of Akt by antisense transfection rendered the cells more sensitive to apoptosis induced by opsonized Salmonella. These results indicate that direct activation of Cdc42 and Rac1 by invasive Salmonella is a prerequisite of Salmonella-mediated death of U937 cells, whereas the simultaneous activation of Akt by tyrosine kinase and PI-3K during receptor-mediated phagocytosis protects cells from apoptosis.

    Keywords
    macrophages, bacterial apoptosis, signal transduction
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14003 (URN)10.1189/jlb.1202586 (DOI)
    Available from: 2006-09-27 Created: 2006-09-27 Last updated: 2017-12-13Bibliographically approved
    2. Uropathogenic Escherichia coli triggers oxygen-dependent apoptosis in human neutrophils through the cooperative effect of type 1 fimbriae and lipopolysaccharide
    Open this publication in new window or tab >>Uropathogenic Escherichia coli triggers oxygen-dependent apoptosis in human neutrophils through the cooperative effect of type 1 fimbriae and lipopolysaccharide
    2004 (English)In: Infection and Immunity, ISSN 0019-9567, Vol. 72, no 8, p. 4570-4578Article in journal (Refereed) Published
    Abstract [en]

    Type 1 fimbriae are the most commonly expressed virulence factor on uropathogenic Escherichia coli. In addition to promoting avid bacterial adherence to the uroepithelium and enabling colonization, type 1 fimbriae recruit neutrophils to the urinary tract as an early inflammatory response. Using clinical isolates of type 1 fimbriated E. coli and an isogenic type 1 fimbria-negative mutant (CN1016) lacking the FimH adhesin, we investigated if these strains could modulate apoptosis in human neutrophils. We found that E. coli expressing type 1 fimbriae interacted with neutrophils in a mannose- and lipopolysaccharide (LPS)-dependent manner, leading to apoptosis which was triggered by the intracellular generation of reactive oxygen species. This induced neutrophil apoptosis was abolished by blocking FimH-mediated attachment, by inhibiting NADPH oxidase activation, or by neutralizing LPS. In contrast, CN1016, which did not adhere to or activate the respiratory burst of neutrophils, delayed the spontaneous apoptosis in an LPS-dependent manner. This delayed apoptosis could be mimicked by adding purified LPS and was also observed by using fimbriated bacteria in the presence of D-mannose. These results suggest that LPS is required for E. coli to exert both pro- and antiapoptotic effects on neutrophils and that the difference in LPS presentation (i.e., with or without fimbriae) determines the outcome. The present study showed that there is a fine-tuned balance between type 1 fimbria-induced and LPS-mediated delay of apoptosis in human neutrophils, in which altered fimbrial expression on uropathogenic E. coli determines the neutrophil survival and the subsequent inflammation during urinary tract infections.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14004 (URN)10.1128/IAI.72.8.4570-4578.2004 (DOI)
    Available from: 2006-09-27 Created: 2006-09-27 Last updated: 2009-04-28
    3. Cathepsin-cleaved Bid promotes apoptosis in human neutrophils via oxidative stress-induced lysosomal membrane permeabilization
    Open this publication in new window or tab >>Cathepsin-cleaved Bid promotes apoptosis in human neutrophils via oxidative stress-induced lysosomal membrane permeabilization
    2007 (English)In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 81, p. 1213-1223Article in journal (Refereed) Published
    Abstract [en]

    Lysosomal membrane permeabilization (LMP) is emerging as an important regulator of cell apoptosis. Human neutrophils are highly granulated phagocytes, which respond to pathogens by exhibiting increased production of reactive oxygen species (ROS) and lysosomal degranulation. In a previous study, we observed that intracellular, nonphagosomal generation of ROS triggered by adherent bacteria induced ROS-dependent neutrophil apoptosis, whereas intraphagosomal production of ROS during phagocytosis had no effect. In the present study, we measured lysosomal membrane stability and leakage in human neutrophils and found that adherent, noningested, Type 1-fimbriated Escherichia coli bacteria induced LMP rapidly in neutrophils. Pretreatment with the NADPH oxidase inhibitor diphenylene iodonium markedly blocked the early LMP and apoptosis in neutrophils stimulated with Type 1-fimbriated bacteria but had no effect on the late LMP seen in spontaneously apoptotic neutrophils. The induced lysosomal destabilization triggered cleavage of the proapoptotic Bcl-2 protein Bid, followed by a decrease in the antiapoptotic protein Mcl-1. Involvement of LMP in initiation of apoptosis is supported by the following observations: Bid cleavage and the concomitant drop in mitochondrial membrane potential required activation of cysteine-cathepsins but not caspases, and the differential effects of inhibitors of cysteine-cathepsins and cathepsin D on apoptosis coincided with their ability to inhibit Bid cleavage in activated neutrophils. Together, these results indicate that in microbe-induced apoptosis in neutrophils, ROS-dependent LMP represents an early event in initiation of the intrinsic apoptotic pathway, which is followed by Bid cleavage, mitochondrial damage, and caspase activation.

    Keywords
    bacteria, Bcl-2 family proteins, Escherichia coli, lysosomes, Mcl-1, reactive oxygen species
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14005 (URN)doi:10.1189/jlb.0506359 (DOI)
    Available from: 2006-09-27 Created: 2006-09-27 Last updated: 2017-12-13
    4. Pathogen-Induced Apoptotic Neutrophils Express Heat Shock Proteins and Elicit Activation of Human Macrophages
    Open this publication in new window or tab >>Pathogen-Induced Apoptotic Neutrophils Express Heat Shock Proteins and Elicit Activation of Human Macrophages
    Show others...
    2004 (English)In: Journal of immunology, ISSN 0022-1767, Vol. 173, no 10, p. 6319-6326Article in journal (Refereed) Published
    Abstract [en]

    Ingestion of aged or irradiated apoptotic neutrophils actively suppresses stimulation of macrophages (MΦ). Many bacterial pathogens can also provoke apoptosis in neutrophils, but little is known about how such apoptotic cells influence MΦ activation. We found that neutrophils undergoing apoptosis induced by UV irradiation, Escherichia coli, or Staphylococcus aureus could either stimulate or inhibit MΦ activation. In contrast to MΦ that had ingested irradiated apoptotic neutrophils, MΦ that had phagocytosed bacteria-induced apoptotic neutrophils exhibited markedly increased production of the proinflammatory cytokine TNF-α, but not the anti-inflammatory cytokine TGF-β. Moreover, ingestion of bacteria, but not UV-induced apoptotic neutrophils, caused increased expression of FcγRI on MΦ, and this effect was not provoked directly by bacteria associated with the apoptotic neutrophils. Instead, we found that a link between pathogen-induced apoptotic neutrophils and up-regulation of the heat shock proteins HSP60 and HSP70, and we also observed that recombinant HSP60 and HSP70 potentiated LPS-stimulated production of TNF-α in MΦ. The opposing macrophage responses to neutrophils undergoing apoptosis induced in different ways may represent a novel mechanism that regulates the extent of the immune response to invading microbes in two steps: first by aiding the functions of MΦ at an early stage of infection, and subsequently by deactivating those cells through removal of uninfected apoptotic neutrophils. HSP induction in neutrophils may provide the danger signals required to generate a more effective macrophage response.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14006 (URN)
    Available from: 2006-09-27 Created: 2006-09-27 Last updated: 2009-06-09
  • 17.
    Bucardo, F.
    et al.
    Department of Microbiology, University of León (UNAN-León), León, Nicaragua.
    Mercado, J.
    National Center for Diagnostic and Reference, Ministry of Health, Managua, Nicaragua.
    Reyes, Y.
    Department of Microbiology, University of León (UNAN-León), León, Nicaragua.
    González, F.
    Department of Microbiology, University of León (UNAN-León), León, Nicaragua.
    Balmaseda, A
    National Center for Diagnostic and Reference, Ministry of Health, Managua, Nicaragua.
    Nordgren, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Medicine and Health Sciences.
    Large increase of rotavirus diarrhoea in the hospital setting associated with emergence of G12 genotype in a highly vaccinated population in Nicaragua.2015In: Clinical Microbiology and Infection, ISSN 1198-743X, E-ISSN 1469-0691, Vol. 21, no 6, p. 603.e1-603.e7Article in journal (Refereed)
    Abstract [en]

    Rotaviruses (RVs) are a major cause of severe diarrhoea in young children. Nicaragua introduced routine immunization with the pentavalent RV vaccine (RV5) in 2006, which greatly reduced the incidence of diarrhoea. A remaining concern has been the possible emergence of new RV strains to which the vaccination has less effect. In this study, 837 children with diarrhoea in hospital settings were investigated for RV between May 2011 and July 2013. RVs were subsequently typed by multiplex PCR and/or sequencing. Fecal anti-RV IgA titres for a subset of RV-infected (n = 137) and noninfected children (n = 52) were determined with an in-house enzyme-linked immunosorbent assay. The RV detection rate was 8% in 2011, followed by a sharp increase to 29% in 2012 and 19% in 2013. This was associated with emergence and predominance of genotype G12 RV, from 0% in 2011 to 66% in 2012 and 82% in 2013, infecting children from 1 month to 10 years of age. Two sequenced G12 strains showed a Wa-like genome with genotype G12-P[8]-I1-R1-C1-M1-A1-N1-T1-E1-H1, similar to the globally emerging G12 strains. Fecal anti-RV IgA analysis showed that most G12-infected and noninfected children had been in contact with either vaccine or wild RV strains, but such antibodies did not prevent symptomatic G12 infection. A marked increase of RV was evident in the hospital setting associated with a nationwide emergence and predominance of RV G12 genotype in a population with high RV5 vaccine coverage.

  • 18.
    Bucardo, Filemon
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Kindberg, Elin
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Paniagua, Margarita
    Department of Microbiology, University of León, Nicaragua.
    Vildevall, Malin
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Genetic susceptibility to symptomatic norovirus infection in Nicaragua2009In: Journal of Medical Virology, ISSN 0146-6615, E-ISSN 1096-9071, Vol. 81, no 4, p. 728-735Article in journal (Refereed)
    Abstract [en]

    Host genetic resistance to Norovirus (NoV) has been observed in challenge and outbreak studies in populations from Europe, Asia, and USA. In this study, we have investigated if histo-blood group antigens can predict susceptibility to diarrhea caused by NoV in Nicaragua, Central America, and if this can be reflected in antibody-prevalence and titer to NoV among individuals with different histo-blood group antigen phenotypes. Investigation of 28 individuals infected with NoV and 131 population controls revealed 6% of non-secretors in the population and nil non-secretors among patients infected with NoV, suggesting that non-secretors may be protected against NoV disease in Nicaragua. Surprisingly, 25% of the population was Lewis negative (Le(a-b-)). NoV infections with genogroup I (GI) and GII occurred irrespective of Lewis genotype, but none of the Lewis a positive (Le(a + b-)) were infected. The globally dominating GII.4 virus infected individuals of all blood groups except AB (n = 5), while the GI viruses (n = 4) infected only blood type O individuals. Furthermore, O blood types were susceptible to infections with GI.4, GII.4, GII.7, GII.17, and GII.18-Nica viruses, suggesting that secretors with blood type O are susceptible (OR = 1.52) and non-secretors resistant. The overall antibody-prevalence to NoV GII.3 VLP was 62% with the highest prevalence among blood type B carriers (70%) followed by A (68%) and O (62%). All four investigated individuals carrying blood type AB were antibody-negative. Among secretors, 63% were antibody-positive compared to 33% among non-secretors (P = 0.151). This study extends previous knowledge about the histo-blood group antigens role in NoV disease in a population with different genetic background than North American and European.

  • 19.
    Chenna Narendra, Sudeep
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Systemic and local regulation of experimental arthritis by IFN-α, dendritic cells and uridine2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, we have studied the immunological processes of joint inflammation that may be targets for future treatment of patients with arthritis. We focus on the immune-modulating properties of interferon-α (IFN-α) and uridine in experimental arthritis. The nucleoside uridine, which is regarded a safe treatment has anti-inflammatory properties notably by inhibiting tumor necrosis factor (TNF) release. Because the inflamed synovium in rheumatoid arthritis (RA) is characterised by pathogenic TNF-production, uridine could potentially be away to ameliorate arthritis. Systemic administration of uridine had no effect on antigeninduced arthritis (AIA), which is a T-cell dependent model where animals are immunized twice (sensitization) with bovine serum albumin (mBSA), before local triggering of arthritis by intra-articular antigen (mBSA) re-challenge. In contrast, intra-articular administration of uridine clearly down modulated development of AIA in a dose dependent manner and inhibited the expression of synovial adhesion molecules, influx of inflammatory leukocytes and synovial expression of TNF and interleukin 6, but did not affect systemic levels of proinflammatory cytokines or antigen-specific T-cell responses. Local administration of uridine may thus be a viable therapeutic option for treatment of arthritis in the future.

    Viral double-stranded deoxyribonucleic acid (dsRNA), a common nucleic acid found in most viruses, can be found in the joints of RA patients and local deposition of such viral dsRNA induces arthritis by activating IFN-α. Here we show that arthritis induced by dsRNA can be mediated by IFN-producing dendritic cells in the joint and this may thus explain why viral infections are sometimes associated with arthritis.

    Earlier, to study the effect of dsRNA and IFN-α in an arthritis model, that like RA, is dependent on adaptive immunity, dsRNA and IFN-α were administered individually during the development of AIA. Both molecules clearly protected against AIA in a type I IFN receptor-dependent manner but were only effective if administered in the sensitization phase of AIA. Here we show that the anti-inflammatory effect of IFN-α is critically dependent on signalling via transforming growth factor β (TGF-β) and the enzymatic activity of indoleamine 2,3 dioxygenase 1 (IDO). The IDO enzyme is produced by plasmacytoid DC and this cell type was critically required both during antigen sensitization and in the arthritis phase of AIA for the protective effect of IFN-α against AIA. In contrast, TGF-β and the enzymatic activity of IDO were only required during sensitization, which indicate that they are involved in initial steps of tolerogenic antigen sensitization. In this scenario, IFN- α first activates the enzymatic activity of IDO in pDC, which converts Tryptophan to Kynurenine, which thereafter activates TGF-β. Common for IDO-expressing pDC, Kyn and TGF-β is their ability to induce development of regulatory T cells (Tregs). We found that Tregs were crucial for IFN-α-mediated protection against AIA, but only in the arthritis phase. In line with this, adoptive transfer of Tregs isolated from IFN-α treated mice to recipient animals in the arthritis phase clearly protected against AIA. The numbers of Tregs were not significantly altered by IFN-α but IFN-α increased the suppressive capacity of Tregs against antigen-induced proliferation. This enhanced suppressive activity of Tregs in the arthritis phase was dependent on the earlier activated enzyme IDO1 during the sensitization phase of AIA. Thus, presence of IFN-α at the time of antigen sensitization activates the enzymatic activity of IDO, which generates Tregs with enhanced suppressive capacity that upon antigen re-challenge prevents inflammation. We have thus identified one example of how immune tolerance can be developed, that may be a future way to combat autoimmunity.

    List of papers
    1. Local but Not Systemic Administration of Uridine Prevents Development of Antigen-Induced Arthritis
    Open this publication in new window or tab >>Local but Not Systemic Administration of Uridine Prevents Development of Antigen-Induced Arthritis
    2015 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, no 10, p. e0141863-Article in journal (Refereed) Published
    Abstract [en]

    Objective Uridine has earlier been show to down modulate inflammation in models of lung inflammation. The aim of this study was to evaluate the anti-inflammatory effect of uridine in arthritis. Methods Arthritis was induced by intra-articular injection of mBSA in the knee of NMRI mice preimmunized with mBSA. Uridine was either administered locally by direct injection into the knee joint or systemically. Systemic treatment included repeated injections or implantation of a pellet continuously releasing uridine during the entire experimental procedure. Anti-mBSA specific immune responses were determined by ELISA and cell proliferation and serum cytokine levels were determined by Luminex. Immunohistochemistry was used to identify cells, study expression of cytokines and adhesion molecules in the joint. Results Local administration of 25-100 mg/kg uridine at the time of arthritis onset clearly prevented development of joint inflammation. In contrast, systemic administration of uridine (max 1.5 mg uridine per day) did not prevent development of arthritis. Protection against arthritis by local administration of uridine did not affect the anti-mBSA specific immune response and did not prevent the rise in serum levels of pro-inflammatory cytokines associated with the triggering of arthritis. In contrast, local uridine treatment efficiently inhibited synovial expression of ICAM-1 and CD18, local cytokine production and recruitment of leukocytes to the synovium. Conclusion Local, but not systemic administration of uridine efficiently prevented development of antigen- induced arthritis. The protective effect did not involve alteration of systemic immunity to mBSA but clearly involved inhibition of synovial expression of adhesion molecules, decreased TNF and IL-6 production and prevention of leukocyte extravasation. Further, uridine is a small, inexpensive molecule and may thus be a new therapeutic option to treat joint inflammation in RA.

    Place, publisher, year, edition, pages
    PUBLIC LIBRARY SCIENCE, 2015
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-123070 (URN)10.1371/journal.pone.0141863 (DOI)000363920300089 ()26512984 (PubMedID)
    Note

    Funding Agencies|Vetenskapsradet-Grant [521-2011-3095]; Reumatikerforbundet Grant [155261]; County Council of Ostergotland, Sweden; Linkoping University

    Available from: 2015-12-04 Created: 2015-12-03 Last updated: 2017-12-01
    2. IDO1 and TGF-beta Mediate Protective Effects of IFN-alpha in Antigen-Induced Arthritis
    Open this publication in new window or tab >>IDO1 and TGF-beta Mediate Protective Effects of IFN-alpha in Antigen-Induced Arthritis
    Show others...
    2016 (English)In: Journal of Immunology, ISSN 0022-1767, E-ISSN 1550-6606, Vol. 197, no 8, p. 3142-3151Article in journal (Refereed) Published
    Abstract [en]

    IFN-alpha prevents Ag-induced arthritis (AIA), and in this study we investigated the role of IDO1 and TGF-beta signaling for this anti-inflammatory property of IFN-alpha. Arthritis was induced by methylated BSA (mBSA) in mBSA-sensitized wild-type (WT), Ido1(-/-), or Ifnar(-/-) mice, treated or not with IFN-alpha or the IDO1 product kynurenine (Kyn). Enzymatic IDO1 activity, TGF-beta, and plasmacytoid dendritic cells (pDC) were neutralized by 1-methyltryptophan and Abs against TGF-beta and pDC, respectively. IDO1 expression was determined by RT-PCR, Western blot, and FACS, and enzymatic activity by HPLC. Proliferation was measured by H-3-thymidine incorporation and TGF-beta by RT-PCR and ELISA. WT but not Ido1(-/-) mice were protected from AIA by IFN-alpha, and Kyn, the main IDO1 product, also prevented AIA, both in WTand Ifnar(-/-) mice. Protective treatment with IFN-alpha increased the expression of IDO1 in pDC during AIA, and Ab-mediated depletion of pDC, either during mBSA sensitization or after triggering of arthritis, completely abrogated the protective effect of IFN-alpha. IFN-alpha treatment also increased the enzymatic IDO1 activity (Kyn/tryptophan ratio), which in turn activated production of TGF-beta. Neutralization of enzymatic IDO1 activity or TGF-beta signaling blocked the protective effect of IFN-alpha against AIA, but only during sensitization and not after triggering of arthritis. Likewise, inhibition of the IDO1 enzymatic activity in the sensitization phase, but not after triggering of arthritis, subdued the IFN-alpha-induced inhibition of mBSA-induced proliferation. In conclusion, presence of IFN-alpha at Ag sensitization activates an IDO1/TGF-beta-dependent anti-inflammatory program that upon antigenic rechallenge prevents inflammation via pDC.

    Place, publisher, year, edition, pages
    AMER ASSOC IMMUNOLOGISTS, 2016
    National Category
    Immunology in the medical area
    Identifiers
    urn:nbn:se:liu:diva-133121 (URN)10.4049/jimmunol.1502125 (DOI)000387965100018 ()27647832 (PubMedID)
    Available from: 2016-12-12 Created: 2016-12-09 Last updated: 2019-02-11
    3. Dendritic cells activated by double-stranded RNA induce arthritis via autocrine type I IFN signaling.
    Open this publication in new window or tab >>Dendritic cells activated by double-stranded RNA induce arthritis via autocrine type I IFN signaling.
    2014 (English)In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 95, no 4, p. 661-666Article in journal (Refereed) Published
    Abstract [en]

    Viral dsRNA can be found at the site of inflammation in RA patients, and intra-articular injection of dsRNA induces arthritis by activating type I IFN signaling in mice. Further, DCs, a major source of IFN-α, can be found in the synovium of RA patients. We therefore determined the occurrence of DCs in dsRNA-induced arthritis and their ability to induce arthritis. Here, we show, by immunohistochemistry, that cells expressing the pan-DC marker CD11c and the pDC marker 120G8 are present in the inflamed synovium in dsRNA-induced arthritis. Flt3L-generated and splenic DCs preactivated with dsRNA before intra-articular injection, but not mock-stimulated cells, clearly induced arthritis. Induction of arthritis was dependent on type I IFN signaling in the donor DCs, whereas IFNAR expression in the recipient was not required. Sorting of the Flt3L-DC population into cDCs (CD11c(+), PDCA-1(-)) and pDCs (CD11c(+), PDCA-1(+)) revealed that both subtypes were arthritogenic and produced type I IFN if treated with dsRNA. Taken together, these results demonstrate that viral nucleic acids can elicit arthritis by activating type I IFN signaling in DCs. Once triggered, autocrine type I IFN signaling in dsRNA-activated DCs is sufficient to propagate arthritis.

    Place, publisher, year, edition, pages
    Society for Leukocyte Biology, 2014
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-102370 (URN)10.1189/jlb.0613320 (DOI)000335346300011 ()24304616 (PubMedID)
    Available from: 2013-12-09 Created: 2013-12-09 Last updated: 2017-12-06
  • 20.
    Chi, Xiaohui
    et al.
    Shandong Univ, Peoples R China.
    Berglund, Björn
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Zhejiang Univ, Peoples R China.
    Zou, Huiyun
    Shandong Univ, Peoples R China.
    Zheng, Beiwen
    Zhejiang Univ, Peoples R China.
    Börjesson, Stefan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Natl Vet Inst, Sweden.
    Ji, Xiang
    Shandong Univ, Peoples R China.
    Ottoson, Jakob
    Natl Food Agcy, Sweden.
    Lundborg, Cecilia Stalsby
    Karolinska Inst, Sweden.
    Li, Xuewen
    Shandong Univ, Peoples R China.
    Nilsson, Lennart E
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Characterization of Clinically Relevant Strains of Extended-Spectrum beta-Lactamase-Producing Klebsiella pneumoniae Occurring in Environmental Sources in a Rural Area of China by Using Whole-Genome Sequencing2019In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 10, article id 211Article in journal (Refereed)
    Abstract [en]

    Klebsiella pneumoniae is a gram-negative, opportunistic pathogen, and a common cause of healthcare-associated infections such as pneumonia, septicemia, and urinary tract infection. The purpose of this study was to survey the occurrence of and characterize K. pneumoniae in different environmental sources in a rural area of Shandong province, China. Two hundred and thirty-one samples from different environmental sources in 12 villages were screened for extended-spectrum beta-lactamase-(ESBL)-producing K. pneumoniae, and 14 (6%) samples were positive. All isolates were multidrug-resistant and a few of them belonged to clinically relevant strains which are known to cause hospital outbreaks worldwide. Serotypes, virulence genes, serum survival, and phagocytosis survival were analyzed and the results showed the presence of virulence factors associated with highly virulent clones and a high degree of phagocytosis survivability, indicating the potential virulence of these isolates. These results emphasize the need for further studies designed to elucidate the role of the environment in transmission and dissemination of ESBL-producing K. pneumoniae and the potential risk posed to human and environmental health.

  • 21.
    Crisci, Elisa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Ellegård, Rada
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Nyström, Sofia
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Immunology and Transfusion Medicine.
    Rondahl, Elin
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Center, Department of Infectious Diseases.
    Serrander, Lena
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Bergström, Tomas
    University of Gothenburg, Gothenburg, Sweden.
    Sjöwall, Christopher
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Rheumatology.
    Eriksson, Kristina
    University of Gothenburg, Gothenburg, Sweden.
    Larsson, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Complement opsonization promotes HSV-2 infection of human dendritic cells2016In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 90, no 10, p. 4939-4950Article in journal (Refereed)
    Abstract [en]

    Herpes virus type 2 (HSV2) is one of the most common sexually transmitted infections globally with a very high prevalence in many countries. During HSV2 infection viral particles become coated with complement proteins and antibodies, both existent in the genital fluids, which could influence the activation of the immune responses. In genital mucosa, the primary target cells for HSV2 infection are epithelial cells, but resident immune cells such as dendritic cells (DCs) are also infected. The DCs are the activators of the ensuing immune responses directed against HSV2, and the aim of this study was to examine the effects opsonization of HSV2, either with complement alone or with complement and antibodies, had on the infection of immature DCs and their ability to mount inflammatory and antiviral responses. Complement opsonization of HSV2 enhanced both the direct infection of immature DCs and their production of new infectious viral particles. The enhanced infection required activation of the complement cascade and functional complement receptor 3. Furthermore, HSV2 infection of DCs required endocytosis of viral particles and their delivery into an acid endosomal compartment. The presence of complement in combination with HSV1 or HSV2 specific antibodies more or less abolished the HSV2 infection of DCs.Our results clearly demonstrate the importance of studying HSV2 infection under conditions that ensue in vivo, i.e. when the virions are covered in complement fragments and complement fragments and antibodies, as this will shape the infection and the subsequent immune response and needs to be further elucidated.

    IMPORTANCE: During HSV2 infection viral particles should become coated with complement proteins and antibodies, both existent in the genital fluids, which could influence the activation of the immune responses. The dendritic cells are the activators of the immune responses directed against HSV2, and the aim of this study was to examine the effects of complement alone or complement and antibodies, on the HSV2 infection of dendritic cells and their ability to mount inflammatory and antiviral responses.Our results demonstrate that the presence of antibodies and complement in the genital environment can influence HSV2 infection under in vitro conditions that reflect the in vivo situation. We believe that our findings are highly relevant for the understanding of HSV2 pathogenesis.

  • 22.
    Dellgren, Linus
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases. inkoping, Sweden.
    Claesson, Carina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Microbiology.
    Högdahl, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Microbiology.
    Forsberg, Jon
    Not Found:Linkoping Univ, Dept Clin and Expt Med, Linkoping, Sweden; Linkoping Univ, Dept Urol, Linkoping, Sweden.
    Hanberger, Håkan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Nilsson, Lennart E
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences.
    Hällgren, Anita
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases.
    Phenotypic screening for quinolone resistance in Escherichia coli2019In: European Journal of Clinical Microbiology and Infectious Diseases, ISSN 0934-9723, E-ISSN 1435-4373, Vol. 38, no 9, p. 1765-1771Article in journal (Refereed)
    Abstract [en]

    Recent studies show that rectal colonization with low-level ciprofloxacin-resistant Escherichia coli (ciprofloxacin minimal inhibitory concentration (MIC) above the epidemiological cutoff point, but below the clinical breakpoint for resistance), i.e., in the range amp;gt; 0.06-0.5 mg/L is an independent risk factor for febrile urinary tract infection after transrectal ultrasound-guided biopsy (TRUS-B) of the prostate, adding to the other risk posed by established ciprofloxacin resistance in E. coli (MIC amp;gt; 0.5 mg/L) as currently defined. We aimed to identify the quinolone that by disk diffusion best discriminates phenotypic wild-type isolates (ciprofloxacin MIC amp;lt;= 0.06 mg/L) of E. coli from isolates with acquired resistance, and to determine the resistance genotype of each isolate. The susceptibility of 108 E. coli isolates was evaluated by ciprofloxacin, levofloxacin, moxifloxacin, nalidixic acid, and pefloxacin disk diffusion and correlated to ciprofloxacin MIC (broth microdilution) using EUCAST methodology. Genotypic resistance was identified by PCR and DNA sequencing. The specificity was 100% for all quinolone disks. Sensitivity varied substantially, as follows: ciprofloxacin 59%, levofloxacin 46%, moxifloxacin 59%, nalidixic acid 97%, and pefloxacin 97%. We suggest that in situations where low-level quinolone resistance might be of importance, such as when screening for quinolone resistance in fecal samples pre-TRUS-B, a pefloxacin (S amp;gt;= 24 mm) or nalidixic acid (S amp;gt;= 19 mm) disk, or a combination of the two, should be used. In a setting where plasmid-mediated resistance is prevalent, pefloxacin might perform better than nalidixic acid.

  • 23.
    Demirci, Mehmet
    et al.
    Department of Medical Microbiology, School of Medicine, Beykent University, Istanbul, Turkey.
    Guzel, Aylin Dag
    Department of Medical Services and Techniques, Vocational School, Istanbul Arel University, Istanbul, Turkey.
    Ersahin, Aynur Adeviye
    Department of Obstetrics and Gynecology, Medical Park Goztepe Hospital, Istanbul, Turkey.
    Yorulmaz, Eda
    Department of Biochemistry, Medical Park Bahcelievler Hospital, Istanbul, Turkey.
    Ersahin, Suat Suphan
    Department of Obstetrics and Gynecology, School of Medicine, Altinbas University, Istanbul, Turkey.
    Borsa, Baris Ata
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Surface Physics and Nano Science. Linköping University, Faculty of Science & Engineering. Department of Medical Microbiology, School of Medicine, Yeditepe University, Istanbul, Turkey.
    Human papillomavirus prevalence and genotype distribution among Turkish women with or without cervical lesion2018In: Indian Journal of Medical Microbiology, ISSN 0255-0857, E-ISSN 1998-3646, Vol. 36, no 4, p. 517-521Article in journal (Refereed)
    Abstract [en]

    Human papillomavirus (HPV) infection is the main cause of cervical cancer, but the risk is associated with the various HPV genotypes which may be found in women with or without clinical findings.

  • 24.
    Edberg, Andreas
    et al.
    Central Hospital, Karlstad.
    Jurstrand, Margaretha
    University Hospital, Örebro.
    Johansson, Eva
    Central Hospital, Karlstad.
    Wikander, Elisabeth
    Central Hospital, Karlstad.
    Höög, Anna
    Central Hospital, Karlstad.
    Ahlqvist, Thomas
    Central Hospital, Karlstad.
    Falk, Lars
    Linköping University, Department of Biomedicine and Surgery, Division of dermatology and venereology. Linköping University, Faculty of Health Sciences.
    Skov Jensen, Jørgen
    Statens Serum Institute, Denmark.
    Fredlund, Hans
    University Hospital, Örebro.
    A comparative study of three different PCR assays for detection of Mycoplasma genitalium in urogenital specimens from men and women2008In: Journal of Medical Microbiology, ISSN 0022-2615, E-ISSN 1473-5644, Vol. 57, p. 304-309Article in journal (Refereed)
    Abstract [en]

    The aim of this study was to compare conventional 16S rRNA gene PCR, real-time 16S rRNA gene PCR and real-time Mycoplasma genitalium adhesin protein (MgPa) gene PCR as detection methods for M. genitalium infection. The study also determined the prevalence of M. genitalium in male and female patients attending a sexually transmitted infections clinic in a rural area in the west of Sweden. First void urine (FVU) and/or urethral swabs were collected from 381 men, and FVU and/or cervical swabs and/or urethral swabs were collected from 298 women. A total of 213 specimens were used in the PCR comparative study: 98 consecutively sampled specimens from patients enrolled in the prevalence study, 36 consecutively sampled specimens from patients with symptoms of urethritis and 79 specimens from patients positive for M. genitalium by real-time MgPa gene PCR in the prevalence study. A true-positive M. genitalium DNA specimen was defined as either a specimen positive in any two PCR assays or a specimen whose PCR product was verified by DNA sequencing. The prevalence of M. genitalium infection in men and women was 27/381 (7.1 %) and 23/298 (7.7 %), respectively. In the PCR comparative study, M. genitalium DNA was detected in 61/76 (80.3 %) of true-positive specimens by conventional 16S rRNA gene PCR, in 52/76 (68.4 %) by real-time 16S rRNA gene PCR and in 74/76 (97.4 %) by real-time MgPa gene PCR. Real-time MgPa gene PCR thus had higher sensitivity compared with conventional 16S rRNA gene PCR and had considerably increased sensitivity compared with real-time 16S rRNA gene PCR for detection of M. genitalium DNA. Real-time MgPa gene PCR is well suited for the clinical diagnosis of M. genitalium.

  • 25.
    Eriksson, Andreas
    et al.
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Jonasson, Lena
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Lindahl, Tomas
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Chemistry. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre for Laboratory Medicine, Department of Clinical Chemistry.
    Hedbäck, Bo
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart Centre, Department of Cardiology.
    Whiss, Per
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Static platelet adhesion, flow cytometry and serum TXB2 levels for monitoring platelet inhibiting treatment with ASA and clopidogrel in coronary artery disease: a randomised cross-over study2009In: Journal of Translational Medicine, ISSN 1479-5876, E-ISSN 1479-5876, Vol. 7, no 42Article in journal (Refereed)
    Abstract [en]

    Background: Despite the use of anti-platelet agents such as acetylsalicylic acid (ASA) and clopidogrel in coronary heart disease, some patients continue to suffer from atherothrombosis. This has stimulated development of platelet function assays to monitor treatment effects. However, it is still not recommended to change treatment based on results from platelet function assays. This study aimed to evaluate the capacity of a static platelet adhesion assay to detect platelet inhibiting effects of ASA and clopidogrel. The adhesion assay measures several aspects of platelet adhesion simultaneously, which increases the probability of finding conditions sensitive for anti-platelet treatment. Methods: With a randomised cross-over design we evaluated the anti-platelet effects of ASA combined with clopidogrel as well as monotherapy with either drug alone in 29 patients with a recent acute coronary syndrome. Also, 29 matched healthy controls were included to evaluate intra-individual variability over time. Platelet function was measured by flow cytometry, serum thromboxane B-2 (TXB2)-levels and by static platelet adhesion to different protein surfaces. The results were subjected to Principal Component Analysis followed by ANOVA, t-tests and linear regression analysis. Results: The majority of platelet adhesion measures were reproducible in controls over time denoting that the assay can monitor platelet activity. Adenosine 5-diphosphate (ADP)-induced platelet adhesion decreased significantly upon treatment with clopidogrel compared to ASA. Flow cytometric measurements showed the same pattern (r(2) = 0.49). In opposite, TXB2-levels decreased with ASA compared to clopidogrel. Serum TXB2 and ADP-induced platelet activation could both be regarded as direct measures of the pharmacodynamic effects of ASA and clopidogrel respectively. Indirect pharmacodynamic measures such as adhesion to albumin induced by various soluble activators as well as SFLLRN-induced activation measured by flow cytometry were lower for clopidogrel compared to ASA. Furthermore, adhesion to collagen was lower for ASA and clopidogrel combined compared with either drug alone. Conclusion: The indirect pharmacodynamic measures of the effects of ASA and clopidogrel might be used together with ADP-induced activation and serum TXB2 for evaluation of anti-platelet treatment. This should be further evaluated in future clinical studies where screening opportunities with the adhesion assay will be optimised towards increased sensitivity to anti-platelet treatment.

  • 26.
    Falk, Magnus
    et al.
    Linköping University, Department of Biomedicine and Surgery, Dermatology. Linköping University, Faculty of Health Sciences.
    Ilias, Michail
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Wårdell, Karin
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Anderson, Chris
    Linköping University, Department of Biomedicine and Surgery, Dermatology. Linköping University, Faculty of Health Sciences.
    Phototesting with a divergent UVB beam in the investigation of anti-inflammatory effects of topically applied substances2003In: Photodermatology, Photoimmunology & Photomedicine, ISSN 0905-4383, E-ISSN 1600-0781, Vol. 19, no 4, p. 195-202Article in journal (Refereed)
    Abstract [en]

    Background: Phototesting based on a single exposure to a divergent ultraviolet B (UVB) beam with radially decreasing UVB doses can be used to determine an individual's minimal erythema dose (MED). Laser Doppler perfusion imaging (LDPI) data can be combined with dosimetry data to produce objective dose–response plots in addition to the MED. The aim of this study was to investigate whether the divergent beam protocol could be used to demonstrate and quantify the anti-inflammatory effects of clobetasol diproprionate (Dermovate®), pharmaceutical-grade acetone and a gel vehicle, applied after skin provocation by UVB.

    Method: Sixteen Caucasian subjects were illuminated with the divergent beam on three areas close together on the left side of their upper backs. Two of the provoked areas on each subject were treated with acetone, gel vehicle or Dermovate®, and one area was left untreated as a control. Skin blood perfusion was assessed 6 and 24 h after UVB illumination using LDPI. The reaction diameter, the mean perfusion, and the average dose–response plots for each group and treatment were extracted from the LDPI data.

    Results: Application of the topical steroid clobetasol diproprionate after UVB provocation markedly decreased the inflammatory response. Acetone and the gel vehicle also showed mild anti-inflammmatory effects in two of the parameters but not for the mean perfusion response. The mean diameter differences between controls and treated reactions had predominantly positive 99% confidence intervals. Analysis of the dose–response data at doses higher than the MED showed a linear relationship (0.89≤R2≤0.98) for all reactions but with lower gradients in treated reactions, mostly marked for clobetasol diproprionate.

    Conclusions:  The divergent beam protocol can be used to demonstrate and quantify the effects of topical agents on the UVB reaction, in terms of reaction diameter, mean perfusion and changes in dose–response characteristics. The dose–response approach seems to be applicable even in diagnostic testing of an individual patient's response to UVB.

  • 27.
    Falkeborn, Tina
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Hinkula, Jorma
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Olliver, Marie
    Karolinska Institute, Sweden.
    Lindberg, Alf
    Karolinska Institute, Sweden.
    Maltais, Anna-Karin
    Karolinska Institute, Sweden.
    The intranasal adjuvant Endocine((TM)) enhances both systemic and mucosal immune responses in aged mice immunized with influenza antigen2017In: Virology Journal, ISSN 1743-422X, E-ISSN 1743-422X, Vol. 14, article id 44Article in journal (Refereed)
    Abstract [en]

    Despite availability of annual influenza vaccines, influenza causes significant morbidity and mortality in the elderly. This is at least in part a result of immunosenescence; the age-dependent decrease in immunological competence that results in greater susceptibility to infections and reduced responses to vaccination. To improve protective immune responses in this age group, new vaccines strategies, such as the use of adjuvants, are needed. Here, we evaluated the mucosal vaccine adjuvant Endocine(TM), formulated with split influenza antigen and administered intranasally in aged (20-month old) mice. Humoral immune responses were assessed and compared to unadjuvanted intranasal and subcutaneous vaccines. We show that formulation with Endocine(TM) significantly enhances hemagglutination inhibition (HI) titers, as well as serum IgG and mucosal IgA antibody titers, compared to both types of unadjuvanted vaccines. Thus, our results indicate that intranasal vaccination with Endocine(TM) is a possible approach for the development of mucosal influenza vaccines for the elderly.

  • 28.
    Fernando, Germain J. P.
    et al.
    Vaxxas Pty Ltd, Australia.
    Hickling, Julian
    Working Tandem Ltd, England.
    Flores, Cesar M. Jayashi
    Vaxxas Pty Ltd, Australia.
    Griffin, Paul
    QIMR Berghofer Med Res Inst, Australia; Q Pharm Pry Ltd, Australia; Mater Hosp, Australia; Mater Res Inst, Australia; Univ Queensland, Australia.
    Anderson, Chris D
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Dermatology and Venerology.
    Skinner, S. Rachel
    Univ Sydney, Australia; Childrens Hosp Westmead, Australia.
    Davies, Cristyn
    Univ Sydney, Australia; Childrens Hosp Westmead, Australia.
    Witham, Katey
    Vaxxas Pty Ltd, Australia.
    Pryor, Melinda
    360Biolabs Pry Ltd, Australia.
    Bodle, Jesse
    Seqirus Pty Ltd, Australia.
    Rockman, Steve
    Seqirus Pty Ltd, Australia; Univ Melbourne, Australia.
    Frazer, Ian H.
    Not Found:[Fernando, Germain J. P.; Flores, Cesar M. Jayashi; Witham, Katey; Forster, Angus H.] Vaxxas Pty Ltd, Translat Res Inst, 37 Kent St, Brisbane, Qld 4102, Australia; [Hickling, Julian] Working Tandem Ltd, Cambridge, England; [Griffin, Paul] QIMR Berghofer Med Res Inst, Brisbane, Qld, Australia; [Griffin, Paul] Q Pharm Pry Ltd, Brisbane, Qld, Australia; [Griffin, Paul] Mater Hosp, Dept Med and Infect Dieases, Brisbane, Qld, Australia; [Griffin, Paul] Mater Res Inst, Brisbane, Qld, Australia; [Griffin, Paul] Univ Queensland, Brisbane, Qld, Australia; [Anderson, Christopher D.] Linkoping Univ, Dept Clin and Expt Med, Fac Hlth Sci, Linkoping, Sweden; [Anderson, Christopher D.] Heart and Med Ctr, Dept Dermatol and Venereol, Region Ostergotland, Sweden; [Skinner, S. Rachel; Davies, Cristyn] Univ Sydney, Sydney Med Sch, Discipline Child and Adolescent Hlth, Sydney, NSW, Australia; [Skinner, S. Rachel; Davies, Cristyn] Childrens Hosp Westmead, Sydney, NSW, Australia; [Pryor, Melinda] 360Biolabs Pry Ltd, Burnet Inst, Melbourne, Vic, Australia; [Bodle, Jesse; Rockman, Steve] Seqirus Pty Ltd, Melbourne, Vic, Australia; [Rockman, Steve] Univ Melbourne, Melbourne, Vic, Australia;.
    Forster, Angus H.
    Vaxxas Pty Ltd, Australia.
    Safety, tolerability, acceptability and immunogenicity of an influenza vaccine delivered to human skin by a novel high-density microprojection array patch (Nanopatch (TM))2018In: Vaccine, ISSN 0264-410X, E-ISSN 1873-2518, Vol. 36, no 26, p. 3779-3788Article in journal (Refereed)
    Abstract [en]

    Background: Injection using needle and syringe (Namp;S) is the most widely used method for vaccination, but requires trained healthcare workers. Fear of needles, risk of needle-stick injury, and the need to reconstitute lyophilised vaccines, are also drawbacks. The Nanopatch (NP) is a microarray skin patch comprised of a high-density array of microprojections dry-coated with vaccine that is being developed to address these shortcomings. Here we report a randomised, partly-blinded, placebo-controlled trial that represents the first use in humans of the NP to deliver a vaccine. Methods: Healthy volunteers were vaccinated once with one of the following: (1) NPs coated with split inactivated influenza virus (A/California/07/2009 [H1N1], 15 mu g haemagglutinin (HA) per dose), applied to the volar forearm (NP-HAIFA), n = 15; (2) NPs coated with split inactivated influenza virus (A/California/07/2009 11-11N1 I, 15 mu g HA per dose), applied to the upper arm (NP-HA/UA), n = 15; (3) Fluvaxe (R) 2016 containing 15 mu g of the same H1N1 HA antigen injected intramuscularly (IM) into the deltoid (IM-HA/D), n = 15; (4) NPs coated with excipients only, applied to the volar forearm (NP-placebo/FA), n = 5; (5) NPs coated with excipients only applied to the upper arm (NP-placebo/UA), n = 5; or (6) Saline injected IM into the deltoid (IM-placebo/D), n = 5. Antibody responses at days 0, 7, and 21 were measured by haemagglutination inhibition (HAI) and microneutralisation (MN) assays. Findings: NP vaccination was safe and acceptable; all adverse events were mild or moderate. Most subjects (55%) receiving patch vaccinations (HA or placebo) preferred the NP compared with their past experience of IM injection with Namp;S (preferred by 24%). The antigen-vaccinated groups had statistically higher HAI titres at day 7 and 21 compared with baseline (p amp;lt; 0.0001), with no statistical differences between the treatment groups (p amp;gt; 0.05), although the group sizes were small. The geometric mean HAI titres at day 21 for the NP-HA/FA, NP-HA/UA and IM-HA/D groups were: 335 (189-593 95% CI), 160 (74-345 95% CI), and 221 (129-380 95% CI) respectively. A similar pattern of responses was seen with the MN assays. Application site reactions were mild or moderate, and more marked with the influenza vaccine NPs than with the placebo or IM injection. Interpretation: Influenza vaccination using the NP appeared to be safe, and acceptable in this first time in humans study, and induced similar immune responses to vaccination by IM injection. (C) 2018 The Author(s). Published by Elsevier Ltd.

  • 29.
    Gupta, Shipra
    et al.
    Jamia Hamdard, India.
    Krishnan, Anuja
    Jamia Hamdard, India.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Kumar, Praveen
    Kalawati Saran Childrens Hospital, India.
    Aneja, Satinder
    Kalawati Saran Childrens Hospital, India.
    Ray, Pratima
    Jamia Hamdard, India.
    Changing pattern of prevalence, genetic diversity, and mixed infections of viruses associated with acute gastroenteritis in pediatric patients in New Delhi, India2018In: Journal of Medical Virology, ISSN 0146-6615, E-ISSN 1096-9071, Vol. 90, no 3, p. 469-476Article in journal (Refereed)
    Abstract [en]

    There are very few studies that have assessed multiple viral agents causing Acute-Gastroenteritis (AGE) in India. The present study compared the changing pattern of prevalence and genetic diversity of five enteric viruses associated with acute-diarrhea in Delhi children within a gap of 5 years. Fecal samples were collected from diarrheal children (amp;lt;4 years) during two winter seasons: year 2009-2010 (n=59) and year 2014-2015 (n=85). Samples were individually tested for rotavirus-A, norovirus, astrovirus, adenovirus, and sapovirus using EIA/RT-PCR and genetically characterized by phylogenetic analysis. Rotavirus was the most predominant (54.9%) virus followed by norovirus (25.7%), astrovirus (8.3%), and adenovirus (4.9%) with rare detection of sapovirus (0.7%). While detection rate increased for both rotavirus (49.2-58.8%) and astrovirus (5.1-10.6%), norovirus detection rate decreased (30.5-22.4%) from 2009 to 2015. During the same time period, adenovirus detection remained low (4.7-5.1%). Interestingly, mixed infections increased from 8.5% to 16.5% after 5 years. G1P[8] rotavirus strain was found most predominant (40%). Both type-1 and 8 astroviruses were detected. Single sapovirus detected was of genotype GII.1. Both GI (GI.5, GI.3) and GII (GII.1, GII.4, GII.7, GII.21, GII.13) genogroups of norovirus were detected. Of particular significance was the first detection of other NoV genotypes (besides GII.4 and GI.3) in Delhi. This is also the first report of NoV GI.5 from India. A change in prevalence pattern and increased diversity from 2009 to 2015 emphasizes the need for continued enteric virus surveillance to help measure the impact of new diarrhea vaccine(s) introduced in India.

  • 30.
    Hagbom, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Rotavirus Disease Mechanisms Diarrhea, Vomiting and Inflammation: How and Why2015Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rotavirus infections cause diarrhea and vomiting that can lead to severe dehydration. Despite extensive tissue damage and cell death, the inflammatory response is very limited. The focus of this thesis was to study pathophysiological mechanisms behind diarrhea and vomiting during rotavirus infection and also to investigate the mechanism behind the limited inflammatory response.

    An important discovery in this thesis was that rotavirus infection and the rotavirus toxin NSP4 stimulate release of the neurotransmitter serotonin from intestinal sensory enterochromaffin cells, in vitro and ex vivo. Interestingly, serotonin is known to be a mediator of both diarrhea and vomiting. Moreover, mice pups infected with rotavirus responded with central nervous system (CNS) activation in brain structures associated with vomiting, thus indicating a cross-talk between the gut and brain in rotavirus disease.

    Our finding that rotavirus infection activates the CNS led us to address the hypothesis that rotavirus infection not only activates the vagus nerve to stimulate vomiting, but also suppresses the inflammatory response via the cholinergic anti-inflammatory pathway, both of which are mediated by activated vagal afferent nerve signals into the brain stem. We found that mice lacking an intact vagus nerve, and mice lacking the α7 nicotine acetylcholine receptor (nAChR), being involved in cytokine suppression from macrophages, responded with a higher inflammatory response.

    Moreover, stimulated cytokine release from macrophages, by the rotavirus toxin NSP4, could be attenuated by nicotine, an agonist of the α7 nAChR. Thus, it seems most reasonable that the cholinergic anti-inflammatory pathway contributes to the limited inflammatory response during rotavirus infection. Moreover, rotavirus-infected mice displayed increased intestinal motility at the onset of diarrhea, which was not associated with increased intestinal permeability. The increased motility and diarrhea in infant mice could be attenuated by drugs acting on the enteric nervous system, indicating the importance and contribution of nerves in the rotavirus mediated disease.

    In conclusion, this thesis provides further insight into the pathophysiology of diarrhea and describe for the first time how rotavirus and host cross-talk to induce the vomiting reflex and limit inflammation. Results from these studies strongly support our hypothesis that serotonin and activation of the enteric nervous system and CNS contributes to diarrhea, vomiting and suppression of the inflammatory response in rotavirus disease.

    List of papers
    1. Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting
    Open this publication in new window or tab >>Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting
    Show others...
    2011 (English)In: PLOS PATHOGENS, ISSN 1553-7366, Vol. 7, no 7Article in journal (Refereed) Published
    Abstract [en]

    otavirus (RV) is the major cause of severe gastroenteritis in young children. A virus-encoded enterotoxin, NSP4 is proposed to play a major role in causing RV diarrhoea but how RV can induce emesis, a hallmark of the illness, remains unresolved. In this study we have addressed the hypothesis that RV-induced secretion of serotonin (5-hydroxytryptamine, 5-HT) by enterochromaffin (EC) cells plays a key role in the emetic reflex during RV infection resulting in activation of vagal afferent nerves connected to nucleus of the solitary tract (NTS) and area postrema in the brain stem, structures associated with nausea and vomiting. Our experiments revealed that RV can infect and replicate in human EC tumor cells ex vivo and in vitro and are localized to both EC cells and infected enterocytes in the close vicinity of EC cells in the jejunum of infected mice. Purified NSP4, but not purified virus particles, evoked release of 5-HT within 60 minutes and increased the intracellular Ca(2+) concentration in a human midgut carcinoid EC cell line (GOT1) and ex vivo in human primary carcinoid EC cells concomitant with the release of 5-HT. Furthermore, NSP4 stimulated a modest production of inositol 1,4,5-triphosphate (IP(3)), but not of cAMP. RV infection in mice induced Fos expression in the NTS, as seen in animals which vomit after administration of chemotherapeutic drugs. The demonstration that RV can stimulate EC cells leads us to propose that RV disease includes participation of 5-HT, EC cells, the enteric nervous system and activation of vagal afferent nerves to brain structures associated with nausea and vomiting. This hypothesis is supported by treating vomiting in children with acute gastroenteritis with 5-HT(3) receptor antagonists.

    Place, publisher, year, edition, pages
    Public Library of Science (PLoS), 2011
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-69989 (URN)10.1371/journal.ppat.1002115 (DOI)000293339300012 ()
    Note
    Original Publication: Marie Hagbom, Claudia Istrate, David Engblom, Thommie Karlsson, Jesus Rodriguez-Diaz, Javier Buesa, John A Taylor, Vesa Loitto, Karl-Eric Magnusson, Hakan Ahlman, Ove Lundgren and Lennart Svensson, Rotavirus Stimulates Release of Serotonin (5-HT) from Human Enterochromaffin Cells and Activates Brain Structures Involved in Nausea and Vomiting, 2011, PLOS PATHOGENS, (7), 7, . http://dx.doi.org/10.1371/journal.ppat.1002115 Licensee: Public Library of Science (PLoS) http://www.plos.org/Available from: 2011-08-12 Created: 2011-08-12 Last updated: 2015-05-13
    2. Rotavirus Infection Increases Intestinal Motility but Not Permeability at the Onset of Diarrhea
    Open this publication in new window or tab >>Rotavirus Infection Increases Intestinal Motility but Not Permeability at the Onset of Diarrhea
    Show others...
    2014 (English)In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 88, no 6, p. 3161-3169Article in journal (Refereed) Published
    Abstract [en]

    The disease mechanisms associated with onset and secondary effects of rotavirus (RV) diarrhea remain to be determined and may not be identical. In this study, we investigated whether onset of RV diarrhea is associated with increased intestinal permeability and/or motility. To study the transit time, fluorescent fluorescein isothiocyanate (FITC)-dextran was given to RV-infected adult and infant mice. Intestinal motility was also studied with an opioid receptor agonist (loperamide) and a muscarinic receptor antagonist (atropine). To investigate whether RV increases permeability at the onset of diarrhea, fluorescent 4- and 10-kDa dextran doses were given to infected and noninfected mice, and fluorescence intensity was measured subsequently in serum. RV increased transit time in infant mice. Increased motility was detected at 24 h postinfection (h p.i.) and persisted up to 72 h p.i in pups. Both loperamide and atropine decreased intestinal motility and attenuated diarrhea. Analysis of passage of fluorescent dextran from the intestine into serum indicated unaffected intestinal permeability at the onset of diarrhea (24 to 48 h p.i.). We show that RV-induced diarrhea is associated with increased intestinal motility via an activation of the myenteric nerve plexus, which in turn stimulates muscarinic receptors on intestinal smooth muscles.

    Place, publisher, year, edition, pages
    American Society for Microbiology, 2014
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-105750 (URN)10.1128/JVI.02927-13 (DOI)000332126000010 ()
    Available from: 2014-04-07 Created: 2014-04-04 Last updated: 2017-12-05
    3. The Cholinergic Anti-Inflammatory Pathway Contributes to the Limited Inflammatory Response following Rotavirus Infection
    Open this publication in new window or tab >>The Cholinergic Anti-Inflammatory Pathway Contributes to the Limited Inflammatory Response following Rotavirus Infection
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Rotavirus causes acute gastroenteritis in young children and is characterized by severe diarrhoea and vomiting. Surprisingly, although rotavirus infection results in significant intestinal pathology, the inflammatory response is limited. We tested the novel hypothesis that rotavirus infection stimulates the cholinergic anti-inflammatory pathway to suppress gut inflammation. The role of the vagus nerve and the α7 nicotinic acetylcholine receptor (α7 nAChR) in rotavirus infection were explored in α7 nAChR gene-deficient mice, vagotomized mice and wild-type mice treated with the α7 nAChR antagonist mecamylamine. TNF-α, IL-1β and IL-6 were measured in serum, spleen, duodenum, jejunum and ileum at 48 hours post infection. To determine if modulation of the inflammatory response affects virus shedding, α7 nAChRs was blocked and virus quantified in faeces. To investigate if stimulation of α7 nAChRs could attenuate rotavirus toxin NSP4-induced cytokine release, mouse peritoneal- and human blood-macrophages were treated with nicotine before NSP4 stimulation.

    Our results shows that stimulation of the vagus nerve and α7 nAChRs attenuated the pro- inflammatory response during rotavirus infection and blockade of the α7 nAChR reduced virus shedding from infected mice. IL-6 was increased in duodenum (p<0.05) and serum (p<0.05) of vagotomized mice and in jejunum (p<0.05) and spleen (p<0.05) of α7 nAChR gene-deficient mice. Furthermore, IL-6 mRNA (p<0.01) and TNF-α mRNA (p<0.05) were increased in duodenum of vagotomized animals. Similarly, nicotine attenuated the release of TNF-α (p<0.05) and IL-6 (p<0.05) from macrophages stimulated by NSP4 in vitro, all suggesting that the cholinergic anti- inflammatory pathway contributes to attenuate inflammation during rotavirus infection.

    National Category
    Microbiology Cell and Molecular Biology
    Identifiers
    urn:nbn:se:liu:diva-117892 (URN)
    Available from: 2015-05-13 Created: 2015-05-13 Last updated: 2018-01-11Bibliographically approved
    4. Intracellularly expressed rotavirus NSP4 stimulates release of serotonin (5-HT) from human enterochromaffin cells
    Open this publication in new window or tab >>Intracellularly expressed rotavirus NSP4 stimulates release of serotonin (5-HT) from human enterochromaffin cells
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Rotavirus (RV) is associated with diarrhoea and vomiting, but the mechanisms behind these symptoms remain unresolved. While RV have been shown to infect and stimulate secretion of serotonin (5-hydroxytryptamine; 5-HT) from human enterochromaffin (EC) cells and to infect EC cells in the small intestine of mice, it remains to identify which intracellularly expressed viral protein (VP) being responsible for this novel property.

    To address this issue, human EC cells were transfected with small interfering RNA (siRNA) targeting the structural (VP4, VP6 and VP7) and the non-structural protein 4 (NSP4) followed by infection with Rhesus rotavirus (RRV). siRNA specific to NSP4 (siRNANSP4) significantly attenuated secretion of 5-HT compared to siRNAVP4, siRNAVP6 , siRNAVP7 and non-targeting (Nt) siRNAnt. Intracellular calcium clamping with BABTA/AM showed that intracellularly expressed NSP4-stimulated secretion of 5-HT from EC cells was calcium-dependent. Furthermore RV down-regulated the 5-HT transporter (SERT) mRNA in ileum but not tryptophan hydroxylase 1 (TPH1) mRNA the rate-limiting enzyme for 5-HT synthesis. The unaffected expression of TPH1 mRNA in the intestinal segments suggests that release of 5- HT primarily originates from pre-made 5-HT rather than from newly synthesised 5-HT mRNA. Moreover, down-regulation of SERT mRNA in ileum presumably resulted in reduced re- uptake of 5-HT by SERT to EC cells and thus increased extracellular 5-HT in the small intestine. Moreover, 7/7 infant mice responded following intraperitoneal administration of 5-HT with rapid (<30 min) diarrhoea in dose-dependent manner. In the light of these results and the fact that both 5-HT and NSP4 can induce diarrhoea in mice, a disease mechanism to RV diarrhoea is proposed.

    National Category
    Microbiology Cell and Molecular Biology
    Identifiers
    urn:nbn:se:liu:diva-117893 (URN)
    Available from: 2015-05-13 Created: 2015-05-13 Last updated: 2018-01-11Bibliographically approved
  • 31.
    Hanssen, Anne-Merethe
    et al.
    UiT Arctic University of Norway, Norway.
    Kindlund, Bert
    University of Gothenburg, Sweden.
    Christian Stenklev, Niels
    UiT Arctic University of Norway, Norway.
    Furberg, Anne-Sofie
    University Hospital North Norway, Norway; UiT Arctic University of Norway, Norway.
    Fismen, Silje
    University Hospital North Norway, Norway.
    Slind Olsen, Renate
    Linköping University, Department of Medical and Health Sciences, Division of Drug Research. Linköping University, Faculty of Medicine and Health Sciences. Department Lab Med, Sweden.
    Johannessen, Mona
    UiT Arctic University of Norway, Norway.
    Ericson Sollid, Johanna Ulrica
    UiT Arctic University of Norway, Norway.
    Localization of Staphylococcus aureus in tissue from the nasal vestibule in healthy carriers2017In: BMC Microbiology, ISSN 1471-2180, E-ISSN 1471-2180, Vol. 17, article id 89Article in journal (Refereed)
    Abstract [en]

    Background: Colonization of the body is an important step in Staphylococcus aureus infection. S. aureus colonizes skin and mucous membranes in humans and several animal species. One important ecological niche of S. aureus is the anterior nares. More than 60% of the S. aureus in the nose are found in vestibulum nasi. Our aim was to describe the localization of S. aureus in nasal tissue from healthy carriers. Methods: Punch skin biopsies were taken from vestibulum nasi from healthy volunteers (S. aureus carriers and non-/intermittent carriers, n = 39) attending the population-based Tromso 6 study. The tissue samples were processed as frozen sections before immunostaining with a specific S. aureus antibody, and finally evaluated by a confocal laser-scanning microscope. Results: Our results suggest that S. aureus colonize both the upper and lower layers of the epidermis within the nasal epithelium of healthy individuals. The number of S. aureus in epidermis was surprisingly low. Intracellular localization of S. aureus in nasal tissue from healthy individuals was also detected. Conclusions: Knowledge of the exact localization of S. aureus in nasal tissue is important for the understanding of the host responses against S. aureus. Our results may have consequences for the eradication strategy of S. aureus in carriers, and further work can provide us with tools for targeted prevention of S. aureus colonisation and infection.

  • 32.
    Henningsson, Anna J
    et al.
    Ryhov County Hospital, Jönköping.
    Wilhelmsson, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Gyllemark, Paula
    Ryhov County Hospital, Jönköping.
    Kozak Ljunggren, Monika
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology.
    Matussek, Andreas
    Ryhov County Hospital, Jönköping.
    Nyman, Dag
    Ryhov County Hospital, Jönköping.
    Ekerfelt, Christina
    Bimelix Biomedical Laboratory, Mariehamn, Åland, Finland .
    Lindgren, Per-Eric
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Ryhov County Hospital, Jönköping.
    Forsberg, Pia
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Heart and Medicine Center, Department of Infectious Diseases. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Low risk of seroconversion or clinical disease in humans after a bite by an Anaplasma phagocytophilum-infected tick2015In: Ticks and Tick-borne Diseases, ISSN 1877-959X, E-ISSN 1877-9603, Vol. 6, no 6, p. 787-792Article in journal (Refereed)
    Abstract [en]

    The risk of contracting human granulocytic anaplasmosis (HGA) after a tick bite is mainly unknown. In this study we investigated the clinical and serological response in 30 humans bitten by ticks positive for Anaplasma phagocytophilum (Group A), 30 humans bitten by Borrelia burgdorferi sensu lato (s.l.)-positive ticks (Group B), and 30 humans bitten by ticks negative for both A. phagocytophilum and B. burgdorferi s.l. (Group C). Ticks, blood samples and questionnaires were collected from tick-bitten humans at 34 primary healthcare centres in Sweden and in the Åland Islands, Finland, at the time of the tick bite and after three months. A total of 2553 ticks detached from humans in 2007-2009 were analyzed by polymerase chain reaction, and 31 (1.2%) were positive for A. phagocytophilum, 556 (21.8%) were positive for B. burgdorferi s.l., and eight (0.3%) were co-infected by A. phagocytophilum and B. burgdorferi s.l. The overall prevalence of Anaplasma IgG antibodies in the included participants (n=90) was 17%, and there was no significant difference between the groups A-C. Only one of the participants (in Group C) showed a four-fold increase of IgG antibodies against A. phagocytophilum at the three-month follow-up, but reported no symptoms. The frequency of reported symptoms did not differ between groups A-C, and was unrelated to the findings of A. phagocytophilum and B. burgdorferi s.l. in the detached ticks. We conclude that the risk for HGA or asymptomatic seroconversion after a tick bite in Sweden or in the Åland Islands is low, even if the tick is infected by A. phagocytophilum.

  • 33.
    Hernandez, Frank J
    et al.
    Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Huang, Lingyan
    Integrated DNA Technologies (IDT), Coralville, IA, United States.
    Olson, Michael E.
    Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Powers, Kristy M.
    Integrated DNA Technologies (IDT), Coralville, IA, United States.
    Hernandez, Luiza I.
    Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Meyerholz, David K.
    Department of Pathology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Thedens, Daniel R.
    Department of Radiology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Behlke, Mark A.
    Integrated DNA Technologies (IDT), Coralville, IA, United States.
    Horswill, Alexander R.
    Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Mcnamara II, James O.
    Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Noninvasive imaging of Staphylococcus aureus infections with a nuclease-activated probe2014In: Nature Medicine, ISSN 1078-8956, E-ISSN 1546-170X, Vol. 20, no 3, p. 301-306Article in journal (Refereed)
    Abstract [en]

    Technologies that enable the rapid detection and localization of bacterial infections in living animals could address an unmet need for infectious disease diagnostics. We describe a molecular imaging approach for the specific, noninvasive detection of S. aureus based on the activity of the S. aureus secreted nuclease, micrococcal nuclease (MN). Several short synthetic oligonucleotides, rendered resistant to mammalian serum nucleases by various chemical modifications and flanked with a fluorophore and quencher, were activated upon degradation by purified MN and in S. aureus culture supernatants. A probe consisting of a pair of deoxythymidines flanked by several 2′-O-methyl-modified nucleotides was activated in culture supernatants of S. aureus but not in culture supernatants of several other pathogenic bacteria. Systemic administration of this probe to mice bearing S. aureus muscle infections resulted in probe activation at the infection sites in an MN-dependent manner. This new bacterial imaging approach has potential clinical applicability for infections with S. aureus and several other medically important pathogens. © 2014 Nature America, Inc.

  • 34.
    Hinkula, Jorma
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Karolinska Institute, Sweden.
    Devignot, Stephanie
    Philipps University of Marburg, Germany; Justus Liebig University, Germany.
    Åkerström, Sara
    National Vet Institute, Sweden.
    Karlberg, Helen
    Folkhälsomyndigheten, Sweden.
    Wattrang, Eva
    National Vet Institute, Sweden.
    Bereczky, Sandor
    Folkhalsomyndigheten, Sweden.
    Mousavi-Jazi, Mehrdad
    Folkhalsomyndigheten, Sweden.
    Risinger, Christian
    Department of Chemistry, University of Copenhagen, Frederiksberg, Denmark .
    Lindegren, Gunnel
    Folkhalsomyndigheten, Sweden.
    Vernersson, Caroline
    National Vet Institute, Sweden.
    Paweska, Janusz
    National Institute Communicable Disease, South Africa.
    Jansen van Vuren, Petrus
    National Institute Communicable Disease, South Africa.
    Blixt, Ola
    University of Copenhagen, Denmark.
    Brun, Alejandro
    Institute Nacl Invest and Tecnol Agriculture and Alimentaria, Spain.
    Weber, Friedemann
    Philipps University of Marburg, Germany; Justus Liebig University, Germany.
    Mirazimi, Ali
    Folkhälsomyndigheten, Sweden; National Vet Institute, Sweden; Karolinska Institute, Sweden.
    Immunization with DNA Plasmids Coding for Crimean-Congo Hemorrhagic Fever Virus Capsid and Envelope Proteins and/or Virus-Like Particles Induces Protection and Survival in Challenged Mice2017In: Journal of Virology, ISSN 0022-538X, E-ISSN 1098-5514, Vol. 91, no 10, article id UNSP e02076-16Article in journal (Refereed)
    Abstract [en]

    Crimean-Congo hemorrhagic fever virus (CCHFV) is a bunyavirus causing severe hemorrhagic fever disease in humans, with high mortality rates. The requirement of a high-containment laboratory and the lack of an animal model hampered the study of the immune response and protection of vaccine candidates. Using the recently developed interferon alpha receptor knockout (IFNAR(- / -)) mouse model, which replicates human disease, we investigated the immunogenicity and protection of two novel CCHFV vaccine candidates: a DNA vaccine encoding a ubiquitin-linked version of CCHFV Gc, Gn, and N and one using transcriptionally competent virus-like particles (tc-VLPs). In contrast to most studies that focus on neutralizing antibodies, we measured both humoral and cellular immune responses. We demonstrated a clear and 100% efficient preventive immunity against lethal CCHFV challenge with the DNA vaccine. Interestingly, there was no correlation with the neutralizing antibody titers alone, which were higher in the tc-VLP-vaccinated mice. However, the animals with a lower neutralizing titer, but a dominant cell-mediated Th1 response and a balanced Th2 response, resisted the CCHFV challenge. Moreover, we found that in challenged mice with a Th1 response (immunized by DNA/DNA and boosted by tc-VLPs), the immune response changed to Th2 at day 9 postchallenge. In addition, we were able to identify new linear B-cell epitope regions that are highly conserved between CCHFV strains. Altogether, our results suggest that a predominantly Th1-type immune response provides the most efficient protective immunity against CCHFV challenge. However, we cannot exclude the importance of the neutralizing antibodies as the surviving immunized mice exhibited substantial amounts of them. IMPORTANCE Crimean-Congo hemorrhagic fever virus (CCHFV) is responsible for hemorrhagic diseases in humans, with a high mortality rate. There is no FDAapproved vaccine, and there are still gaps in our knowledge of the immune responses to infection. The recently developed mouse models mimic human CCHF disease and are useful to study the immunogenicity and the protection by vaccine candidates. Our study shows that mice vaccinated with a specific DNA vaccine were fully protected. Importantly, we show that neutralizing antibodies are not sufficient for protection against CCHFV challenge but that an extra Th1-specific cellular response is required. Moreover, we describe the identification of five conserved B-cell epitopes, of which only one was previously known, that could be of great importance for the development of diagnostics tools and the improvement of vaccine candidates.

  • 35.
    Hinkula, Jorma
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Petkov, S
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Ljungberg, K
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Hallengärd, D
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Bråve, A
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Isaguliants, M
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Falkeborn, Tina
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Sharma, Sumit
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Liakina, V
    Faculty of Medicine, Vilnius University 2, 08661 Vilnius, Lithuania.
    Robb, M
    U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, 20892 MD, USA / Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, 20892 MD, USA.
    Eller, M
    U.S. Military HIV Research Program, Walter Reed Army Institute of Research, Silver Spring, 20892 MD, USA / Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, 20892 MD, USA.
    Moss, B
    Laboratory of Viral Diseases, National Institute of Allergy and Infectious Diseases, National Institutes of Health, Bethesda, 20892 MD, USA.
    Biberfeld, G
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Sandström, E
    Department of South Hospital, Karolinska Institutet, 11883 Stockholm, Sweden.
    Nilsson, C
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    Markland, K
    Clinical Research Center and Vecura, Karolinska University Hospital, 17176 Stockholm, Sweden.
    Blomberg, P
    Clinical Research Center and Vecura, Karolinska University Hospital, 17176 Stockholm, Sweden.
    Wahren, B
    Department of Microbiology Tumor and Cell Biology, Karolinska Institutet, 17177 Stockholm, Sweden.
    HIVIS-DNA or HIVISopt-DNA priming followed by CMDR vaccinia-based boosts induce both humoral and cellular murine immune responses to HIV.2017In: Heliyon, ISSN 2405-8440, Vol. 3, no 6, article id e00339Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: In order to develop a more effective prophylactic HIV-1 vaccine it is important optimize the components, improve Envelope glycoprotein immunogenicity as well as to explore prime-boost immunization schedules. It is also valuable to include several HIV-1 subtype antigens representing the world-wide epidemic.

    METHODS: HIVIS-DNA plasmids which include Env genes of subtypes A, B and C together with Gag subtypes A and B and RTmut/Rev of subtype B were modified as follows: the Envelope sequences were shortened, codon optimized, provided with an FT4 sequence and an immunodominant region mutated. The reverse transcriptase (RT) gene was shortened to contain the most immunogenic N-terminal fragment and fused with an inactivated viral protease vPR gene. HIVISopt-DNA thus contains fewer plasmids but additional PR epitopes compared to the native HIVIS-DNA. DNA components were delivered intradermally to young Balb/c mice once, using a needle-free Biojector® immediately followed by dermal electroporation. Vaccinia-based MVA-CMDR boosts including Env gene E and Gag-RT genes A were delivered intramuscularly by needle, once or twice.

    RESULTS: Both HIVIS-DNA and HIVISopt-DNA primed humoral and cell mediated responses well. When boosted with heterologous MVA-CMDR (subtypes A and E) virus inhibitory neutralizing antibodies were obtained to HIV-1 subtypes A, B, C and AE. Both plasmid compositions boosted with MVA-CMDR generated HIV-1 specific cellular responses directed against HIV-1 Env, Gag and Pol, as measured by IFNγ ELISpot. It was shown that DNA priming augmented the vector MVA immunological boosting effects, the HIVISopt-DNA with a trend to improved (Env) neutralization, the HIVIS-DNA with a trend to better (Gag) cell mediated immune reponses.

    CONCLUSIONS: HIVIS-DNA was modified to obtain HIVISopt-DNA that had fewer plasmids, and additional epitopes. Even with one DNA prime followed by two MVA-CMDR boosts, humoral and cell-mediated immune responses were readily induced by priming with either DNA construct composition. Priming by HIV-DNA augmented neutralizing antibody responses revealed by boosting with the vaccinia-based heterologous sequences. Cellular and antibody responses covered selected strains representing HIV-1 subtypes A, B, C and CRF01_AE. We assume this is related to the inclusion of heterologous full genes in the vaccine schedule.

  • 36.
    Hollén, Elisabet
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Coeliac Disease in Childhood: On the Intestinal Mucosa and the Use of Oats2006Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Coeliac disease (CD) is one of our most common chronic diseases in childhood. The disease causes an intense inflammation in the small intestinal mucosa after ingestion of gluten-containing cereals in genetically predisposed individuals. The mucosal lesion in CD is characterised by villous atrophy and crypt hyperplasia, and both the absorptive and the barrier functions of the enterocytes are disturbed. The treatment of CD is a life-long adherence to a gluten-free diet (GFD). The toxic fraction of wheat gluten is gliadin, and there are similar proteins in rye, barley and oats. In oats this protein is called avenin, and it is proposed to be less toxic than the others. The use of oats in CD has been debated, but it is now considered safe for the majority of both children and adults with CD.

    The aims of this thesis were to investigate the humoral and inflammatory reactions to oats in children with CD, and also to study the intestinal mucosa at different stages of the disease.

    In a retrospective study we found that children with CD had antibodies to oats avenin, and that the levels were significantly higher than in controls. The levels attenuated during GFD, and we also showed that there was no crossreactivity between antibodies to oats and gliadin.

    We then used our method for measuring antibodies to avenin in a randomised, double-blind trial of oats given to children with newly diagnosed CD. The children were given either a traditional GFD or a GFD supplemented with oats. There was a rapid decrease in antibody levels in both groups already after three months on diet, and at the end of the study period all but a few had normalised their levels. The same children were also studied using urinary nitric oxide (NO) products as markers for intestinal inflammation. Likewise, these values decreased significantly after three months. At the end of the study four children in the GFD-oats group and one in the standard GFD group still had extremely high concentrations of urinary NO metabolites. Taken together, these studies strengthen the clinical impression that oats can be tolerated by the majority of children with CD, but they also warrant a caution, since there seem to be children that do not tolerate oats in their diet.

    The structure and distribution of occludin and claudins 1-5, tight junction proteins known to play a crucial role in maintaining the barrier function, was studied in biopsy specimens from children at different stages of CD. There was an increased expression of occludin in untreated CD, which reflects the characteristics of crypt cell hyperplasia and altered barrier properties seen in active CD. The findings also indicate that gluten intake does not significantly influence the expression and distribution of claudins 1-5 in coeliac children.

    List of papers
    1. Antibodies to oat prolamines (avenins) in children with coeliac disease
    Open this publication in new window or tab >>Antibodies to oat prolamines (avenins) in children with coeliac disease
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    2003 (English)In: Scandinavian Journal of Gastroenterology, ISSN 0036-5521, Vol. 38, no 7, p. 742-746Article in journal (Refereed) Published
    Abstract [en]

    Background: The use of oats in a gluten-free diet for children with coeliac disease is presently under investigation. In this study we measured the content of antibodies to oat prolamines (avenin) in sera from coeliac children and reference children.

    Methods: Crude avenin was prepared by extraction with ethanol and salt-solution and used as antigen in a three-step ELISA. Sera from 81 children, including 34 children with verified coeliac disease, were analysed for both IgA and IgG antibodies to avenin and gliadin. Sera were also incubated with gliadin before exposure to avenin, and vice versa, to assess a possible cross-reaction between the species. Keyhole limpet hemocyanin (KLH) was used as a negative control.

    Results: Children with coeliac disease on a normal diet had significantly higher levels of antibodies to avenin, both IgG and IgA, than reference children ( P < 0.001) and the levels correlated positively with gliadin antibodies, especially of IgA-type ( r = 0.798). Both anti-avenin and anti-gliadin antibodies were only absorbed by the corresponding protein.

    Conclusions: Children with coeliac disease have antibodies to oat proteins at significantly higher levels than reference children. The absorption test did not indicate a cross-reactivity between the prolamines of wheat and oats. The method will be employed for repeated sampling of anti-avenin antibodies during a prospective interventional study with a gluten-free diet supplemented with oats.

    Keywords
    Anti-avenin Antibodies, Coeliac Disease, Oats
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14131 (URN)10.1080/00365520310003156 (DOI)
    Available from: 2006-11-06 Created: 2006-11-06 Last updated: 2009-08-18
    2. Coeliac children on a gluten-free diet with or without oats display equal anti-avenin antibody titres
    Open this publication in new window or tab >>Coeliac children on a gluten-free diet with or without oats display equal anti-avenin antibody titres
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    2006 (English)In: Scandinavian Journal of Gastroenterology, ISSN 0036-5521, Vol. 41, no 1, p. 42-47Article in journal (Refereed) Published
    Abstract [en]

    Objective. Recent studies report negligible toxicity of oats in the majority of coeliac disease (CD) patients. It has previously been shown that children with untreated CD have circulating antibodies to oats avenin. In this study we performed serial assessments of anti-avenin antibodies in children under investigation for CD on a gluten-free diet with or without oats.

    Material and methods. The study involved 116 children, randomized to a standard gluten-free diet or a gluten-free diet supplemented with oats. Sera were obtained from 86 children, 48 in the standard gluten-free group and 38 in the gluten-free oats group, of which 33 consumed at least 10 g of oats daily. IgA and IgG anti-avenin antibodies were monitored at 0, 3, 6 and 12 months. Nitric oxide metabolites were measured in 7 patients, with deviating antibody results.

    Results. There was a significant decrease in anti-avenin antibodies in both groups at the end as compared to the beginning of the study, (p<0.001), but no difference was found between the two groups. IgA titres already declined after 3 months. IgG titres, although significantly decreased, remained high in the majority of patients in both groups. Nitric oxide levels were high in four of the analysed samples.

    Conclusions. Oats per se, do not seem to produce a humoral immune reaction in children with CD when given in an otherwise gluten-free diet, indicating that the reaction requires gluten challenge. Anti-avenin antibodies were equal in the two study groups, and these findings strengthen the clinical impression that oats can be tolerated by the majority of patients with CD.

    Keywords
    Anti-avenin antibodies; avenin; coeliac disease; oats
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14132 (URN)10.1080/00365520510023945 (DOI)
    Available from: 2006-11-06 Created: 2006-11-06 Last updated: 2009-05-19
    3. Urinary nitric oxide during one year of gluten-free diet with or without oats in children with coeliac disease
    Open this publication in new window or tab >>Urinary nitric oxide during one year of gluten-free diet with or without oats in children with coeliac disease
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    2006 (English)In: Scandinavian Journal of Gastroenterology, ISSN 0036-5521, Vol. 41, no 11, p. 1272-1278Article in journal (Refereed) Published
    Abstract [en]

    Objective. Although in both adults and children with coeliac disease (CD) it is now recommended that oats be added to their gluten-free diet, there is still some controversy concerning the possible harmful effects of oats in some individuals. In this study concentrations of nitric oxide metabolites were repeatedly measured in the urine of children under investigation for CD, when on a gluten-free diet with or without oats.

    Material and methods. The study included 116 children, randomized to a standard gluten-free diet (GFD-std) or a gluten-free diet supplemented with wheat-free oat products (GFD-oats), over a one-year period. Small-bowel biopsy was performed at the beginning and end of the study. Morning urine samples were collected from 87 children and urinary nitrite/nitrate concentrations were monitored at 0, 3, 6, 9 and 12 months.

    Results. All patients were in clinical remission after the study period. There was a rapid decline in urinary nitrite/nitrate concentrations in both groups as early as after 3 months. No differences were seen between the study groups at any of the checkpoints. However, at the end of the study, the nitrite/nitrate values of 9 children in the GFD-oats group and 8 children in the GFD-std group had not normalized.

    Conclusions. Children with CD on a gluten-free diet with oats display a similar reduction in urinary nitrite/nitrate as those on a traditional gluten-free diet. Some children, however, still demonstrate high nitrite/nitrate excretion after one year on either diet, indicating that long-term follow-up studies of children on an oats-containing diet are needed.

    Keywords
    coeliac disease; NO; oats; urinary nitrite/nitrate
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-14133 (URN)10.1080/00365520600684563 (DOI)
    Available from: 2006-11-06 Created: 2006-11-06 Last updated: 2009-05-19
    4. Increased expression of tight junction associated occludin but not of claudins in untreated coeliac disease in children
    Open this publication in new window or tab >>Increased expression of tight junction associated occludin but not of claudins in untreated coeliac disease in children
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    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-14134 (URN)
    Available from: 2006-11-06 Created: 2006-11-06 Last updated: 2010-01-13
  • 37.
    Ihnatko, Robert
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Shaw, Edward
    Dep. Microbiology and Molecular Genetics, Oklahoma State University, USA.
    Toman, Rudolf
    Institute of Virology, Slovak Academy of Science, Bratislava, Slovakia.
    Proteome of Coxiella burnetii2012In: Coxiella burnetii: Recent Advances and New Perspectives in Research of the Q Fever Bacterium / [ed] Rudolf Toman, Robert A. Heinzen, James E. Samuel and Jean-Louis Mege, Springer-Verlag New York, 2012, Vol. 984, p. 105-130Chapter in book (Refereed)
    Abstract [en]

    Recent proteomic studies of C. burnetii, the etiological agent of Q fever, have brought a deeper insight into the pathogens physiology and offered new possibilities in investigations of inter- or intra-species relatedness. The data generated from these studies in conjunction with the current genomic sequence databases may reveal additional identities for conserved and unique C. burnetii biomarkers and aid in creating algorithms and/or databases that could develop into diagnostic and detection tools for the pathogen. Moreover, wide scale screening and further characterization of potential C. burnetii protein antigens along with a comprehensive evaluation of the humoral immune response will be of fundamental importance towards research and development of a safe and efficacious vaccine as well as improved serodiagnostic tests for rapid and sensitive detection of the Q fever pathogen. Given these advances, proteomics may make marked contributions to the improvement of human health protection against C. burnetii in the coming years.

  • 38.
    Ihnatko, Robert
    et al.
    Slovak Academy of Sciences, Institute of Virology, Laboratory for Diagnosis and Prevention of Rickettsial and Chlamydial Infections, Slovak Republic.
    Vadovič, Pavol
    Slovak Academy of Sciences, Institute of Virology, Laboratory for Diagnosis and Prevention of Rickettsial and Chlamydial Infections, Slovak Republic.
    Toman, Rudolf
    Slovak Academy of Sciences, Institute of Virology, Laboratory for Diagnosis and Prevention of Rickettsial and Chlamydial Infections, Slovak Republic.
    Proteins of Coxiella Burnetii and Analysis of their Function2011In: BSL3 and BSL4 Agents: Proteomics, Glycomics, and Antigenicity / [ed] Jiri Stulik, Rudolf Toman, Patrick Butaye and Robert G. Ulrich, Wiley-VCH Verlag GmbH & Co. KGaA , 2011, p. 145-151Chapter in book (Refereed)
  • 39.
    Ingberg, Edvin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Dock, Hua
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ström, Jakob O
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry. Vårdvetenskapligt Forskningscentrum/Centre for Health Sciences, Örebro University Hospital, Region Örebro Län, Örebro, Sweden / School of Health and Medical Sciences, Örebro University, Örebro, Sweden..
    Method parameters’ impact on mortality and variability in mouse stroke experiments: a meta-analysis2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6Article in journal (Refereed)
    Abstract [en]

    Although hundreds of promising substances have been tested in clinical trials, thrombolysis currently remains the only specifi c pharmacological treatment for ischemic stroke. Poor quality, e.g. low statistical power, in the preclinical studies has been suggested to play an important role in these failures. Therefore, it would be attractive to use animal models optimized to minimize unnecessary mortality and outcome variability, or at least to be able to power studies more exactly by predicting variability and mortality given a certain experimental setup. The possible combinations of methodological parameters are innumerous, and an experimental comparison of them all is therefore not feasible. As an alternative approach, we extracted data from 334 experimental mouse stroke articles and, using a hypothesis-driven meta-analysis, investigated the method parameters’ impact on infarct size variability and mortality. The use of Swiss and C57BL6 mice as well as permanent occlusion of the middle cerebral artery rendered the lowest variability of the infarct size while the emboli methods increased variability. The use of Swiss mice increased mortality. Our study offers guidance for researchers striving to optimize mouse stroke models.

  • 40.
    Ingberg, Edvin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Theodorsson, Elvar
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Chemistry.
    Theodorsson, Annette
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Neurosurgery.
    Ström, Jakob O
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Vårdvetenskapligt Forskningscentrum/Centre for Health Sciences, Örebro University Hospital, Region Örebro Län, Örebro, Sweden / School of Health and Medical Sciences, Örebro University, Örebro, Sweden..
    Effects of high and low 17β-estradiol doses on focal cerebral ischemia in rats2016Manuscript (preprint) (Other academic)
    Abstract [en]

    The majority of the numerous animal studies of the effects of estrogens on cerebral ischemia have reported neuroprotective results, but a few have shown increased damage. Differences in hormone administration methods, resulting in highly different 17β-estradiol levels, may explain the discrepancies in previously reported effects. The objective of the present study was to test the hypothesis that it is the delivered dose per se, and not the route and method of administration, that determines the effect, and that high doses are damaging while lower doses are protective. One hundred and twenty ovariectomized female Wistar rats (n=40 per group) were randomized into three groups, subcutaneously administered different doses of 17β-estradiol and subjected to transient middle cerebral artery occlusion. The modifi ed sticky tape test was performed after 24 h and the rats were subsequently sacrifi ced for infarct size measurements. In contrast to our hypothesis, a signifi cant negative correlation between 17β-estradiol dose and infarct size was found (p=0.018). Thus, no support was found for the hypothesis that 17β-estradiol can be both neuroprotective and neurotoxic merely depending on dose. In fact, on the contrary, the fi ndings indicate that the higher the dose of 17β-estradiol, the smaller the infarct.

  • 41.
    Iranpour, Mahmoud
    et al.
    National Microbiology Laboratory, Canada.
    Moghadam, Adel R.
    Islamic Azad University.
    Yazdi, Mina
    University of Tehran.
    Ande, Sudharsana R.
    University of Manitoba.
    Alizadeh, Javad
    University of Manitoba.
    Wiechec, Emilia
    Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science.
    Lindsay, Robbin
    National Microbiology Laboratory, Canada.
    Drebot, Michael
    National Microbiology Laboratory, Canada.
    Coombs, Kevin M.
    University of Manitoba.
    Ghavami, Saeid
    University of Manitoba.
    Apoptosis, autophagy and unfolded proteinresponse pathways in Arbovirus replicationand pathogenesis2016In: Expert Reviews in Molecular Medicine, ISSN 1462-3994, E-ISSN 1462-3994, Vol. 18, no e1, p. 21-Article, review/survey (Refereed)
    Abstract [en]

    Arboviruses are pathogens that widely affect the health of people in different communities around the world. Recently, a few successful approaches toward production of effective vaccines against some of these pathogens have been developed, but treatment and prevention of the resulting diseases remain a major health and research concern. The arbovirus infection and replication processes are complex, and many factors are involved in their regulation. Apoptosis, autophagy and the unfolded protein response (UPR) are three mechanisms that are involved in pathogenesis of many viruses. In this review, we focus on the importance of these pathways in the arbovirus replication and infection processes. We provide a brief introduction on how apoptosis, autophagy and the UPR are initiated and regulated, and then discuss the involvement of these pathways in regulation of arbovirus pathogenesis.

  • 42.
    Jakobsson, Tell
    Linköping University, Department of Clinical and Experimental Medicine, Obstetrics and gynecology. Linköping University, Faculty of Health Sciences.
    Lactobacillus iners and the normal vaginal flora2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [fi]

    The ecological niche of the vagina contains a large number of different microbes that are constantly interacting with each other and the host. Culture methods have not been sufficient in order to resolve the complexity of the normal vaginal flora. Further, the methods for delineating normal flora from not normal flora are not easily handled and are traditionally not based on culture but on microscopy of elements of the vaginal fluid. In the work presented in this thesis, an international collaboration was established that pin-pointed some of the difficulties in classifying vaginal floras, including staining, sampling, and discordance when lactobacilli are few in number, and that emphasized the importance of the size of the vision field in microscopes. As lactobacilli are prominent members of the normal vaginal flora they need to be carefully classified if further work towards more robust scoring tools is to be achieved.

    Phenotypic methods have not been able to separate the closely related Lactobacillus species of the vagina. Progress in molecular biology has provided possibilities to characterize these lactobacilli, which are mainly from the Lactobacillus acidophilus group. In this work a large number of strains collected by true random sampling were subjected to RAPD-PCR, TTGE and multiplex PCR for species identification. The major species found were L. crispatus, L. gasseri and L. jensenii and the recently described L. iners. The presence of L. iners has not been detected in previous studies due to its special nutrient requirements. Development of pyrosequencing technology also made it possible to match signatures of the two variable regions V1 and V3 of the 16S rRNA gene of the vaginal lactobacilli and identify them to the species level in a high throughput manner. The study confirmed that the dominating flora in women with normal vaginal flora comprises the four species mentioned previously. Repetitive sampling during IVF-treatment with highly varying oestrogen levels demonstrates changes that possibly occur during changes in the natural life cycle. Furthermore, L. iners was found to be the first species to be established after spontaneously resolved or treated Bacterial Vaginosis.

    These findings can be of help in developing new strategies for regaining and retaining the normal vaginal flora.

    List of papers
    1. An international study of the inter-observer variation between the interpretations of vaginal smear criteria of Bacterial Vaginosis
    Open this publication in new window or tab >>An international study of the inter-observer variation between the interpretations of vaginal smear criteria of Bacterial Vaginosis
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    2002 (English)In: APMIS, ISSN 1600-0463, Vol. 110, no 11, p. 811-818Article in journal (Refereed) Published
    Abstract [en]

    An international workshop on vaginal smear-based diagnosis of bacterial vaginosis was organized where 13 investigators scoring 258 slides with smears from vaginal fluid. Interobserver reproducibility of interpretations of Nugent scores, Hay/Ison scores and wet smear scores for the diagnosis of bacterial vaginosis was shown to be high. Detailed analysis of individual scoring results however indicated that basic standards of quality control to ensure robust individual readings of slides must be adhered to.

    Keywords
    Bacterial vaginosis, diagnosis, criteria
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13050 (URN)10.1034/j.1600-0463.2002.1101107.x (DOI)
    Available from: 2008-03-19 Created: 2008-03-19 Last updated: 2013-09-12
    2. Vaginal Lactobacillus flora of healthy Swedish women
    Open this publication in new window or tab >>Vaginal Lactobacillus flora of healthy Swedish women
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    2002 (English)In: Journal of clinical microbiology, ISSN 0095-1137, Vol. 40, no 8, p. 2746-2749Article in journal (Refereed) Published
    Abstract [en]

    Species of the Lactobacillus acidophilus complex are generally considered to constitute most of the vaginal Lactobacillus flora, but the flora varies between studies. However, this may be due to difficulties in identifying the closely related species within the L. acidophilus complex by using traditional methods and to variations in the vaginal status of the participants. Two hundred two isolates from the vaginal fluids of 23 Swedish women without bacterial vaginosis, as defined by the criteria of Nugent et al. (R. P. Nugent, M. A. Krohn, and S. L. Hillier, J. Clin. Microbiol. 29:297-301, 1991), were typed by randomly amplified polymorphic DNA (RAPD) analysis and identified to the species level by temporal temperature gradient gel electrophoresis, multiplex PCR, and 16S ribosomal DNA sequencing. The vaginal flora of most participants was dominated by a single RAPD type, but five of them harbored two RAPD types representing two different species or strains. The most frequently occurring species were Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners, and Lactobacillus jensenii. L. iners has not previously been reported as one of the predominant Lactobacillus species in the vagina.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13051 (URN)10.1128/JCM.40.8.2746-2749.2002 (DOI)
    Available from: 2008-03-19 Created: 2008-03-19 Last updated: 2018-02-02
    3. Identification of randomly selected colonies of Lactobacilli from normal vaginal fluid by pyrosequencing of the 16S rDNA Variable V1 and V3 Regions
    Open this publication in new window or tab >>Identification of randomly selected colonies of Lactobacilli from normal vaginal fluid by pyrosequencing of the 16S rDNA Variable V1 and V3 Regions
    2002 (English)In: Acta Pathologica, Microbiologica et Immunologica Scandinavica (APMIS), ISSN 0903-4641, E-ISSN 1600-0463, Vol. 110, no 11, p. 802-810Article in journal (Refereed) Published
    Abstract [en]

    The present study aimed to characterize lactobacilli in vaginal fluid from 23 adult healthy women by using high-throughput DNA sequencing for identification of a large number of randomly selected colonies appearing on Rogosa and blood agar. The typing method was based on broad-range PCR of 16S rRNA gene variable regions V1 and V3, pyrosequencing, and classification of the fragments by alignment with NCBI-catalogued sequences and type strain sequences. Four major groups of sequences were found among the 402 isolates clearly corresponding to Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners and Lactobacillus jensenii when compared to the sequences obtained for type strains. Our results indicate that pyrosequencing of 16S rRNA gene fragments as used here is a fast and reliable method well suited for identification to the species level, even within the Lactobacillus acidophilus complex.

    Keywords
    Lactobacillus, vaginal fluid, 16S rRNA genes, pyrosequencing
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13052 (URN)10.1034/j.1600-0463.2002.1101106.x (DOI)
    Available from: 2008-03-19 Created: 2008-03-19 Last updated: 2017-12-13Bibliographically approved
    4. Lactobacillus iners: a marker of changes in the vaginal flora?
    Open this publication in new window or tab >>Lactobacillus iners: a marker of changes in the vaginal flora?
    2007 (English)In: Journal of Clinical Microbiology, ISSN 0095-1137, E-ISSN 1098-660X, Vol. 45, no 9, p. 3145-Article in journal, Letter (Other academic) Published
    Place, publisher, year, edition, pages
    American Society for Microbiology, 2007
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13053 (URN)10.1128/JCM.00558-07 (DOI)000249506900072 ()
    Available from: 2008-03-19 Created: 2008-03-19 Last updated: 2017-12-13
    5. The predominant Human vaginal Lactobacillus flora during IVF treatment
    Open this publication in new window or tab >>The predominant Human vaginal Lactobacillus flora during IVF treatment
    2008 (English)In: Journal of Clinical Microbiology, ISSN 0095-1137, E-ISSN 1098-660X, Vol. 7, no 14, p. 1-9Article in journal (Refereed) Submitted
    Abstract [en]

    Background: Signature matching of nucleotide sequences in the V1 and V3 regions 16S rRNA genes using pyrosequencing technology is a powerful tool for typing vaginal Lactobacilli to the species level and has been used for investigating the vaginal microbial niche.

    Methods: This study has characterized the normal cultivable vaginal Lactobacillus flora at varying estradiol levels in plasma; the study comprised 17 patients undergoing ovarian stimulation for In Vitro Fertilization (IVF) treatment. The vaginal status of each participant was initially assessed as normal according to Amsel and Nugent criteria.

    Results: L. crispatus, L. gasseri and/or L. jensenii were present in 10 of the patients throughout the study period, and little variation among these three species was encountered in individual patients. The flora of three women was dominated by L. delbrüeckii, L. rhamnosus or L. vaginalis. One woman exhibited a dominance of L. iners. The flora of the remaining three women were initially dominated by L. rhamnosus or L. reuteri, but as their estrogen levels rose, their flora composition altered, to become dominated by one of the three species most common in a normal, healthy vagina.

    Conclusion: Signature matching of nucleotide sequences in the V1 and V3 regions of 16S rRNA genes is a discriminative tool for the study of vaginal Lactobacilli and can be used to track the Lactobacillus flora under a variety of physiological conditions.

    Place, publisher, year, edition, pages
    American Society for Microbiology, 2008
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-13054 (URN)10.1186/1476-0711-7-14 (DOI)
    Available from: 2008-03-19 Created: 2008-03-19 Last updated: 2019-04-02Bibliographically approved
  • 43.
    Kalsum, Sadaf
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Characterizing phenotypes of Mycobacterium tuberculosis and exploring anti-mycobacterial compounds through high content screening2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Tuberculosis (TB), an airborne disease and one of the top 10 causes of death globally, is caused by Mycobacterium tuberculosis (Mtb). Current standard therapy for TB treatment includes multiple drugs for a period of at least 6 months. The long therapy duration is to sterilize a small sub-population of drug-tolerant bacteria, a characteristic related to biofilm formation, which otherwise responsible for disease relapse. On the other hand, because of such a long treatment period, patient adherence to therapy becomes difficult, which results in the emergence of multidrug-resistant (MDR) or, in worst cases, extensively drug-resistant (XDR)-TB. TB is primarily a disease of lungs and alveolar macrophages are one of the first host cell types to encounter Mtb following aerosol transmission. A well-established role of macrophages in immune defense is phagocytosis, but recent studies also demonstrated that upon interaction with large aggregates of microbes or cord-forming mycobacterial species, macrophages could produce extracellular traps known as macrophage extracellular traps (METs). METs have a DNA backbone with embeds histones and could trap a wide range of microorganisms, but may or may not be able to kill them. Natural products are always a promising starting point for drug discovery because of their wide range of activity. A large number of world’s population is still using extracts from different parts of plants as the primary source of medicines against diseases including TB. Today much effort is being invested by academia in screening campaigns that allows for fast discovery of new active compounds. Thanks to the use of automated technology such as automated microscopy or automated image analysis (known as high content screening, HCS) phenotypic drug discovery has become easier to perform. Therefore, the identification of highly effective compounds to combat infectious diseases like TB can be facilitated by the use of host-pathogen assays at the early stages of drug screening studies.

    This thesis describes the characterization and antibiotic sensitivity of different phenotypes of Mtb namely planktonic, cord-forming and biofilm-producing phenotypes that arise due to different culture conditions. The culture of Mtb with a high percentage of a detergent (Tween-80) and standing condition promoted planktonic phenotype while a culture with a low amount of Tween-80 and more aeration due to shaking promoted cording and biofilm phenotypes. Primary human macrophages upon interaction with the shaken culture of wild-type Mtb died by releasing METs. Whereas, the shaken cultures of early secreted antigenic target-6 (ESAT-6), an important virulence factor of Mtb, deletion mutant strain could not induce MET formation showing that the cord formation is related to virulence. Moreover, the biofilm phenotype of Mtb is more tolerant to two first-line antibiotics isoniazid (INH) and rifampicin (RIF) as compared to cording and planktonic phenotypes which demand a search of more effective TB therapy. A screening campaign based on a whole-cell assay using different ethanolic crude extracts of many African plants lead to the discovery of a hit, i.e., a chloroform fraction of Khaya senegalensis bark, which showed non-significant inhibition of intracellular growth of a virulent strain of Mtb was selected for further purification and evaluation. Lastly, we have also developed and validated an HCS assay to explore new compounds against intracellular Mtb in human macrophages. INH and RIF, which were found most effective in our system were used in a combination as a positive control to calculate a Z’ factor value, which confirmed our assay to be suitable for HCS.

    In conclusion, this thesis not only highlights the biology of TB infection, but also discusses the development of a pathophysiologically relevant assay that can be used in the identification of novel compound(s) that has either direct anti-mycobacterial activity (antibiotic), acts by stimulating the host cell immune mechanisms (immunomodulator) or acts by counteracting virulence factors (virulence blocker).  

    List of papers
    1. The Cording Phenotype of Mycobacterium tuberculosis Induces the Formation of Extracellular Traps in Human Macrophages
    Open this publication in new window or tab >>The Cording Phenotype of Mycobacterium tuberculosis Induces the Formation of Extracellular Traps in Human Macrophages
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    2017 (English)In: Frontiers in Cellular and Infection Microbiology, E-ISSN 2235-2988, Vol. 7, article id 278Article in journal (Refereed) Published
    Abstract [en]

    The causative agent of tuberculosis, Mycobacterium tuberculosis, shares several characteristics with organisms that produce biofilms during infections. One of these is the ability to form tight bundles also known as cords. However, little is known of the physiological relevance of the cording phenotype. In this study, we investigated whether cord-forming M. tuberculosis induce the formation of macrophage extracellular traps (METs) in human monocyte-derived macrophages. Macrophages have previously been shown to produce extracellular traps in response to various stimuli. We optimized bacterial culturing conditions that favored the formation of the cord-forming phenotype as verified by scanning electron microscopy. Microscopy analysis of METs formation during experimental infection of macrophages with M. tuberculosis revealed that cord-forming M. tuberculosis induced significantly more METs compared to the non-cording phenotype. Deletion of early secreted antigenic target-6 which is an important virulence factor of M. tuberculosis, abrogated the ability of the bacteria to induce METs. The release of extracellular DNA from host cells during infection may represent a defense mechanism against pathogens that are difficult to internalize, including cord-forming M. tuberculosis.

    Place, publisher, year, edition, pages
    FRONTIERS MEDIA SA, 2017
    Keywords
    Mycobacterium tuberculosis; macrophage extracellular traps (METs); cording; Tween-80; virulence; early secreted antigenic target-6 (ESAT-6)
    National Category
    Microbiology in the medical area
    Identifiers
    urn:nbn:se:liu:diva-139276 (URN)10.3389/fcimb.2017.00278 (DOI)000404073500001 ()
    Note

    Funding Agencies|Swedish Research Council [2012-3349, 2015-02593]; Swedish Heart Lung Foundation [20130685, 20150709]

    Available from: 2017-07-07 Created: 2017-07-07 Last updated: 2019-01-07
    2. Antimycobacterial activity of selected medicinal plants traditionally used in Sudan to treat infectious diseases
    Open this publication in new window or tab >>Antimycobacterial activity of selected medicinal plants traditionally used in Sudan to treat infectious diseases
    Show others...
    2014 (English)In: Journal of Ethnopharmacology, ISSN 0378-8741, E-ISSN 1872-7573, Vol. 157, p. 134-139Article in journal (Refereed) Published
    Abstract [en]

    Ethnopharmacological relevance: The emergence of multidrug-resistant strains of Mycobacterium tuberculosis underscores the need for continuous development of new and efficient methods to determine the susceptibility of isolates of Mycobacterium tuberculosis in the search for novel antimycobacterial agents. Natural products constitute an important source of new drugs, and design and implementation of antimycobacterial susceptibility testing methods are necessary to evaluate the different extracts and compounds. In this study we have explored the antimycobacterial properties of 50 ethanolic extracts from different parts of 46 selected medicinal plants traditionally used in Sudan to treat infectious diseases. Materials and methods: Plants were harvested and ethanolic extracts were prepared. For selected extracts, fractionation with hydrophilic and hydrophobic solvents was undertaken. A luminometry-based assay was used for determination of mycobacterial growth in broth cultures and inside primary human macrophages in the presence or absence of plant extracts and fractions of extracts. Cytotoxicity was also assessed for active fractions of plant extracts. Results: Of the tested extracts, three exhibited a significant inhibitory effect on an avirulent strain of Mycobacterium tubercluosis (H37Ra) at the initial screening doses (125 and 6.25 mu g/ml). These were bark and leaf extracts of Khaya senegalensis and the leaf extract of Rosmarinus officinalis L. Further fractions of these plant extracts were prepared with n-hexane, chloroform, ethyl acetate, n-butanol, ethanol and water, and the activity of these extracts was retained in hydrophobic fractions. Cytotoxicity assays revealed that the chloroform fraction of Khaya senegalensis bark was non-toxic to human monocyte-derived macrophages and other cell types at the concentrations used and hence, further analysis, including assessment of IC50 and intracellular activity was done with this fraction. Conclusion: These results encourage further investigations to identify the active compound(s) within the chloroform fraction of Khaya senegalensis bark. (C) 2014 Elsevier Ireland Ltd. All rights reserved.

    Place, publisher, year, edition, pages
    Elsevier, 2014
    Keywords
    Mycobacterium tuberculosis; Sudanese medicinal plants; Primary human macrophages; Luminescence reporter assay; Cytotoxicity assay
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-113785 (URN)10.1016/j.jep.2014.09.020 (DOI)000347022700016 ()25261689 (PubMedID)
    Note

    Funding Agencies|Ekhaga Foundation [2011-33]; Swedish Insitute

    Available from: 2015-02-02 Created: 2015-01-30 Last updated: 2019-01-07
  • 44.
    Kalsum, Sadaf
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Braian, Clara
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Koeken, Valerie A. C. M.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Radboud University of Nijmegen, Netherlands.
    Raffetseder, Johanna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Lindroth, Margaretha
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    van Crevel, Reinout
    Radboud University of Nijmegen, Netherlands.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    The Cording Phenotype of Mycobacterium tuberculosis Induces the Formation of Extracellular Traps in Human Macrophages2017In: Frontiers in Cellular and Infection Microbiology, E-ISSN 2235-2988, Vol. 7, article id 278Article in journal (Refereed)
    Abstract [en]

    The causative agent of tuberculosis, Mycobacterium tuberculosis, shares several characteristics with organisms that produce biofilms during infections. One of these is the ability to form tight bundles also known as cords. However, little is known of the physiological relevance of the cording phenotype. In this study, we investigated whether cord-forming M. tuberculosis induce the formation of macrophage extracellular traps (METs) in human monocyte-derived macrophages. Macrophages have previously been shown to produce extracellular traps in response to various stimuli. We optimized bacterial culturing conditions that favored the formation of the cord-forming phenotype as verified by scanning electron microscopy. Microscopy analysis of METs formation during experimental infection of macrophages with M. tuberculosis revealed that cord-forming M. tuberculosis induced significantly more METs compared to the non-cording phenotype. Deletion of early secreted antigenic target-6 which is an important virulence factor of M. tuberculosis, abrogated the ability of the bacteria to induce METs. The release of extracellular DNA from host cells during infection may represent a defense mechanism against pathogens that are difficult to internalize, including cord-forming M. tuberculosis.

  • 45.
    Kesik-Brodacka, Malgorzata
    et al.
    Institute Biotechnol and Antibiot, Poland.
    Lipiec, Agnieszka
    Warsaw University of Life Science, Poland.
    Kozak Ljunggren, Monika
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Polish Academic Science, Poland.
    Jedlina, Luiza
    Polish Academic Science, Poland.
    Miedzinska, Katarzyna
    Polish Academic Science, Poland; Queens Medical Research Institute, Scotland.
    Mikolajczak, Magdalena
    Polish Academic Science, Poland.
    Plucienniczak, Andrzej
    Institute Biotechnol and Antibiot, Poland.
    Legocki, Andrzej B.
    Polish Academic Science, Poland.
    Wedrychowicz, Halina
    Polish Academic Science, Poland.
    Immune response of rats vaccinated orally with various plant-expressed recombinant cysteine proteinase constructs when challenged with Fasciola hepatica metacercariae2017In: PLoS Neglected Tropical Diseases, ISSN 1935-2727, E-ISSN 1935-2735, Vol. 11, no 3Article in journal (Refereed)
    Abstract [en]

    Background Cysteine proteinases of Fasciola hepatica are important candidates for vaccine antigens because of their role in fluke biology and host-parasite relationships. In our previous experiments, we found that a recombinant cysteine proteinase cloned from adult F. hepatica ( CPFhW) can protect rats against liver fluke infections when it is administered intramuscularly or intranasally in the form of cDNA. We also observed considerable protection upon challenge following mucosal vaccination with inclusion bodies containing recombinant CPFhW produced in Escherichia coli. In this study, we explore oral vaccination, which may be the desired method of delivery and is potentially capable of preventing infections at the site of helminth entry. To provide antigen encapsulation and to protect the vaccine antigen from degradation in the intestinal tract, transgenic plant-based systems are used. Methodology Conclusions We obtained substantial protection after oral administration of the plant-produced hybrids of CPFhW and HBcAg. The highest level of protection (65.4%)was observed in animals immunised with transgenic plants expressing the mature CPFhW enzyme flanked by Gly-rich linkers and inserted into c/e1 epitope of truncated HBcAg. The immunised rats showed clear IgG1 and IgM responsesIn the present study, we aimed to evaluate the protective ability of mucosal vaccinations of 12-week- old rats with CPFhW produced in a transgenic-plant-based system. To avoid inducing tolerance and to maximise the immune response induced by oral immunisation, we used the hepatitis B virus (HBV) core protein ( HBcAg) as a carrier. Animals were immunised with two doses of the antigen and challenged with 25 or 30 metacercariae of F. hepatica. Conclusions We obtained substantial protection after oral administration of the plant-produced hybrids of CPFhW and HBcAg. The highest level of protection (65.4%) was observed in animals immunised with transgenic plants expressing the mature CPFhW enzyme flanked by Gly- rich linkers and inserted into c/e1 epitope of truncated HBcAg. The immunised rats showed clear IgG1 and IgM responses to CPFhW for 4 consecutive weeks after the challenge.

  • 46.
    Kiedrowski, Megan R.
    et al.
    Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Crosby, Heidi A.
    Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Hernandez, Frank J
    Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Malone, Cheryl L.
    Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    McNamara II, James O.
    Department of Internal Medicine, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Horswill, Alexander R.
    Department of Microbiology, Roy J. and Lucille A. Carver College of Medicine, University of of Iowa, Iowa City, IA, United States.
    Staphylococcus aureus Nuc2 is a functional, surface-attached extracellular nuclease2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 4, article id e95574Article in journal (Refereed)
    Abstract [en]

    Staphylococcus aureus is a prominent bacterial pathogen that causes a diverse range of acute and chronic infections. Recently, it has been demonstrated that the secreted nuclease (Nuc) enzyme is a virulence factor in multiple models of infection, and in vivo expression of nuc has facilitated the development of an infection imaging approach based on Nuc-activatable probes. Interestingly, S. aureus strains encode a second nuclease (Nuc2) that has received limited attention. With the growing interest in bacterial nucleases, we sought to characterize Nuc2 in more detail through localization, expression, and biochemical studies. Fluorescence microscopy and alkaline phosphatase localization approaches using Nuc2-GFP and Nuc2-PhoA fusions, respectively, demonstrated that Nuc2 is membrane bound with the C-terminus facing the extracellular environment, indicating it is a signal-anchored Type II membrane protein. Nuc2 enzyme activity was detectable on the S. aureus cell surface using a fluorescence resonance energy transfer (FRET) assay, and in time courses, both nuc2 transcription and enzyme activity peaked in early logarithmic growth and declined in stationary phase. Using a mouse model of S. aureus pyomyositis, Nuc2 activity was detected with activatable probes in vivo in nuc mutant strains, demonstrating that Nuc2 is produced during infections. To assess Nuc2 biochemical properties, the protein was purified and found to cleave both single- and double-stranded DNA, and it exhibited thermostability and calcium dependence, paralleling the properties of Nuc. Purified Nuc2 prevented biofilm formation in vitro and modestly decreased biomass in dispersal experiments. Altogether, our findings confirm that S. aureus encodes a second, surface-attached and functional DNase that is expressed during infections and displays similar biochemical properties to the secreted Nuc enzyme. © 2014 Kiedrowski et al.

  • 47.
    Kindberg, Elin
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology . Linköping University, Faculty of Health Sciences.
    Host genetic risk factors to viral diseases - a double-edged sword: Studies of norovirus and tick-borne encephalitis virus2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    It is today well known that the outcome of a certain infection depends on factors of both the host and the pathogen. Studies of host genetic susceptibility to infectious diseases aim to increase the understanding of why some individuals are more susceptible than others, to a certain infection. Knowledge of genetic susceptibility to a viral disease may be used in development of new therapeutic means, and also to recognize individuals who are at increased risk of severe symptoms if infected with a pathogen. It seems however that a risk factor for one disease may play a protective role in another situation; like a double-edged sword.

    In this thesis I have studied genetic factors affecting susceptibility to norovirus (NoV) and factors affecting the risk of developing tick-borne encephalitis (TBE) after infection with TBE virus (TBEV). NoV is the cause of the “winter vomiting disease”, affecting millions of people every year, and causing up to 200,000 fatalities among children in developing countries, each year. It is today recognized that the secretor status of an individual, i.e. the ability to express ABO blood groups and related antigens, in secretions and on mucosa, affect the risk of being infected by NoV. By studying authentic NoV outbreaks in Denmark, Spain and Sweden and by comparing the secretor status of affected and unaffected individuals we were able to confirm that secretor status have indeed great impact on susceptibility to some NoV strains, but also that there are strains circulating, which infect individuals regardless of secretor status.

    TBEV is endemic in many parts of Europe and Asia but studies have shown that 70-95% of all infections are asymptomatic or sub-clinical. Some individuals do however develop TBE, a severe disease including meningitis or encephalitis with or without myelitis. Also, many patients suffer from long-time sequelae and TBEV infections may in worst case be fatal. The reason for difference in disease outcome is not known and we have chosen to study if genetic factors affecting the immune response may play a role in disease outcome. To do this we used a prospectively collected Lithuanian material with samples from patients with TBE, AME (aseptic meningoencephalitis) and matched healthy controls. So far we have found that a deletion in chemokine receptor 5 (CCR5), a gene encoding a receptor involved in cell migration, is a risk factor for developing disease. We have also data showing that toll-like receptor 3 (TLR3), a receptor recognizing double stranded RNA (dsRNA), which is a product of TBEV replication, may instead of being protective increase the risk of TBE.

    List of papers
    1. Host genetic resistance to symptomatic norovirus (GGII.4) infections in Denmark
    Open this publication in new window or tab >>Host genetic resistance to symptomatic norovirus (GGII.4) infections in Denmark
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    2007 (English)In: Journal of Clinical Microbiology, ISSN 0095-1137, E-ISSN 1098-660X, Vol. 45, no 8, p. 2720-2722Article in journal (Refereed) Published
    Abstract [en]

    A total of 61 individuals involved in five norovirus outbreaks in Denmark were genotyped at nucleotides 428 and 571 of the FUT2 gene, determining secretor status, i.e., the presence of ABH antigens in secretions and on mucosa. A strong correlation (P = 0.003) was found between the secretor phenotype and symptomatic disease, extending previous knowledge and confirming that nonsense mutations in the FUT2 gene provide protection against symptomatic norovirus (GGII.4) infections. Copyright © 2007, American Society for Microbiology. All Rights Reserved.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-40699 (URN)10.1128/JCM.00162-07 (DOI)53918 (Local ID)53918 (Archive number)53918 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-12-13
    2. The G428A nonsense mutation in FUT2 provides strong but not absolute protection against symptomatic GII.4 Norovirus infection.
    Open this publication in new window or tab >>The G428A nonsense mutation in FUT2 provides strong but not absolute protection against symptomatic GII.4 Norovirus infection.
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    2009 (English)In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 4, no 5, p. e5593-Article in journal (Refereed) Published
    Abstract [en]

    In November 2004, 116 individuals in an elderly nursing home in El Grao de Castellón, Spain were symptomatically infected with genogroup II.4 (GII.4) norovirus. The global attack rate was 54.2%. Genotyping of 34 symptomatic individuals regarding the FUT2 gene revealed that one patient was, surprisingly, a non-secretor, hence indicating secretor-independent infection. Lewis genotyping revealed that Lewis-positive and negative individuals were susceptible to symptomatic norovirus infection indicating that Lewis status did not predict susceptibility. Saliva based ELISA assays were used to determine binding of the outbreak virus to saliva samples. Saliva from a secretor-negative individual bound the authentic outbreak GII.4 Valencia/2004/Es virus, but did not in contrast to secretor-positive saliva bind VLP of other strains including the GII.4 Dijon strain. Amino acid comparison of antigenic A and B sites located on the external loops of the P2 domain revealed distinct differences between the Valencia/2004/Es and Dijon strains. All three aa in each antigenic site as well as 10/11 recently identified evolutionary hot spots, were unique in the Valencia/2004/Es strain compared to the Dijon strain. To the best of our knowledge, this is the first example of symptomatic GII.4 norovirus infection of a Le(a+b-) individual homozygous for the G428A nonsense mutation in FUT2. Taken together, our study provides new insights into the host genetic susceptibility to norovirus infections and evolution of the globally dominating GII.4 viruses.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-18974 (URN)10.1371/journal.pone.0005593 (DOI)19440360 (PubMedID)
    Note
    Original Publication: Beatrice Carlsson, Elin Kindberg, Javier Buesa, Gustaf E Rydell, Marta Fos Lidón, Rebeca Montava, Reem Abu Mallouh, Ammi Grahn, Jesús Rodríguez-Díaz, Juan Bellido, Alberto Arnedo, Göran Larson and Lennart Svensson, The G428A nonsense mutation in FUT2 provides strong but not absolute protection against symptomatic GII.4 Norovirus infection., 2009, PLoS ONE, (4), 5, e5593. http://dx.doi.org/10.1371/journal.pone.0005593 Licensed under Creative CommonsAvailable from: 2009-06-10 Created: 2009-06-07 Last updated: 2017-12-13Bibliographically approved
    3. Norovirus Gastroenteritis Outbreak with a Secretor-independent Susceptibility Pattern, Sweden
    Open this publication in new window or tab >>Norovirus Gastroenteritis Outbreak with a Secretor-independent Susceptibility Pattern, Sweden
    2010 (English)In: Emerging Infectious Diseases, ISSN 1080-6040, E-ISSN 1080-6059, Vol. 16, no 1, p. 81-87Article in journal (Refereed) Published
    Abstract [en]

    Norovirus (NoV) is recognized as the commonest cause of acute gastroenteritis among adults. Susceptibility to disease has been associated with histo-blood group antigens and secretor status; nonsecretors are almost completely resistant to disease. We report a foodborne outbreak of GI.3 NoV gastroenteritis that affected 33/83 (40%) persons. Symptomatic disease was as likely to develop in nonsecretors as in secretors (odds ratio [OR] 1.41, 95% confidence interval [CI] 0.46-4.36 vs. OR 0.71, 95% Cl 0.23-2.18, p = 0.57). Moreover, no statistical difference in susceptibility was found between persons of different Lewis or ABO phenotypes. The capsid gene of the outbreak strain shares high amino acid homology with the Kashiwa645 GI.3 strain, previously shown to recognize nonsecretor saliva, as well as synthetic Lewis a. This norovirus outbreak affected persons regardless of secretor status or Lewis or ABO phenotypes.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-53443 (URN)10.3201/eid1601.090633 (DOI)
    Note
    Original Publication: Johan Nordgren, Per-Eric Lindgren, Andreas Matussek and Lennart Svensson, Norovirus Gastroenteritis Outbreak with a Secretor-independent Susceptibility Pattern, Sweden, 2010, EMERGING INFECTIOUS DISEASES, (16), 1, 81-87. http://dx.doi.org/10.3201/eid1601.090633 Licensee: National Center for Infectious Diseases http://www.cdc.gov/ncidod/eid/index.htm Available from: 2010-01-22 Created: 2010-01-22 Last updated: 2017-12-12
    4. A deletion in the chemokine receptor 5 (CCR5) gene is associated with tickborne encephalitis
    Open this publication in new window or tab >>A deletion in the chemokine receptor 5 (CCR5) gene is associated with tickborne encephalitis
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    2008 (English)In: Journal of Infectious Diseases, ISSN 0022-1899, E-ISSN 1537-6613, Vol. 197, no 2, p. 266-269Article in journal (Refereed) Published
    Abstract [en]

    Tickborne encephalitis (TBE) virus infections can be asymptomatic or cause moderate to severe injuries of the central nervous system. Why some individuals develop severe disease is unknown, but a role for host genetic factors has been suggested. To investigate whether chemokine receptor CCR5 is associated with TBE, CCR5Δ32 genotyping was performed among Lithuanian patients with TBE (n = 129) or with aseptic meningoencephalitis (n = 76) as well as among control subjects (n = 134). We found individuals homozygous for CCR5Δ32 (P = .026) only among patients with TBE and a higher allele prevalence among patients with TBE compared with the other groups studied. CCR5Δ32 allele prevalence also increased with the clinical severity of disease. © 2007 by the Infectious Diseases Society of America. All rights reserved.

    Keywords
    Alleles Encephalitis, Tick-Borne/epidemiology/*genetics/physiopathology *Gene Deletion Gene Frequency *Genetic Predisposition to Disease Homozygote Humans Lithuania/epidemiology Meningoencephalitis/genetics Receptors, CCR5/*genetics Severity of Illness In
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-43369 (URN)10.1086/524709 (DOI)73655 (Local ID)73655 (Archive number)73655 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2017-12-13Bibliographically approved
    5. A Missense Mutation in the Toll‐like Receptor 3 Gene (TLR3) is Associated with Decreased Risk of Tick‐borne Encephalitis
    Open this publication in new window or tab >>A Missense Mutation in the Toll‐like Receptor 3 Gene (TLR3) is Associated with Decreased Risk of Tick‐borne Encephalitis
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    (English)Manuscript (preprint) (Other (popular science, discussion, etc.))
    Abstract [en]

    Infections with tick‐borne encephalitis virus (TBEV) may be asymptomatic or cause severe symptoms from the central nervous system, such as meningitis or encephalitis. A mutation in the chemokine receptor 5 (CCR5) gene has been associated with increased risk of TBE but can only explain a limited number of cases and investigations of further risk factors are clearly needed. To investigate the importance of the innate immune response, 128 Lithuanian TBE patients with meningitis or encephalitis, 77 patients with aseptic meningoencephalitis (AME) and 135 healthy controls were analyzed for three mutations: two in the toll‐like receptor 3 (TLR3) gene and one in the 2´‐5´ oligoadenylate synthetase 1 (OAS1) gene. While no association was found between the mutation in OAS1 and TBE, the genotype distribution of one of the mutations in TLR3, rs3775291, differed significantly between the TBE patients and the controls. 61%, 32% and 7% of the TBE patients (n=127) were carriers of the wild‐type/wild‐type, heterozygous and mutant/mutant genotype of TLR3 rs3775291 genotype respectively. The corresponding percentages for healthy controls (n=126) were 52%, 29% and 19% (P=0.02) and for AME patients (n=75) 47%, 32% and 21% (P=0.009). The wild‐type rs3775291 allele was more common among TBE patients than healthy controls (allele frequency 0.768 vs. 0.663, P=0.01), suggesting that functional TLR3 is a risk factor for severe TBEV infection.

    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-55017 (URN)
    Available from: 2010-04-27 Created: 2010-04-27 Last updated: 2018-10-08
  • 48.
    Kindberg, Elin
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Svensson, Lennart
    Linköping University, Department of Clinical and Experimental Medicine, Molecular Virology. Linköping University, Faculty of Health Sciences.
    Genetic basis of host resistance to norovirus infection2009In: FUTURE VIROLOGY, ISSN 1746-0794, Vol. 4, no 4, p. 369-382Article, review/survey (Refereed)
    Abstract [en]

    Noroviruses have emerged as a major cause of acute gastroenteritis in humans of all ages and are responsible for 200,000 deaths every year, mainly in developing countries. Despite high infectivity and lack of long-term immunity, authentic and volunteer studies have shown existence of inherited protective factors. Recent studies have shown that secretor status controlled by the alpha(1,2)-fucosyltransferase gene located on chromosome 19 determines susceptibility to most, if not all, norovirus infections, with individuals homozygous for the G428A nonsense mutation (nonsecretors) representing 20% of the highly protected European population.

  • 49.
    Kiwanuka, Elizabeth
    et al.
    Brown University, RI 02903 USA.
    Junker, Johan
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Disaster Medicine and Traumatology.
    Eriksson, Elof
    Harvard Medical Sch, MA USA.
    Transforming growth factor beta 1 regulates the expression of CCN2 in human keratinocytes via Smad-ERK signalling2017In: International Wound Journal, ISSN 1742-4801, E-ISSN 1742-481X, Vol. 14, no 6, p. 1006-1018Article in journal (Refereed)
    Abstract [en]

    Connective tissue growth factor (CCN2/CTGF) and transforming growth factor 1 (TGF-1) are important regulators of skin wound healing, but controversy remains regarding their expression in epithelial cell lineages. Here, we investigate the expression of CCN2 in keratinocytes during reepithelialisation and its regulation by TGF-1. CCN2 was detected in the epidermis of healing full-thickness porcine wounds. Human keratinocytes were incubated with or without 10 ng/ml TGF-1, and signalling pathways were blocked with 10-M SIS3 or 20-M PD98059. Semi-quantitative real-time PCR was used to study CCN2 mRNA expression, and western blot was used to measure CCN2, phosphorylated-ERK1/2, ERK1/2, phosphorylated-Smad3 and Smad2/3 proteins. CCN2 was transiently expressed in neoepidermis at the leading edge of the wound in vivo. In vitro, CCN2 expression was induced by TGF-1 at 2 hours (7amp;lt;boldamp;gt;amp;lt;/boldamp;gt;5 +/- 1amp;lt;boldamp;gt;amp;lt;/boldamp;gt;9-fold mRNA increase and 3amp;lt;boldamp;gt;amp;lt;/boldamp;gt;0 +/- 0amp;lt;boldamp;gt;amp;lt;/boldamp;gt;6-fold protein increase) and 12 hours (5amp;lt;boldamp;gt;amp;lt;/boldamp;gt;4 +/- 1amp;lt;boldamp;gt;amp;lt;/boldamp;gt;9-fold mRNA increase and 3amp;lt;boldamp;gt;amp;lt;/boldamp;gt;3 +/- 0amp;lt;boldamp;gt;amp;lt;/boldamp;gt;6-fold protein increase). Compared with inhibiting the SMAD pathway, inhibiting the mitogen-activated protein kinase (MAPK) pathway was more effective in reducing TGF-1-induced CCN2 mRNA and protein expression. Inhibition of the MAPK pathway had minimal impact on the activity of the SMAD pathway. CCN2 is expressed in keratinocytes in response to tissue injury or TGF-1. In addition, TGF-1 induces CCN2 expression in keratinocytes through the ras/MEK/ERK pathway. A complete understanding of CCN2 expression in keratinocytes is critical to developing novel therapies for wound healing and cutaneous malignancy.

  • 50.
    Kumar, Arun
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. GSK, Italy.
    Meldgaard, Trine Sundebo
    GSK, Italy; Tech Univ Denmark, Denmark.
    Bertholet, Sylvie
    GSK, Italy; GSK, MD 20850 USA.
    Novel Platforms for the Development of a Universal influenza vaccine2018In: Frontiers in Immunology, ISSN 1664-3224, E-ISSN 1664-3224, Vol. 9, article id 600Article, review/survey (Refereed)
    Abstract [en]

    Despite advancements in immunotherapeutic approaches, influenza continues to cause severe illness, particularly among immunocompromised individuals, young children, and elderly adults. Vaccination is the most effective way to reduce rates of morbidity and mortality caused by influenza viruses. Frequent genetic shift and drift among influenzavirus strains with the resultant disparity between circulating and vaccine virus strains limits the effectiveness of the available conventional influenza vaccines. One approach to overcome this limitation is to develop a universal influenza vaccine that could provide protection against all subtypes of influenza viruses. Moreover, the development of a novel or improved universal influenza vaccines may be greatly facilitated by new technologies including virus-like particles, T-cell-inducing peptides and recombinant proteins, synthetic viruses, broadly neutralizing antibodies, and nucleic acid-based vaccines. This review discusses recent scientific advances in the development of next-generation universal influenza vaccines.

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