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  • 1.
    Abate Waktola, Ebba Abate
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. EPHI, Ethiopia.
    Blomgran, Robert
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Verma, Deepti
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Fredrikson, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Belayneh, Meseret
    Univ Addis Abeba, Ethiopia.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Clinical genetics.
    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, Kalmar, Sweden.
    Polymorphisms in CARD8 and NLRP3 are associated with extrapulmonary TB and poor clinical outcome in active TB in Ethiopia2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, article id 3126Article in journal (Refereed)
    Abstract [en]

    Innate immunity is a first line defense against Mycobacterium tuberculosis infection where inflammasome activation and secretion of the pro-inflammatory cytokine IL-1beta, plays a major role. Thus, genetic polymorphisms in innate immunity-related genes such as CARD8 and NLRP3 may contribute to the understanding of why most exposed individuals do not develop infection. Our aim was to investigate the association between polymorphisms in CARD8 and NLRP3 and active tuberculosis (TB) as well as their relationship to treatment outcome in a high-endemic setting for TB. Polymorphisms in CARD8 (C10X) and NLRP3 (Q705K) were analysed in 1190 TB patients and 1990 healthy donors (HD). There was a significant association between homozygotes in the CARD8 polymorphism and extrapulmonary TB (EPTB), which was not the case for pulmonary TB or HDs. Among TB-patients, there was an association between poor treatment outcome and the NLRP3 (Q705K) polymorphism. Our study shows that inflammasome polymorphisms are associated with EPTB and poor clinical outcome in active TB in Ethiopia. The practical implications and determining causal relationships on a mechanistic level needs further study.

  • 2.
    Abuzeid, Nadir
    et al.
    Medical and Aromat Plants Research Institute, Sudan; Omdurman Islamic University, Sudan.
    Kalsum, Sadaf
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Koshy, Richin John
    Larsson, Marie C
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Glader, Mikaela
    Andersson, Henrik
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Raffetseder, Johanna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Pienaar, Elsje
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Eklund, Daniel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Alhassan, Muddathir S.
    Medical and Aromat Plants Research Institute, Sudan.
    AlGadir, Haidar A.
    Medical and Aromat Plants Research Institute, Sudan.
    Koko, Waleed S.
    Medical and Aromat Plants Research Institute, Sudan.
    Schon, Thomas
    Kalmar County Hospital, Sweden.
    Ahmed Mesaik, M.
    University of Kebangsaan Malaysia, Malaysia; University of Karachi, Pakistan.
    Abdalla, Omer M.
    University of Karachi, Pakistan.
    Khalid, Asaad
    Medical and Aromat Plants Research Institute, Sudan.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Antimycobacterial activity of selected medicinal plants traditionally used in Sudan to treat infectious diseases2014In: Journal of Ethnopharmacology, ISSN 0378-8741, E-ISSN 1872-7573, Vol. 157, p. 134-139Article in journal (Refereed)
    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.

  • 3.
    Andersson, Henrik
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Eklund, Daniel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Ngoh, Eyler
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Persson, Alexander
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Andersson, Blanka
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Svensson, Kristoffer
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Blomgran, Robert
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Apoptotic neutrophils augment the inflammatory response to Mycobacterium tuberculosis infection in human macrophages2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 7, p. e101514-Article in journal (Refereed)
    Abstract [en]

    Macrophages in the lung are the primary cells being infected by Mycobacterium tuberculosis (Mtb) during tuberculosis. Innate immune cells such as macrophages and neutrophils are first recruited to the site of infection, and mount the early immune protection against this intracellular pathogen. Neutrophils are short-lived cells and removal of apoptotic cells by resident macrophages is a key event in the resolution of inflammation and tissue repair. Such anti-inflammatory activity is not compatible with effective immunity to intracellular pathogens. We therefore investigated how uptake of apoptotic neutrophils by Mtb-activated human monocyte-derived macrophages modulates their function. We show that Mtb infection exerts a potent pro-inflammatory activation of human macrophages with enhanced gene activation and release of several cytokines (TNF, IL-1ß, IL-6, IL-18 and IL-10). This response was augmented by apoptotic neutrophils. Macrophages containing both Mtb and apoptotic cells showed a stronger cytokine expression than non-infected cells. The enhanced macrophage response is linked to apoptotic neutrophil-driven activation of the NLRP3 inflammasome and subsequent IL-1β signalling. We also demonstrate that apoptotic neutrophils not only modulate the inflammatory response, but also enhance the capacity of infected macrophages to control intracellular growth of virulent Mtb. Taken together, these results suggest a novel role for apoptotic neutrophils in the modulation of the macrophage-dependent inflammatory response, which can contribute to the early control of Mtb infection.

  • 4.
    Blomgran, Robert
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Brodin Patcha, Veronika
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Verma, Deepti
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Bergström, Ida
    Linköping University, Department of Medical and Health Sciences, Cardiology. Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Sjöwall, Christoffer
    Linköping University, Department of Clinical and Experimental Medicine, Rheumatology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Rheumatology in Östergötland.
    Eriksson, Per
    Linköping University, Department of Clinical and Experimental Medicine, Rheumatology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Heart and Medicine Centre, Department of Nephrology UHL.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Sarndahl, Eva
    University of Örebro.
    Common Genetic Variations in the NALP3 Inflammasome Are Associated with Delayed Apoptosis of Human Neutrophils2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 3Article in journal (Refereed)
    Abstract [en]

    Background: Neutrophils are key-players in the innate host defense and their programmed cell death and removal are essential for efficient resolution of inflammation. These cells recognize a variety of pathogens, and the NOD-like receptors (NLRs) have been suggested as intracellular sensors of microbial components and cell injury/stress. Some NLR will upon activation form multi-protein complexes termed inflammasomes that result in IL-1 beta production. NLR mutations are associated with auto-inflammatory syndromes, and our previous data propose NLRP3 (Q705K)/CARD-8 (C10X) polymorphisms to contribute to increased risk and severity of inflammatory disease by acting as genetic susceptibility factors. These gene products are components of the NALP3 inflammasome, and approximately 6.5% of the Swedish population are heterozygote carriers of these combined gene variants. Since patients carrying the Q705K/C10X polymorphisms display leukocytosis, the aim of the present study was to find out whether the inflammatory phenotype was related to dysfunctional apoptosis and impaired clearance of neutrophils by macrophages. less thanbrgreater than less thanbrgreater thanMethods and Findings: Patients carrying the Q705K/C10X polymorphisms displayed significantly delayed spontaneous as well as microbe-induced apoptosis compared to matched controls. Western blotting revealed increased levels and phosphorylation of Akt and Mcl-1 in the patients neutrophils. In contrast to macrophages from healthy controls, macrophages from the patients produced lower amounts of TNF; suggesting impaired macrophage clearance response. less thanbrgreater than less thanbrgreater thanConclusions: The Q705K/C10X polymorphisms are associated with delayed apoptosis of neutrophils. These findings are explained by altered involvement of different regulators of apoptosis, resulting in an anti-apoptotic profile. Moreover, the macrophage response to ingestion of microbe-induced apoptotic neutrophils is altered in the patients. Taken together, the patients display impaired turnover and clearance of apoptotic neutrophils, pointing towards a dysregulated innate immune response that influences the resolution of inflammation. The future challenge is to understand how microbes affect the activation of inflammasomes, and why this interaction will develop into severe inflammatory disease in certain individuals.

  • 5.
    Braian, Clara
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Svensson, Mattias
    Karolinska Institute, Sweden.
    Brighenti, Susanna
    Karolinska Institute, Sweden.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Parasa, Venkata R.
    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.
    A 3D Human Lung Tissue Model for Functional Studies on Mycobacterium tuberculosis Infection2015In: Journal of Visualized Experiments, ISSN 1940-087X, E-ISSN 1940-087X, no 104, p. 1-9, article id e53084Article in journal (Refereed)
    Abstract [en]

    Tuberculosis (TB) still holds a major threat to the health of people worldwide, and there is a need for cost-efficient but reliable models to help us understand the disease mechanisms and advance the discoveries of new treatment options. In vitro cell cultures of monolayers or co-cultures lack the three-dimensional (3D) environment and tissue responses. Herein, we describe an innovative in vitro model of a human lung tissue, which holds promise to be an effective tool for studying the complex events that occur during infection with Mycobacterium tuberculosis (M. tuberculosis). The 3D tissue model consists of tissue-specific epithelial cells and fibroblasts, which are cultured in a matrix of collagen on top of a porous membrane. Upon air exposure, the epithelial cells stratify and secrete mucus at the apical side. By introducing human primary macrophages infected with M. tuberculosis to the tissue model, we have shown that immune cells migrate into the infected-tissue and form early stages of TB granuloma. These structures recapitulate the distinct feature of human TB, the granuloma, which is fundamentally different or not commonly observed in widely used experimental animal models. This organotypic culture method enables the 3D visualization and robust quantitative analysis that provides pivotal information on spatial and temporal features of host cell-pathogen interactions. Taken together, the lung tissue model provides a physiologically relevant tissue micro-environment for studies on TB. Thus, the lung tissue model has potential implications for both basic mechanistic and applied studies. Importantly, the model allows addition or manipulation of individual cell types, which thereby widens its use for modelling a variety of infectious diseases that affect the lungs.

  • 6.
    Brighenti, S.
    et al.
    Karolinska Inst, Sweden.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Toward the understanding of human tuberculosis2018In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 284, no 2, p. 113-115Article in journal (Other academic)
    Abstract [en]

    n/a

  • 7.
    Brighenti, Susanna
    et al.
    Center for Infectious Medicine, Huddinge Hospital Karolinska Institute.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    How Mycobacterium tuberculosis Manipulates Innate and Adaptive Immunity: New Views of an Old Topic2012In: Understanding Tuberculosis: Analyzing the Origin of Mycobacterium Tuberculosis Pathogenicity / [ed] Pere-Joan Cardona, InTech Open , 2012, p. 207-234Chapter in book (Other academic)
    Abstract [en]

    Mycobacterium tuberculosis in an attempt to understand the extent to which the bacilli has adapted itself to the host and to its final target. On the other hand, there is a section in which other specialists discuss how to manipulate this immune response to obtain innovative prophylactic and therapeutic approaches to truncate the intimal co-evolution between Mycobacterium tuberculosis and the Homo sapiens.

  • 8.
    Das, Jyotirmoy
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences.
    Verma, Deepti
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Medicine and Health Sciences.
    Gustafsson, Mika
    Linköping University, Department of Physics, Chemistry and Biology, Bioinformatics. Linköping University, Faculty of Science & Engineering.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology, Infection and Inflammation. Linköping University, Faculty of Medicine and Health Sciences.
    Identification of DNA methylation patterns predisposing for an efficient response to BCG vaccination in healthy BCG-naive subjects2019In: Epigenetics, ISSN 1559-2294, E-ISSN 1559-2308, Vol. 14, no 6, p. 589-601Article in journal (Refereed)
    Abstract [en]

    The protection against tuberculosis induced by the Bacille Calmette Guerin (BCG) vaccine is unpredictable. In our previous study, altered DNA methylation pattern in peripheral blood mononuclear cells (PBMCs) in response to BCG was observed in a subgroup of individuals, whose macrophages killed mycobacteria effectively (responders). These macrophages also showed production of Interleukin-1 beta (IL-1 beta) in response to mycobacterial stimuli before vaccination. Here, we hypothesized that the propensity to respond to the BCG vaccine is reflected in the DNA methylome. We mapped the differentially methylated genes (DMGs) in PBMCs isolated from responders/non-responders at the time point before vaccination aiming to identify possible predictors of BCG responsiveness. We identified 43 DMGs and subsequent bioinformatic analyses showed that these were enriched for actin-modulating pathways, predicting differences in phagocytosis. This could be validated by experiments showing that phagocytosis of mycobacteria, which is an event preceding mycobacteria-induced IL-1 beta production, was strongly correlated with the DMG pattern.

  • 9.
    Ederth, Thomas
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Molecular Physics. Linköping University, Faculty of Science & Engineering.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Orihuela, Beatriz
    Duke Univ, NC 28516 USA.
    Rittschof, Daniel
    Duke Univ, NC 28516 USA.
    Resistance of Zwitterionic Peptide Monolayers to Biofouling2019In: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 35, no 5, p. 1818-1827Article in journal (Refereed)
    Abstract [en]

    Self-assembled monolayers (SAMs) are widely used in science and engineering, and recent progress has demonstrated the utility of zwitterionic peptides with alternating lysine (K) and glutamic acid (E) residues for antifouling purposes. Aiming at developing a peptide-based fouling-resistant SAM suitable for presentation of surface-attached pheromones for barnacle larvae, we have investigated five different peptide SAMs, where four are based on the EK motif, and the fifth was designed based on general principles for fouling resistance. The SAMs were formed by self-assembly onto gold substrates via cysteine residues on the peptides, and formation of SAMs was verified via ellipsometry, wettability, infrared reflection-absorption spectroscopy and cyclic voltammetry. Settlement of cypris larvae of the barnacle Balanus (=Amphibalanus) amphitrite, the target of pheromone studies, was tested. SAMs were also subjected to fouling assays using protein solutions, blood serum, and the bacterium Mycobacterium marinum. The results confirm the favorable antifouling properties of EK-containing peptides in most of the assays, although this did not apply to the barnacle larvae settlement test, where settlement was low on only one of the peptide SAMs. The one peptide that had antifouling properties for barnacles did not contain a pheromone motif, and would not be susceptible to degredation by common serine proteases. We conclude that the otherwise broadly effective antifouling properties of EK-containing peptide SAMs is not directly applicable to barnacles, and that great care must be exercised in the design of peptide-based SAMs for presentation of barnacle-specific ligands.

  • 10.
    Eklund, Daniel
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Persson, Hans Lennart
    Linköping University, Department of Medical and Health Sciences, Pulmonary Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Respiratory Medicine.
    Larsson, Marie C.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology. Linköping University, Faculty of Health Sciences.
    Welin, Amanda
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Idh, Jonna
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Paues, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Fransson, Sven-Göran
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Radiology in Linköping.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Vitamin D enhances IL-1β secretion and restricts growth of Mycobacterium tuberculosis in macrophages from TB patients2013In: International Journal of Mycobacteriology, ISSN 2212-5531, Vol. 2, no 1, p. 18-25Article in journal (Refereed)
    Abstract [en]

    The emergence of multidrug-resistant strains of Mycobacterium tuberculosis (MTB), the bacterium responsible for tuberculosis (TB), has rekindled the interest in the role of nutritional supplementation of micronutrients, such as vitamin D, as adjuvant treatment. Here, the growth of virulent MTB in macrophages obtained from the peripheral blood of patients with and without TB was studied. The H37Rv strain genetically modified to express Vibrio harveyi luciferase was used to determine the growth of MTB by luminometry in the human monocyte-derived macrophages (hMDMs) from study subjects. Determination of cytokine levels in culture supernatants was performed using a flow cytometry-based bead array technique. No differences in intracellular growth of MTB were observed between the different study groups. However, stimulation with 100 nM 1,25-dihydroxyvitamin D significantly enhanced the capacity of hMDMs isolated from TB patients to control the infection. This effect was not observed in hMDMs from the other groups. The interleukin (IL)-1β and IL-10 release by hMDMs was clearly increased upon stimulation with 1,25-dihydroxyvitamin D. Furthermore, the 1,25-dihydroxyvitamin D stimulation also led to elevated levels of TNF-α (tumor necrosis factor-alpha) and IL-12p40. It was concluded that vitamin D triggers an inflammatory response in human macrophages with enhanced secretion of cytokines, as well as enhancing the capacity of hMDMs from patients with active TB to restrict mycobacterial growth.

  • 11.
    Eklund, Daniel
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Welin, Amanda
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Andersson, Henrik
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Verma, Deepti
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Pathology and Clinical Genetics.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Särndahl, Eva
    Linköping University, Department of Clinical and Experimental Medicine, Division of Cell Biology. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Human gene variants linked to enhanced NLRP3 activity limit intramacrophage growth of Mycobacterium tuberculosis2014In: The Journal of infectious diseases, ISSN 1537-6613, Vol. 209, no 5, p. 749-753Article in journal (Refereed)
    Abstract [en]

    Activation of the NLRP3 inflammasome and subsequent generation of IL-1β is initiated in macrophages upon recognition of several stimuli. In the present work, we show that gain-of-function gene variants of inflammasome components known to predispose individuals to inflammatory disorders have a host-protective role during infection with Mycobacterium tuberculosis. By isolation of macrophages from patients and healthy blood donors with genetic variants in NLRP3 and CARD8 and subsequently infecting the cells by virulent M. tuberculosis, we show that these gene variants, combined, are associated with increased control of bacterial growth in human macrophages.

  • 12.
    Eklund, Daniel
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Welin, Amanda
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    A medium-throughput microplate-based ex vivo model for measuring intramacrophage growth of mycobacterium tuberculosis in CYTOKINE, vol 48, issue 1-2, pp 14-142009In: CYTOKINE, 2009, Vol. 48, no 1-2, p. 14-14Conference paper (Refereed)
    Abstract [en]

    n/a

  • 13.
    Eklund, Daniel
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Welin, Amanda
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Schon, Thomas
    Kalmar County Hospital.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Huygen, Kris
    Science Institute for Public Health, Belgium .
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Validation of a Medium-Throughput Method for Evaluation of Intracellular Growth of Mycobacterium tuberculosis2010In: Clinical and Vaccine Immunology, ISSN 1556-6811, E-ISSN 1556-679X, Vol. 17, no 4, p. 513-517Article in journal (Refereed)
    Abstract [en]

    Intracellular pathogens such as Mycobacterium tuberculosis have adapted to a life inside host cells, in which they utilize host nutrients to replicate and spread. Ineffective methods for the evaluation of growth of intracellular pathogens in their true environment pose an obstacle for basic research and drug screening. Here we present the validation of a luminometry-based method for the analysis of intramacrophage growth of M. tuberculosis. The method, which is performed in a medium-throughput format, can easily be adapted for studies of other intracellular pathogens and cell types. The use of host cells in drug-screening assays dedicated to find antimicrobials effective against intracellular pathogens permits the discovery of not only novel antibiotics but also compounds with immunomodulatory and virulence-impairing activities, which may be future alternatives or complements to antibiotics.

  • 14.
    Forsberg, Maria
    et al.
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Blomgran, Robert
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Lem, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Särndahl, Eva
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Sebti, Said M.
    Drug Discovery Program, H. Lee Moffitt Cancer Center & Research Institute, Department of Oncology, University of South Florida, Tampa.
    Hamilton, Andrew
    Department of Chemistry, Yale University, New Haven, Connecticut .
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Zheng, Limin
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Differential effects of invasion by and phagocytosis of Salmonella typhimurium on apoptosis in human macrophages: potential role of Rho–GTPases and Akt2003In: Journal of Leukocyte Biology, ISSN 0741-5400, E-ISSN 1938-3673, Vol. 74, no 4, p. 620-629Article in journal (Refereed)
    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.

  • 15.
    Idh, Jonna
    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, Blanka
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Lerm, Maria
    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.
    Raffetseder, Johanna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Eklund, Daniel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Neuro and Inflammation Science. Linköping University, Faculty of Medicine and Health Sciences.
    Woksepp, Hanna
    Linneaus University, Sweden; Kalmar County Hospital, Sweden.
    Werngren, Jim
    Public Health Agency Sweden, Sweden.
    Mansjo, Mikael
    Public Health Agency Sweden, Sweden.
    Sundqvist, Tommy
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Medicine and Health Sciences.
    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. Linneaus University, Sweden; Kalmar County Hospital, Sweden.
    Reduced susceptibility of clinical strains of Mycobacterium tuberculosis to reactive nitrogen species promotes survival in activated macrophages2017In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 12, no 7, article id e0181221Article in journal (Refereed)
    Abstract [en]

    Background Drugs such as isoniazid (INH) and pretomanid (PRT), used against Mycobacterium tuberculosis are active partly through generation of reactive nitrogen species (RNS). The aim of this study was to explore variability in intracellular susceptibility to nitric oxide (NO) in clinical strains of M. tuberculosis. Method Luciferase-expressing clinical M. tuberculosis strains with or without INH resistance were exposed to RNS donors (DETA/NO and SIN-1) in broth cultures and bacterial survival was analysed by luminometry. NO-dependent intracellular killing in a selection of strains was assessed in interferon gamma/lipopolysaccharide-activated murine macrophages using the NO inhibitor L-NMMA. Results When M. tuberculosis H37Rv was compared to six clinical isolates and CDC1551, three isolates with inhA mediated INH resistance showed significantly reduced NO-susceptibility in broth culture. All strains showed a variable but dose-dependent susceptibility to RNS donors. Two clinical isolates with increased susceptibility to NO exposure in broth compared to H37Rv were significantly inhibited by activated macrophages whereas there was no effect on growth inhibition when activated macrophages were infected by clinical strains with higher survival to NO exposure in broth. Furthermore, the most NO-tolerant clinical isolate showed increased resistance to PRT both in broth culture and the macrophage model compared to H37Rv in the absence of mutational resistance in genes associated to reduced susceptibility against PRT or NO. Conclusion In a limited number of clinical M. tuberculosis isolates we found a significant difference in susceptibility to NO between clinical isolates, both in broth cultures and in macrophages. Our results indicate that mycobacterial susceptibility to cellular host defence mechanisms such as NO need to be taken into consideration when designing new therapeutic strategies.

  • 16.
    Idh, Jonna
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Raffetseder, Johanna
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Eklund, Daniel
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Larsson, Marie
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology. Linköping University, Faculty of Health Sciences.
    Pienaar, Elsje
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Forslund, Tony
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Werngren, Jim
    Department of Preparedness, Unit of Highly Pathogenic Microorganisms, Swedish Institute for Communicable Disease Control, Sweden.
    Juréen, Pontus
    Department of Preparedness, Swedish Institute for Communicable Disease Control, Sweden.
    Ängeby, Kristian
    Department of Clinical Microbiology, Karolinska Institute, Karolinska University Hospital, Sweden.
    Sundqvist, Tommy
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Schön, Thomas
    Department of Infectious Diseases and Clinical Microbiology, Kalmar County Hospital, Sweden.
    Susceptibility of Clinical Strains of Mycobacterium tuberculosis to Reactive Nitrogen Species in Activated MacrophagesManuscript (preprint) (Other academic)
    Abstract [en]

    Background: Nitric oxide (NO) is produced in macrophages by the inducible NO synthase (iNOS) upon activation by pro-inflammatory cytokines. NO has been shown to be essential for the control of Mycobacterium tuberculosis infection in murine models whereas its importance in man is not as clear. There is a lack of studies regarding the susceptibility to reactive nitrogen species (RNS) in clinical strains of M. tuberculosis and the relation to first-line drug resistance, such as to isoniazid (INH). The aim of this study was to explore susceptibility to RNS and intracellular survival of clinical strains of M. tuberculosis, with or without INH resistance.

    Method: Seven clinical strains of M. tuberculosis were transformed with the pSMT1-plasmid encoding Vibrio harveyi luciferase. Survival was analysed by luminometry following exposure to the NO donor DETA/NO or peroxynitrite (SIN-1). Intracellular killing was studied in murine macrophages (RAW 264.7) activated with interferon gamma (IFN-γ) and lipopolysaccharide (LPS).

    Results: There was a significant effect on growth control of M. tuberculosis strains upon macrophage activation, which showed variability among clinical isolates. In the cell-free system, all strains showed a dose-dependent susceptibility to DETA/NO and SIN-1, and clinical strains were in general more resistant than H37Rv to DETA/NO. INH-resistant strains with an inhA mutation were significantly more tolerant to DETA/NO than inhA wild type.

    Conclusion: Reactive nitrogen species inhibited growth of clinical M. tuberculosis isolates both in an intra- and extracellular model with significant difference between strains. Increased tolerance to NO was associated with isoniazid resistance mediated by inhA.

  • 17.
    Idh, Jonna
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Mekonnen, M.
    Department of Microbiology, Immunology and Parasitology, Addis Ababa University, Ethiopia.
    Abate, E.
    Armauer Hansen Research Institute, Ethiopia.
    Wedajo, W.
    Armauer Hansen Research Institute, Ethiopia.
    Werngren, J.
    Department of Preparedness, Unit of Highly Pathogenic Microorganisms, Swedish Institute for Communicable Disease Control, Sweden.
    Ängeby, K.
    Clinical Microbiology, MTC, Karolinska Institute, Karolinska University Hospital, Sweden.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Elias, D.
    University of Southern Denmark, Institute of Molecular Medicine, Department of Cancer and Inflammation, Denmark.
    Sundqvist, Tommy
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Aseffa, A.
    Armauer Hansen Research Institute, Ethiopia.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Schön, T.
    Department of Infectious Diseases and Department of Clinical Microbiology, Kalmar County Hospital, Sweden.
    Resistance to First-Line Anti-TB Drugs is Associated with Reduced Nitric Oxide Susceptibility in Mycobacterium tuberculosis2012In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, no 1, p. e39891-Article in journal (Refereed)
    Abstract [en]

    Background and objective: The relative contribution of nitric oxide (NO) to the killing of Mycobacterium tuberculosis in human tuberculosis (TB) is controversial, although this has been firmly established in rodents. Studies have demonstrated that clinical strains of M. tuberculosis differ in susceptibility to NO, but how this correlates to drug resistance and clinical outcome is not known.

    Methods: In this study, 50 sputum smear- and culture-positive patients with pulmonary TB in Gondar, Ethiopia were included. Clinical parameters were recorded and drug susceptibility profile and spoligotyping patterns were investigated. NO susceptibility was studied by exposing the strains to the NO donor DETA/NO.

    Results: Clinical isolates of M. tuberculosis showed a dose- and time-dependent response when exposed to NO. The most frequent spoligotypes found were CAS1-Delhi and T3_ETH in a total of nine known spoligotypes and four orphan patterns. There was a significant association between reduced susceptibility to NO (>10% survival after exposure to 1mM DETA/NO) and resistance against first-line anti-TB drugs, in particular isoniazid (INH). Patients infected with strains of M. tuberculosis with reduced susceptibility to NO showed no difference in cure rate or other clinical parameters, but a tendency towards lower rate of weight gain after two months of treatment.

    Conclusion: There is a correlation between resistance to first-line anti-TB drugs and reduced NO susceptibility in clinical strains of M. tuberculosis. Further studies including the mechanisms of reduced NO susceptibility are warranted and could identify targets for new therapeutic interventions.

  • 18.
    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.

  • 19.
    Kumar, Manish
    et al.
    Department of Chemistry, Bose Institute, Kolkata 700009, India.
    Sahu, Sanjaya Kumar
    Department of Chemistry, Bose Institute, Kolkata 700009, India.
    Kumar, Ranjeet
    Department of Chemistry, Bose Institute, Kolkata 700009, India.
    Subuddhi, Arijita
    Department of Chemistry, Bose Institute, Kolkata 700009, India.
    Maji, Ranjan Kumar
    Bioinformatics Centre, Bose Institute, Kolkata 700054, India.
    Jana, Kuladip
    Division of Molecular Medicine, Bose Institute, Kolkata 700054, India.
    Gupta, Pushpa
    National Jalma Institute for Leprosy and Other Mycobacterial Diseases, Tajganj, Agra 282006, India.
    Raffetseder, Johanna
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Ghosh, Zhumur
    Bioinformatics Centre, Bose Institute, Kolkata 700054, India.
    van Loo, Geert
    VIB Inflammation Research Center, Ghent University, 9052 Ghent / Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium.
    Beyaert, Rudi
    VIB Inflammation Research Center, Ghent University, 9052 Ghent / Department of Biomedical Molecular Biology, Ghent University, 9052 Ghent, Belgium.
    Gupta, Umesh D
    National Jalma Institute for Leprosy and Other Mycobacterial Diseases, Tajganj, Agra 282006, India.
    Kundu, Manikuntala
    Bioinformatics Centre, Bose Institute, Kolkata 700054, India.
    Basu, Joyoti
    Bioinformatics Centre, Bose Institute, Kolkata 700054, India.
    MicroRNA let-7 Modulates the Immune Response to Mycobacterium tuberculosis Infection via Control of A20, an Inhibitor of the NF-κB Pathway.2015In: Cell host & microbe, ISSN 1934-6069, Vol. 17, no 3, p. 345-56Article in journal (Refereed)
    Abstract [en]

    The outcome of the interaction between Mycobacterium tuberculosis (Mtb) and a macrophage depends on the interplay between host defense and bacterial immune subversion mechanisms. MicroRNAs critically regulate several host defense mechanisms, but their role in the Mtb-macrophage interplay remains unclear. MicroRNA profiling of Mtb-infected macrophages revealed the downregulation of miR-let-7f in a manner dependent on the Mtb secreted effector ESAT-6. We establish that let-7f targets A20, a feedback inhibitor of the NF-κB pathway. Expression of let-7f decreases and A20 increases with progression of Mtb infection in mice. Mtb survival is attenuated in A20-deficient macrophages, and the production of TNF, IL-1β, and nitrite, which are mediators of immunity to Mtb, is correspondingly increased. Further, let-7f overexpression diminishes Mtb survival and augments the production of cytokines including TNF and IL-1β. These results uncover a role for let-7f and its target A20 in regulating immune responses to Mtb and controlling bacterial burden.

  • 20.
    Kälvegren, Hanna
    et al.
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Health Sciences.
    Skoglund, Caroline
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Helldahl, Christian
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Grenegård, Magnus
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Bengtsson, Torbjörn
    Linköping University, Department of Medical and Health Sciences, Pharmacology. Linköping University, Faculty of Health Sciences.
    Toll-like receptor 2 stimulation of platelets is mediated by purinergic P2X1-dependent Ca2+ mobilisation, cyclooxygenase and purinergic P2Y1 and P2Y12 receptor activation2010In: Thrombosis and Haemostasis, ISSN 0340-6245, Vol. 103, no 2, p. 398-407Article in journal (Refereed)
    Abstract [en]

    Toll-like receptor 2 (TLR2), which recognise and respond to conserved microbial pathogen-associated molecular patterns, is expressed on the platelet surface. Furthermore, it has recently been shown that the TLR2/1 agonist Pam(3)CSK(4) stimulates platelet activation. The aim of the present study was to clarify important signalling events in Pam(3)CSK(4)-induced platelet aggregation and secretion. Platelet interaction with Pam(3)CSK(4) and the TLR2/6 agonist MALP-2 was studied by analysing aggregation, ATP-secretion, [Ca2+](i) mobilisation and thromboxane B2 (TxB(2)) production. The results show that Pam(3)CSK(4) but not MALP-2 induces [Ca2+](i) increase, TxB(2) production, dense granule secretion and platelet aggregation. Preincubation of platelets with MALP-2 inhibited the Pam(3)CSK(4)-induced responses. The ATP-secretion and aggregation in Pam(3)CSK(4)-stimulated platelets was impeded by the purinergic P2X(1) inhibitor MRS 2159, the purinergic P2Y(1) and P2Y(12) antagonists MRS 2179 and cangrelor, the phospholipase C inhibitor U73122, the calcium chelator BAPT-AM and aspirin. The calcium mobilisation was lowered by MRS 2159, aspirin and U73122 whereas the TxB(2) production was antagonised by MRS 2159, aspirin and BAPT-AM. When investigating the involvement of the myeloid differentiation factor-88 (MyD88) -dependent pathway, we found that platelets express MyD88 and interleukin 1 receptor-associated kinase (IRAK-1), which are proteins important in TLR signalling. However, Pam(3)CSK(4) did not stimulate a rapid (within 10 minutes) phosphorylation of IRAK-1 in platelets. In conclusion, the results show that Pam(3)CSK(4)-induced platelet aggregation and secretion depends on a P2X(1)-mediated Ca2+ mobilisation, production of TxA(2) and ADP receptor activation. The findings in this study further support a role for platelets in sensing bacterial components.

  • 21.
    Larsson, Marie C
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Microbiology.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Ängeby, Kristian
    Karolinska University Hospital, Hospital, Stockholm, Sweden; University of the West Indies, Kingston, Jamaica.
    Nordvall, Michaela
    Östergötlands Läns Landsting, Center for Diagnostics, Department of Clinical Microbiology.
    Jureen, Pontus
    Public Health Agency of Sweden, Stockholm, Sweden.
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences. Kalmar County Hospital, Sweden; Linnaeus University, Kalmar, Sweden.
    A luciferase-based assay for rapid assessment of drug activity against Mycobacterium tuberculosis including monitoring of macrophage viability2014In: Journal of Microbiological Methods, ISSN 0167-7012, E-ISSN 1872-8359, Vol. 106, p. 146-150Article in journal (Refereed)
    Abstract [en]

    The intracellular (IC) effect of drugs against Mycobacterium tuberculosis (Mtb) is not well established but increasingly important to consider when combining current and future multidrug regimens into the best possible treatment strategies. For this purpose, we developed an IC model based on a genetically modified Mtb H37Rv strain, expressing the Vibrio harvei luciferase (H37Rv-lux) infecting the human macrophage like cell line THP-1. Cells were infected at a low multiplicity of infection (1:1) and subsequently exposed to isoniazid (INH), ethambutol (EMB), amikacin (AMI) or levofloxacin (LEV) for 5 days in a 96-well format. Cell viability was evaluated by Calcein AM and was maintained throughout the experiment. The number of viable H37Rv-lux was determined by luminescence and verified by a colony forming unit analysis. The results were compared to the effects of the same drugs in broth cultures. AMI, EMB and LEV were significantly less effective intracellularly (MIC90: greater than4 mg/L, 8 mg/L and 2 mg/L, respectively) compared to extracellularly (MIC90: 0.5 mg/L for AMI and EMB; 0.25 mg/L for LEV). The reverse was the case for INH (IC: 0.064 mg/L vs EC: 0.25 mg/L). In conclusion, this luciferase based method, in which monitoring of cell viability is included, has the potential to become a useful tool while evaluating the intracellular effects of anti-mycobacterial drugs.

  • 22.
    Lerm, Maria
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Brodin Patcha, Veronika
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Ruishalme, Iida
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Särndahl, Eva
    Linköping University, Department of Clinical and Experimental Medicine, Cellbiology. Linköping University, Faculty of Health Sciences.
    Inactivation of Cdc42 is nessecary for depolymerization of phagosomal F-actin and subsequent phagosomal maturation2007In: Journal of Immunology, ISSN 0022-1767, Vol. 178, no 11, p. 7357-7365Article in journal (Refereed)
    Abstract [en]

    Phagocytosis is a complex process involving the activation of various signaling pathways, such as the Rho GTPases, and the subsequent reorganization of the actin cytoskeleton. In neutrophils, Rac and Cdc42 are activated during phagocytosis but less is known about the involvement of these GTPases during the different stages of the phagocytic process. The aim of this study was to elucidate the role of Cdc42 in phagocytosis and the subsequent phagosomal maturation. Using a TAT-based protein transduction technique, we introduced dominant negative and constitutively active forms of Cdc42 into neutrophil-like HL60 (human leukemia) cells that were allowed to phagocytose IgG-opsonized yeast particles. Staining of cellular F-actin in cells transduced with constitutively active Cdc42 revealed that the activation of Cdc42 induced sustained accumulation of periphagosomal actin. Moreover, the fusion of azurophilic granules with the phagosomal membrane was prevented by the accumulated F-actin. In contrast, introducing dominant negative Cdc42 impaired the translocation per se of azurophilic granules to the periphagosomal area. These results show that efficient phagosomal maturation and the subsequent eradication of ingested microbes in human neutrophils is dependent on a strictly regulated Cdc42. To induce granule translocation, Cdc42 must be in its active state but has to be inactivated to allow depolymerization of the F-actin cage around the phagosome, a process essential for phagolysosome formation.

  • 23.
    Lerm, Maria
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Dockrell, H. M.
    London Sch Hyg and Trop Med, England.
    Addressing diversity in tuberculosis using multidimensional approaches2018In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 284, no 2, p. 116-124Article, review/survey (Refereed)
    Abstract [en]

    Tuberculosis is a complex disease, which can affect many organs other than the lungs. Initial infection may be cleared without inducing immunological memory, or progress directly to primary disease. Alternatively, the infection may be controlled as latent TB infection, that may progress to active tuberculosis at a later stage. There is now a greater understanding that these infection states are part of a continuum, and studies using PET/CT imaging have shown that individual lung granulomas may respond to infection independently, in an un-synchronized manner. In addition, the Mycobacterium tuberculosis organisms themselves can exist in different states: as nonculturable forms, as persisters, as rapidly growing bacteria and a biofilm-forming cording phenotype. The omics approaches of transcriptomics, metabolomics and proteomics can help reveal the mechanisms underlying these different infection states in the host, and identify biosignatures with diagnostic potential, that can predict the development of disease, in progressors as early as 12-18 months before it can be detected clinically, or that can monitor the success of anti-TB therapy. Further insights can be obtained from studies of BCG vaccination and new TB vaccines. For example, epigenetic changes associated with trained immunity and a stronger immune responses following BCG vaccination can be identified. These omics approaches may be particularly valuable when linked to studies of mycobacterial growth inhibition, as a direct read-out of the ability to control mycobacterial growth. The second generation of omics studies is identifying much smaller signatures based on as few as 3 or 4 genes. Thus, narrowing down omics-derived biosignatures to a manageable set of markers now opens the way to field-friendly point of care assays.

  • 24.
    Lerm, Maria
    et al.
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Holm, Åsa
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Seiron, Å.
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Särndahl, E.
    Linköping University, Department of Biomedicine and Surgery, Cell biology. Linköping University, Faculty of Health Sciences.
    Magnusson, Karl-Eric
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Descoteaux, A.
    INRS- Institut Armand-Frappier, Université du Québec, Laval, Québec, Canada.
    Rasmusson, Birgitta
    Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Rac1 and Cdc42 are involved in the periphagosomal F-actin accumulation and inhibition of phagosomal maturation caused by Leishmania donovani lipophosphoglycanManuscript (preprint) (Other academic)
    Abstract [en]

    The intracellular parasite Leishmania donovani survives inside macrophage phagosomes by inhibiting phagosornal maturation. Its main surface glycoconjugate, lipophosphoglycan (LPG), is crucial for survival and essential for the build-up of a coat of F-actin surrounding the phagosome. Previous studies have shown that inhibition of PKCα by LPG is partly responsible for the elevated levels of F-actin around the phagosome (1, 2). This study shows that simultaneous inhibition of Cdc42 and Rac1, members of the Rho family of small GTPases, prevented the accumulation of F-actin around L. donovani containing phagosomes in murine macrophages. Moreover, an LPG-defective L. donovani mutant normally not capable of accumulating F-actin around it's phagosome, displayed elevated amounts of periphagosomal F-actin in cells pre-treated with permanently active forms of Cdc42 and Rac. The lysosomal marker LAMP1 did not translocate normally to phagosomes in these cells, indicating defective phagosomal maturation. We conclude that Cdc42 and Rac are activated by L. donovani in an LPG-dependent manner, and that this activation contributes to the accumulation of periphagosomal F-actin around L. donovani phagosomes. Our results also indicate a direct link between the build-up of periphagosomal F-actinand inhibition of phagosomal mahuation.

  • 25.
    Lerm, Maria
    et al.
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Holm, Åsa
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Seiron, Å
    Särndahl, Eva
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Magnusson, Karl-Eric
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Rasmusson, Birgitta
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Molecular and Clinical Medicine, Medical Microbiology.
    Leishmania donovani requires functional Cdc42 and Rac1 to prevent phagosomal maturation2006In: Infection and Immunity, ISSN 0019-9567, E-ISSN 1098-5522, Vol. 74, no 5, p. 2613-2618Article in journal (Refereed)
    Abstract [en]

    Leishmania donovani promastigotes survive inside macrophage phagosomes by inhibiting phagosomal maturation. The main surface glycoconjugate on promastigotes, lipophosphoglycan (LPG), is crucial for survival and mediates the formation of a protective shell of F-actin around the phagosome. Previous studies have demonstrated that this effect involves inhibition of protein kinase Cα. The present study shows that functional Cdc42 and Rac1 are required for the formation of F-actin around L. donovani phagosomes. Moreover, we present data showing that phagosomes containing LPG-defective L. donovani, which is unable to induce F-actin accumulation, display both elevated levels of periphagosomal F-actin and impaired phagosomal maturation in macrophages with permanently active forms of Cdc42 and Rac1. We conclude that L. donovani engages Cdc42 and Rac1 to build up a protective coat of F-actin around its phagosome to prevent phagosomal maturation. Copyright © 2006, American Society for Microbiology. All Rights Reserved.

  • 26.
    Lerm, Maria
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Netea, M. G.
    Radboud University of Nijmegen, Netherlands.
    Trained immunity: a new avenue for tuberculosis vaccine development2016In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 279, no 4, p. 337-346Article, review/survey (Refereed)
    Abstract [en]

    Adaptive immunity towards tuberculosis (TB) has been extensively studied for many years. In addition, in recent years the profound contribution of innate immunity to host defence against this disease has become evident. The discovery of pattern recognition receptors, which allow innate immunity to tailor its response to different infectious agents, has challenged the view that this arm of immunity is nonspecific. Evidence is now accumulating that innate immunity can remember a previous exposure to a microorganism and respond differently during a second exposure. Although the specificity and memory of innate immunity cannot compete with the highly sophisticated adaptive immune response, its contribution to host defence against infection and to vaccine-induced immunity should not be underestimated and needs to be explored. Here, we present the concept of trained immunity and discuss how this may contribute to new avenues for control of TB.

  • 27.
    Lerm, Maria
    et al.
    Albert-Ludwigs-Universität Freiburg, Germany.
    Pop, Marius
    Albert-Ludwigs-Universität Freiburg, Germany.
    Fritz, Gerhard
    Institut für Toxikologie, Mainz, Germany.
    Aktories, Klaus
    Albert-Ludwigs-Universität Freiburg, Germany.
    Schmidt, Gudula
    Albert-Ludwigs-Universität Freiburg, Germany.
    Proteasomal degradation of cytotoxic necrotizing factor 1-activated rac2002In: Infection and Immunity, ISSN 0019-9567, E-ISSN 1098-5522, Vol. 70, no 8, p. 4053-4058Article in journal (Refereed)
    Abstract [en]

    The cytotoxic necrotizing factor 1 (CNF1) from Escherichia coli has been shown to activate members of the Rho family by deamidation of glutamine 63. This amino acid is essential for hydrolysis of GTP, and any substitution results in a constitutively active Rho. Activation of Rho induces the formation of stress fibers, filopodia, and membrane ruffles due to activation of RhoA, Cdc42, and Rac, respectively. Here we show that the level of endogenous Rac decreased in CNF1-treated HEK293 and HeLa cells. The amount of mRNA remained unaffected, leaving the possibility that Rac is subject to proteolytic degradation. Treatment of cells with lactacystin, an inhibitor of the 26S proteasome, protected Rac from degradation. We have previously shown that CNF1 activates the c-Jun N-terminal kinase (JNK) only transiently in HeLa cells (M. Lerm, J. Selzer, A. Hoffmeyer, U. R. Rapp, K. Aktories, and G. Schmidt, Infect. Immun. 67:496-503, 1998). Here we show that CNF1-induced JNK activation is stabilized in the presence of lactacystin. The data indicate that Rac is degraded by a proteasome-dependent pathway in CNF1-treated cells.

  • 28.
    Lerm, Maria
    et al.
    Institut für Pharmakologie und Toxikologie der Universita«t Freiburg, Germany.
    Schmidt, Gudula
    Institut für Pharmakologie und Toxikologie der Universita«t Freiburg, Germany.
    Aktories, Klaus
    Institut für Pharmakologie und Toxikologie der Universita«t Freiburg, Germany.
    Bacterial protein toxins targeting rho GTPases2000In: FEMS Microbiology Letters, ISSN 0378-1097, E-ISSN 1574-6968, Vol. 188, no 1, p. 1-6Article in journal (Refereed)
    Abstract [en]

    Several bacterial protein toxins target eukaryotic cells by modulating the functions of Rho GTPases that are involved in various signal processes and in the regulation of the actin cytoskeleton. The toxins inhibit Rho functions by ADP-ribosylation or glucosylation and activate them by deamidation and transglutamination. New findings indicate that the GTPases are also targeted by various 'injected' toxins which are introduced into the eukaryotic cells by the type-III secretion system. The injected toxins do not covalently modify Rho GTPases, but manipulate their regulatory GTPase cycle by acting as GTPase-activating proteins or guanine nucleotide exchange factors.

  • 29.
    Lerm, Maria
    et al.
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Schmidt, Gudula
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Goehring, Udo-Michael
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Schirmer, Jörg
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Aktories, Klaus
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Identification of the region of rho involved in substrate recognition by Escherichia coli cytotoxic necrotizing factor 1 (CNF1)1999In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 274, no 41, p. 28999-29004Article in journal (Refereed)
    Abstract [en]

    The Escherichia coli cytotoxic necrotizing factor 1 (CNF1) and the Bordetella dermonecrotic toxin (DNT) activate Rho GTPases by deamidation of Gln(63) of RhoA (Gln(61) of Cdc42 and Rac). In addition, both toxins possess in vitro transglutaminase activity in the presence of primary amines. Here we characterized the region of Rho essential for substrate recognition by the toxins using Rho/Ras chimeras as protein substrates. The chimeric protein Ras55Rho was deamidated or transglutaminated by CNF1. Rat pheochromocytoma PC12 cells microinjected with Ras55Rho developed formation of neurite-like structures after treatment with the CNF1 holotoxin indicating activation of the Ha-Ras chimera and Ras-like effects in intact cells. The Ras59Rho78Ras chimera protein contained the minimal Rho sequence allowing deamidation or transglutamination by CNF1. A peptide covering mainly the switch II region and consisting of amino acid residues Asp(59) through Asp(78) of RhoA was substrate for CNF1. Changes of amino acid residues Arg(68) or Leu(72) of RhoA into the corresponding residues of Ras (R68ARhoA and L72QRhoA) inhibited deamidation and transglutamination of the mutants by CNF1. In contrast to CNF1, DNT did not modify Rho/Ras chimeras or the switch II peptide (Asp(59) through Asp(78)). Glucosylation of RhoA at Thr(37) blocked deamidation by DNT but not by CNF. The data indicate that CNF1 recognizes Rho GTPases exclusively in the switch II region, whereas the substrate recognition by DNT is characterized by additional structural requirements.

  • 30.
    Lerm, Maria
    et al.
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Selzer, J.
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Hoffmeyer, A.
    Institut für medizinische Strahlenkunde und Zellforschung, Universität Würzburg, Germany.
    Rapp, U. R.
    Institut für medizinische Strahlenkunde und Zellforschung, Universität Würzburg, Germany.
    Aktories, K.
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Schmidt, G.
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Deamidation of Cdc42 and Rac by Escherichia coli cytotoxic necrotizing factor 1: activation of c-Jun N-terminal kinase in HeLa cells1999In: Infection and Immunity, ISSN 0019-9567, E-ISSN 1098-5522, Vol. 67, no 2, p. 496-503Article in journal (Refereed)
    Abstract [en]

    Recently, Escherichia coli cytotoxic necrotizing factor 1 (CNF1) was shown to activate the low-molecular-mass GTPase RhoA by deamidation of Gln63, thereby inhibiting intrinsic and GTPase-activating protein (GAP)-stimulated GTPase activities (G. Schmidt, P. Sehr, M. Wilm, J. Selzer, M. Mann, and K. Aktories, Nature 387:725-729, 1997; G. Flatau, E. Lemichez, M. Gauthier, P. Chardin, S. Paris, C. Fiorentini, and P. Boquet, Nature 387:729-733, 1997). Here we report that in addition to RhoA, Cdc42 and Rac also are targets for CNF1 in vitro and in intact cells. Treatment of HeLa cells with CNF1 induced a transient formation of microspikes and formation of membrane ruffles. CNF1 caused a transient 10- to 50-fold increase in the activity of the c-Jun N-terminal kinase. Tryptic peptides of Cdc42 obtained from CNF1-treated cells by immunoprecipitation exhibited an increase in mass of 1 Da compared to control peptides, indicating the deamidation of glutamine 61 by the toxin. The same increase in mass was observed with the respective peptides obtained from CNF1-modified recombinant Cdc42 and Rac1. Modification of recombinant Cdc42 and Rac1 by CNF1 inhibited intrinsic and GAP-stimulated GTPase activities and retarded binding of 2'(3')-O-(N-methylanthraniloyl)GDP. The data suggest that recombinant as well as cellular Cdc42 and Rac are substrates for CNF1.

  • 31.
    Persson, Hans Lennart
    et al.
    Linköping University, Department of Medical and Health Sciences, Pulmonary Medicine. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Respiratory Medicine.
    Eklund, Daniel
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Welin, Amanda
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Paues, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Infectious Diseases. Linköping University, Faculty of Health Sciences.
    Idh, Jonna
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Fransson, Sven-Göran
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Schön, Thomas
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Alveolar macrophages from patients with tuberculosis exhibit reduced capacity of restricting growth of Mycobacterium tuberculosis: a pilot study of vitamin D stimulation in vitro2013In: HOAJ Biology, ISSN 2050-0874Article in journal (Refereed)
    Abstract [en]

    Background: The role of vitamin D supplementation as adjuvant treatment of tuberculosis (TB) has lately attracted increasing interest. Our aim was to investigate the capacity of alveolar macrophages (AMs) from patients with or without exposure to TB to control intracellular growth of virulent Mycobacterium tuberculosis (Mtb).

    Methods: AMs were freshly harvested from the bronchoalveolar lavage fluid of 7 patients with a history of TB (4 patients with previous TB and 3 patients with current TB) and 4 non-TB subjects. The H37Rv strain, genetically modified to express Vibrio harveyi luciferase, was used to determine the growth of Mtb by luminometry in the AMs from study subjects. Cytokine levels in culture supernatants were determined using a flow cytometry-based bead array technique.

    Results: AMs from patients with a TB history were less efficient in restricting Mtb growth. Stimulation with 100 nM1, 25-dihydroxyvitamin D (1,25D3) did not significantly influence the capacity of AMs from any study subjects to control the infection. Out of the cytokines evaluated (TNF-α, IL-1β, IL-10 and IL-12p40) only TNF-α demonstrated detectable levels in culture supernatants, but did not respond to stimulation with 1,25D3.

    Conclusions: We conclude that AMs of TB-patients show reduced ability to control mycobacterial growth in vitro, and, that AMs in this pilot study do no respond to 1, 25D3-stimulation. The former observation supports the concept that innate immunity is crucial for the control of TB infection.

  • 32.
    Persson, Hans Lennart
    et al.
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Jacobson, Petra
    Linköping University, Department of Medical and Health Sciences. Linköping University, Faculty of Health Sciences.
    Eklund, Daniel
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Larsson, Marie C.
    Linköping University, Department of Clinical and Experimental Medicine, Clinical Microbiology. Linköping University, Faculty of Health Sciences.
    Welin, Amanda
    Göteborgs universitet.
    Paues, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Idh, Jonna
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Fransson, Sven-Göran
    Linköping University, Department of Medical and Health Sciences, Radiology. Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Center for Diagnostics, Department of Radiology in Linköping.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Schon, Thomas
    Kalmar länssjukhus.
    Alveolar macrophages from patients with tuberculosis display a reduced capacity to inhibit growth of Mycomacterium tuberculosis2012Conference paper (Other academic)
  • 33.
    Pienaar, Elsje
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    A mathematical model of the initial interaction between Mycobacterium tuberculosis and macrophages2014In: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 342, p. 23-32Article in journal (Refereed)
    Abstract [en]

    There is a large body of literature describing molecular level interactions between Mycobacterium tuberculosis (Mtb) and macrophages. Macrophages initiate a range of anti-bacterial mechanisms in response to infection, and Mtb is capable of surviving and circumventing many of these responses. We apply a computational approach to ask: what are the effects on the cellular level of these opposing interactions? The model considers the interplay between bacterial killing and the pathogen's interference with macrophage function. The results reveal an oscillating balance between host and pathogen, but the balance is transient and varies in length, indicating that stochasticity in the bacterial population or host response could contribute to the diverse incubation periods observed in exposed individuals. The model captures host and strain variation and gives new insight into host-pathogen compatibility and co-evolution.

  • 34.
    Pienaar, Elsje
    et al.
    Linköping University, Department of Clinical and Experimental Medicine. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Correction: A mathematical model of the initial interaction between Mycobacterium tuberculosis and macrophages (vol 342, pg 23, 2014) in JOURNAL OF THEORETICAL BIOLOGY vol 349 pg 1722014In: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 349, p. 1p. 172-172Article in journal (Other academic)
    Abstract [en]

    n/a

  • 35.
    Raffetseder, Johanna
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Iakobachvili, Nino
    Division of Nanoscopy, The Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The Netherlands.
    Loitto, Vesa
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Peters, Peter J.
    Division of Nanoscopy, The Maastricht Multimodal Molecular Imaging Institute, Maastricht University, Maastricht, The 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.
    Retention of EsxA in the Capsule-Like Layer of Mycobacterium tuberculosis Is Associated with Cytotoxicity and Is Counteracted by Lung Surfactant2019In: Infection and Immunity, ISSN 0019-9567, E-ISSN 1098-5522, Vol. 87, no 3, article id e00803-18Article in journal (Refereed)
    Abstract [en]

    Mycobacterium tuberculosis, the pathogen that causes tuberculosis, primarily infects macrophages but withstands the host cells bactericidal effects. EsxA, also called virulence factor 6-kDa early secretory antigenic target (ESAT-6), is involved in phagosomal rupture and cell death. We provide confocal and electron microscopy data showing that M. tuberculosis bacteria grown without detergent retain EsxA on their surface. Lung surfactant has detergent-like properties and effectively strips off this surface-associated EsxA, which advocates a novel mechanism of lung surfactant-mediated defense against pathogens. Upon challenge of human macrophages with these M. tuberculosis bacilli, the amount of surface-associated EsxA rapidly declines in a phagocytosis-independent manner. Furthermore, M. tuberculosis bacteria cultivated under exclusion of detergent exert potent cytotoxic activity associated with bacterial growth. Together, this study suggests that the surface retention of EsxA contributes to the cytotoxicity of M. tuberculosis and highlights how cultivation conditions affect the experimental outcome.

  • 36.
    Raffetseder, Johanna
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Pienaar, Elsje
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Blomgran, Robert
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Eklund, Daniel
    Linköping University, Department of Clinical and Experimental Medicine, Division of Inflammation Medicine. Linköping University, Faculty of Health Sciences.
    Brodin Patcha, Veronika
    Linköping University, Department of Clinical and Experimental Medicine, Division of Clinical Sciences. Linköping University, Faculty of Health Sciences.
    Andersson, Henrik
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Welin, Amanda
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Replication Rates of Mycobacterium tuberculosis in Human Macrophages Do Not Correlate with Mycobacterial Antibiotic Susceptibility2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 11, p. e112426-Article in journal (Refereed)
    Abstract [en]

    The standard treatment of tuberculosis (TB) takes six to nine months to complete and this lengthy therapy contributes to the emergence of drug-resistant TB. TB is caused by Mycobacterium tuberculosis (Mtb) and the ability of this bacterium to switch to a dormant phenotype has been suggested to be responsible for the slow clearance during treatment. A recent study showed that the replication rate of a non-virulent mycobacterium, Mycobacterium smegmatis, did not correlate with antibiotic susceptibility. However, the question whether this observation also holds true for Mtb remains unanswered. Here, in order to mimic physiological conditions of TB infection, we established a protocol based on long-term infection of primary human macrophages, featuring Mtb replicating at different rates inside the cells. During conditions that restricted Mtb replication, the bacterial phenotype was associated with reduced acid-fastness. However, these phenotypically altered bacteria were as sensitive to isoniazid, pyrazinamide and ethambutol as intracellularly replicating Mtb. In support of the recent findings with M. smegmatis, we conclude that replication rates of Mtb do not correlate with antibiotic tolerance.

  • 37.
    Ragnarsson, Eva Ge
    et al.
    Uppsala University.
    Schoultz, Ida
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery .
    Gullberg, Elisabet
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery .
    Carlsson, Anders
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery .
    Tafazoli, Farideh
    Linköping University, Department of health and environment. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology .
    Magnusson, Karl-Eric
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology .
    Söderholm, Johan D
    Linköping University, Faculty of Health Sciences. Linköping University, Department of Clinical and Experimental Medicine, Surgery . Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Artursson, Per
    Uppsala University.
    Yersinia pseudotuberculosis induces transcytosis of nanoparticles across human intestinal villus epithelium via invasin-dependent macropinocytosis2008In: Laboratory Investigation, ISSN 0023-6837, E-ISSN 1530-0307, Vol. 88, no 11, p. 1215-1226Article in journal (Refereed)
    Abstract [en]

    Crohns disease is characterized by a defect in intestinal barrier function, where bacteria are considered the most important inflammation-driving factor. Enteric bacteria, including E. coli and Yersinia spp, affect tight junctions in enterocytes, but little is known about bacterial effects on the transcellular pathway. Our objective was to study the short-term effects of Y. pseudotuberculosis on uptake of nanoparticles across human villus epithelium. Monolayers of human colon epithelium-derived Caco-2 cells and biopsies of normal human ileum were studied after 2 h exposure to Y. pseudotuberculosis expressing (inv+) or lacking (inv-) the bacterial adhesion molecule, invasin. Transepithelial transport of fluorescent nanoparticles (markers of transcytosis) was quantified by flow cytometry, and mechanisms explored by using inhibitors of endocytosis. Epithelial expressions of beta 1-integrin and particle uptake pathways were studied by confocal microscopy. The paracellular pathway was assessed by electrical resistance (TER), mannitol flux, and expression of tight junction proteins occludin and caludin-4 by confocal microscopy. Inv + Y. pseudotuberculosis adhered to the apical surface of epithelial cells and induced transcytosis of exogenous nanoparticles across Caco-2 monolayers (30-fold increase, P < 0.01) and ileal mucosa (268 +/- 47% of control; P < 0.01), whereas inv-bacteria had no effect on transcytosis. The transcytosis was concentration-, particle size-and temperature-dependent, and possibly mediated via macropinocytosis. Y. pseudotuberculosis also induced apical expression of beta 1-integrin on epithelial cells. A slight drop in TER was seen after exposure to inv+ Y. pseudotuberculosis, whereas mannitol flux and tight junction protein expression was unchanged. In summary, Y. pseudotuberculosis induced apical expression of beta 1-integrin and stimulated uptake of nanoparticles via invasin-dependent transcytosis in human intestinal epithelium. Our findings suggest that bacterial factors may initiate transcytosis of luminal exogenous particles across human ileal mucosa, thus presenting a novel mechanism of intestinal barrier dysfunction.

  • 38.
    Ramanarao Parasa, Venkata
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences. Karolinska Institute, Sweden.
    Jubayer Rahman, Muhammad
    Karolinska Institute, Sweden .
    Ngyuen Hoang, Anh Thu
    Karolinska Institute, Sweden .
    Svensson, Mattias
    Karolinska Institute, Sweden .
    Brighenti, Susanna
    Karolinska Institute, Sweden .
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Health Sciences.
    Modeling Mycobacterium tuberculosis early granuloma formation in experimental human lung tissue2014In: Disease Models and Mechanisms, ISSN 1754-8403, E-ISSN 1754-8411, Vol. 7, no 2, p. 281-288Article in journal (Refereed)
    Abstract [en]

    The widely used animal models for tuberculosis ( TB) display fundamental differences from human TB. Therefore, a validated model that recapitulates human lung TB is attractive for TB research. Here, we describe a unique method for establishment of TB infection in an experimental human lung tissue model. The model is based on cell lines derived from human lungs and primary macrophages from peripheral blood, and displays characteristics of human lung tissue, including evenly integrated macrophages throughout the epithelium, production of extracellular matrix, stratified epithelia and mucus secretion. Establishment of experimental infection in the model tissue with Mycobacterium tuberculosis, the bacterium that causes TB, resulted in clustering of macrophages at the site of infection, reminiscent of early TB granuloma formation. We quantitated the extent of granuloma formation induced by different strains of mycobacteria and validated our model against findings in other TB models. We found that early granuloma formation is dependent on ESAT-6, which is secreted via the type VII secretion machinery of virulent mycobacteria. Our model, which can facilitate the discovery of the interactions between mycobacteria and host cells in a physiological environment, is the first lung tissue model described for TB.

  • 39.
    Scheer, Vendela
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Department of Anaesthesiology and Intensive Care in Linköping (ANOPIVA).
    Bergman, Malin
    Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Diagnostics, Department of Clinical Microbiology. Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    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, Center for Diagnostics, Department of Clinical Microbiology.
    Kalén, Anders
    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 Orthopaedics in Linköping.
    Topical benzoyl peroxide application on the shoulder reduces Propionibacterium acnes: a randomized study2018In: Journal of shoulder and elbow surgery, ISSN 1058-2746, E-ISSN 1532-6500, Vol. 27, no 6, p. 957-961Article in journal (Refereed)
    Abstract [en]

    Background: Propionibacterium acnes is a common cause of infection following shoulder surgery. Studies have shown that standard surgical preparation does not eradicate P acnes. The purpose of this study was to examine whether topical application of benzoyl peroxide (BPO) gel could decrease the presence of P acnes compared with todays standard treatment with chlorhexidine soap (CHS). We also investigated and compared the recolonization of the skin after surgical preparation and draping between the BPO- and CHS-treated groups. Methods: In this single-blinded nonsurgical study, 40 volunteers-24 men and 16 women-were randomized to preoperative topical treatment at home with either 5% BPO or 4% CHS on the left shoulder at the area of a deltopectoral approach. Four skin swabs from the area were taken in a standardized manner at different times: before and after topical treatment, after surgical skin preparation and sterile draping, and 120 minutes after draping. Results: Topical treatment with BPO significantly reduced the presence of P acnes measured as the number of colony-forming units on the skin after surgical preparation. P acnes was found in 1 of 20 subjects in the BPO group and 7 of 20 in the CHS group (P = .044). The results remained after 2 hours (P = .048). Conclusion: Topical preparation with BPO before shoulder surgery may be effective in reducing P acnes on the skin and preventing recolonization. Conclusion: Topical preparation with BPO before shoulder surgery may be effective in reducing P acnes on the skin and preventing recolonization. (C) 2018 Journal of Shoulder and Elbow Surgery Board of Trustees. All rights reserved.

  • 40.
    Schmidt, Gudula
    et al.
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Goehring, Udo-Michael
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Schirmer, Jörg
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Strasse 5, D-79104 Freiburg, Germany.
    Lerm, Maria
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Germany.
    Aktories, Klaus
    Institut für Pharmakologie und Toxikologie der Albert-Ludwigs-Universität Freiburg, Hermann-Herder-Strasse 5, D-79104 Freiburg, Germany.
    Identification of the C-terminal part of Bordetella dermonecrotic toxin as a transglutaminase for rho GTPases1999In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 274, no 45, p. 31875-31881Article in journal (Refereed)
    Abstract [en]

    Bordetella dermonecrotic toxin (DNT) causes the deamidation of glutamine 63 of Rho. Here we identified the region of DNT harboring the enzyme activity and compared the toxin with the cytotoxic necrotizing factor 1, which also deamidates Rho. The DNT fragment (DeltaDNT) covering amino acid residues 1136-1451 caused deamidation of RhoA at glutamine 63 as determined by mass spectrometric analysis and by the release of ammonia. In the presence of dansylcadaverine or ethylenediamine, DeltaDNT caused transglutamination of Rho. Deamidase and transglutaminase activities were blocked in the mutant proteins Cys(1292) --> Ala, His(1307) --> Ala, and Lys(1310) --> Ala of DeltaDNT. Deamidation and transglutamination induced by DeltaDNT blocked intrinsic and Rho- GTPase-activating protein-stimulated GTPase activity of RhoA. DeltaDNT deamidated and transglutaminated Rac and Cdc42 in the absence and presence of ethylenediamine, respectively. Modification of Rho proteins by DeltaDNT was nucleotide-dependent and did not occur with GTPgammaS-loaded GTPases. In contrast to cytotoxic necrotizing factor, which caused the same kinetics of ammonia release in the absence and presence of ethylenediamine, ammonia release by DeltaDNT was largely increased in the presence of ethylenediamine, indicating that DeltaDNT acts primarily as a transglutaminase.

  • 41.
    Schmidt, Gudula
    et al.
    Albert-Ludwigs-Universität Freiburg, Germany.
    Selzer, Jörg
    Albert-Ludwigs-Universität Freiburg, Germany.
    Lerm, Maria
    Albert-Ludwigs-Universität Freiburg, Germany.
    Aktories, Klaus
    Albert-Ludwigs-Universität Freiburg, Germany.
    The Rho-deamidating cytotoxic necrotizing factor 1 from Escherichia coli possesses transglutaminase activity. Cysteine 866 and histidine 881 are essential for enzyme activity1998In: Journal of Biological Chemistry, ISSN 0021-9258, E-ISSN 1083-351X, Vol. 273, no 22, p. 13669-13674Article in journal (Refereed)
    Abstract [en]

    Recently, it has been reported that cytotoxic necrotizing factor 1 (CNF1) from Escherichia coli induces formation of stress fibers by deamidation of glutamine 63 of RhoA (Schmidt, G., Sehr, P., Wilm, M., Selzer, J., Mann, M., and Aktories, K. (1997) Nature 387, 725-729); Flatau, G., Lemichez, E., Gauthier, M., Chardin, P., Paris, S., Fiorentini, C., and Boquet, P. (1997) Nature 387, 729-733). By using mass spectrometric analysis, we show now that the toxin transfers ethylenediamine, putrescine, and dansylcadaverine specifically onto glutamine 63 of RhoA. RhoA was also a substrate for guinea pig liver transglutaminase, which modified not only glutamine 63, but also glutamine residues at positions 52 and 136. Treatment of the fully active N-terminal fragment of CNF1 (amino acid residues 709-1014) with iodoacetamide inhibited both deamidation and transglutamination activities. Moreover, exchange of cysteine 866 with serine blocked the enzyme activity of the N-terminal CNF1 fragment. In addition, we identified histidine 881 to be essential for the enzyme activity of CNF1. The data indicate that CNF1 shares a catalytic dyad of cysteine and histidine residues with eukaryotic transglutaminases and cysteine proteases.

  • 42.
    Schon, T
    et al.
    Kalmar County Hospital, Sweden .
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Stendahl, Olle
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology. Linköping University, Faculty of Health Sciences.
    Shortening the short-course therapy-insights into host immunity may contribute to new treatment strategies for tuberculosis2013In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 273, no 4, p. 368-382Article, review/survey (Refereed)
    Abstract [en]

    Schon T, Lerm M, Stendahl O (Kalmar County Hospital, Kalmar; and Linkoping University, Linkoping; Sweden). Shortening the short-course therapy: insights into host immunity may contribute to newtreatment strategies for tuberculosis (Review). J Intern Med 2013; 273: 368-382. Achieving global control of tuberculosis (TB) is a great challenge considering the current increase in multidrug resistance and mortality rate. Considerable efforts are therefore being made to develop new effective vaccines, more effective and rapid diagnostic tools as well as new drugs. Shortening the duration of TB treatment with revised regimens and modes of delivery of existing drugs, as well as development of new antimicrobial agents and optimization of the host response with adjuvant immunotherapy could have a profound impact on TB cure rates. Recent data show that chronic worm infection and deficiencies in micronutrients such as vitamin D and arginine are potential areas of intervention to optimize host immunity. Nutritional supplementation to enhance nitric oxide production and vitamin D-mediated effector functions as well as the treatment of worm infection to reduce immunosuppressive effects of regulatory T (Treg) lymphocytes may be more suitable and accessible strategies for highly endemic areas than adjuvant cytokine therapy. In this review, we focus mainly on immune control of human TB, and discuss how current treatment strategies, including immunotherapy and nutritional supplementation, could be optimized to enhance the host response leading to more effective treatment.

  • 43.
    Schoultz, Ida
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Carlsson, Anders
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Gullberg, Elisabet
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Almer, Sven
    Linköping University, Department of Clinical and Experimental Medicine, Gastroenterology and Hepatology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Endocrinology and Gastroenterology.
    Ström, Magnus
    Linköping University, Department of Clinical and Experimental Medicine, Gastroenterology and Hepatology . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Local Health Care Services in Central Östergötland, Department of Endocrinology and Gastroenterology.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    McKay, Derek M.
    Department of Physiology and Biophysics, University of Calgary, Calgary, Canada.
    Rhodes, Jonathan M.
    Department of Medicine, Henry Wellcome Laboratory of Molecular and Cellular Gastroenterology, University of Liverpool, Liverpool, United Kingdom.
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Infliximab reduces bacterial uptake in mucosal biopsies of Crohn’s colitis viamicrotubule-dependent pathwayManuscript (preprint) (Other academic)
    Abstract [en]

    Background: A defective intestinal barrier, shown by increased paracellular permeability is an importantpathogenic factor in Crohn’s disease (CD). TNFα is a key mediator in the regulation of the intestinal barrierfunction. Treatment with antibodies directed against TNFα, such as infliximab, has been established as animportant part of the therapeutic arsenal in severe Crohn’s disease, but the mechanisms of action have yet tobe elucidated. Part of infliximab’s effect has been suggested to be reduced apoptosis of epithelial cells andthereby reduced paracellular permeability. Our aim was to study how infliximab affects uptake of adherent E.coli across the colonic mucosa in CD.

    Method: Seven patients with active CD colitis were examined before and after a four week treatment withinfliximab. Control biopsies were taken from healthy volunteers (4) and patients undergoing controlexamination for colonic polyps (4), aged 36 (range 25-81), coloscopy. Biopsies were taken from macroscopicallynon-inflamed descending colon and were mounted in Ussing chambers to study barrier function. Transmucosalpassage of green fluorescent protein (GFP) incorporated E. coli HM427, an adherent bacteria isolated from thecolon of a CD patient, was studied by quantifying the translocated fluorescent bacteria using flow cytometry.

    Results: Bacterial passage across the colonic mucosa was increased in CD (2500 ± 300 arb. units) comparedwith controls (960 ± 280; p<0.05), and was reduced to 500 ± 200 units after the infliximab treatment (p<0.05).In biopsies treated with colchicine (a microtubuline inhibitor) uptake of E. coli HM427 was reduced by 2/3compared to non-treated biopsies.

    Conclusion: Patients with active Crohn’s disease showed a defect in the barrier to adherent E. coli, which waspartly mediated through a microtubule dependent uptake. The four week treatment with infliximab improvedthe intestinal barrier to these bacteria. This may constitute an important part of infliximab’s mechanisms ofaction in active colitis.

  • 44.
    Schoultz, Ida
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Kufer, Thomas
    Institute for Medical Microbiology, Immunology and Hygiene, University of Cologne, Germany.
    Jiang, Tieshan
    Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Jandu, Narveen
    University of Toronto, Toronto, Canada.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Ubiquitination and degradation of the Crohn’s Disease associated protein Nod2involves the E2 enzyme UBE2G2Manuscript (preprint) (Other academic)
    Abstract [en]

    Background: Mutations predisposing to Crohn’s disease (CD) have been mapped to the CARD15/Nod2 locus,which encodes a cytoplasmic receptor hereafter referred to as Nod2, a member of the NACHT-LRR (NLR) familyof pattern recognition receptors. The binding of bacterial muramyl dipeptide (MDP) to Nod2 triggers theactivation of the nuclear factor-κB (NFκB) pathway, thereby inducing a number of pro-inflammatory genes. Themost common variant of Nod2 associated with CD is the frame shift mutation L1007fs, which results in atruncated form of the protein unable to respond to MDP. Despite active research, little is known about howNod2 is regulated. The aim of this study was to investigate if the cellular Nod2 protein level is regulated by theubiquitin-proteasome pathway.

    Material and Methods/Results: Nod2 was shown to be subjected to rapid turnover in the colorectal cancer cellline SW480 as measured by immunoprecipitation following inhibition of protein synthesis with cyklohexamide.Immunoprecipitation of Nod2 also revealed co-precipitation of ubiquitin, suggesting that Nod2 wasubiquitinated. In line with this observation, inhibition of the proteasome using MG-132 or lactacystin, resultedin increased levels of Nod2 in the cells. UBE2G2, an E2 enzyme, thus conferring specificity of ubiquitin binding,was identified to have affinity for the CARD domain of Nod2. Activation of Nod2 with MDP enhanced itsubiquitination, and increasing amounts of UBE2G2 in the cells abrogated NFB-activation, suggesting thatubiquitination of Nod2 may be important for the resolution of the inflammatory signal.

    Conclusion: Taken together, our results show that the cellular level of Nod2 protein is regulated via theubiquitin-proteasome pathway, suggesting that Nod2-driven inflammation may be resolved through rapiddegradation of Nod2. Consequently, not only polymorphisms in Nod2 directly, but also in genes regulatingNod2 protein levels may contribute to the susceptibility to Crohn’s disease.

  • 45.
    Schoultz, Ida
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences.
    Verma, Deepti
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Halfvarsson, Jonas
    Örebro University Hospital.
    Torkvist, Leif
    Karolinska University Hospital.
    Fredrikson, Mats
    Linköping University, Department of Clinical and Experimental Medicine, Occupational and Environmental Medicine . Linköping University, Faculty of Health Sciences.
    Sjoqvist, Urban
    Karolinska University Hospital.
    Lordal, Mikael
    Karolinska University Hospital.
    Tysk, Curt
    Örebro University Hospital.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Medical Microbiology . Linköping University, Faculty of Health Sciences.
    Söderkvist, Peter
    Linköping University, Department of Clinical and Experimental Medicine, Cell Biology. Linköping University, Faculty of Health Sciences.
    Söderholm, Johan D
    Linköping University, Department of Clinical and Experimental Medicine, Surgery . Linköping University, Faculty of Health Sciences. Östergötlands Läns Landsting, Centre of Surgery and Oncology, Department of Surgery in Östergötland.
    Combined Polymorphisms in Genes Encoding the Inflammasome Components NALP3 and CARD8 Confer Susceptibility to Crohns Disease in Swedish Men2009In: American Journal of Gastroenterology, ISSN 0002-9270, E-ISSN 1572-0241, Vol. 104, no 5, p. 1180-1188Article in journal (Refereed)
    Abstract [en]

    OBJECTIVES : Crohns disease (CD) is characterized by overproduction of proinflammatory cytokines like interleukin (IL)-1 beta. Production of mature IL-1 beta is dependent on a caspase-1-activating protein complex called the NALP3 inflammasome, composed of NALP3, ASC, and CARD8. NALP3 shares structural similarities with Nod2, and both of these proteins are required for bacteria-induced IL-1 beta secretion. The combination of the polymorphisms CARD8 (C10X) and NALP3 (Q705K) was recently shown to be associated with rheumatoid arthritis. Our aim was to investigate whether these combined polymorphisms play a role in the susceptibility to CD.

    METHODS: The study included 498 CD patients in two cohorts from different regions and 742 control individuals from a Swedish population. DNA was isolated from whole blood. Polymorphisms of (Q705K) NALP3 and (C10X) CARD8, as well as the Nod2 variants, R702W and G908R, were genotyped using the Taqman single nucleotide polymorphism assay. The Nod2 frameshift mutation, L1007fs, was detected by Megabace SNuPe genotyping.

    RESULTS: Our results show that men who have both the C10X and Q705K alleles in CARD8 and NALP3, and who express wild-type alleles of Nod2 are at an increased risk of developing CD (odds ratio, OR: 3.40 range: 1.32-8.76); P = 0.011). No association with these polymorphisms was found in women (OR: 0.89 (range: 0.44-1.77); P = 0.74).

    CONCLUSIONS: We suggest a role for combined polymorphisms in CARD8 and NALP3 in the development of CD in men, with obvious sex differences in the genetic susceptibility pattern. These findings give further support to the importance of innate immune responses in CD.

  • 46.
    Tenland, Erik
    et al.
    Lund Univ, Sweden.
    Krishnan, Nitya
    Imperial Coll London, England.
    Ronnholin, Anna
    Lund Univ, Sweden.
    Kalsum, Sadaf
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Puthia, Manoj
    Lund Univ, Sweden.
    Morgelin, Matthias
    Cobsyx AB, Sweden.
    Davoudi, Mina
    Lund Univ, Sweden.
    Otrocka, Magdalena
    Karolinska Inst, Sweden.
    Alaridah, Nader
    Lund Univ, Sweden.
    Glegola-Madejska, Izabela
    Imperial Coll London, England.
    Sturegard, Erik
    Lund Univ, Sweden.
    Schmidtchen, Artur
    Lund Univ, Sweden.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Robertson, Brian D.
    Imperial Coll London, England.
    Godaly, Gabriela
    Lund Univ, Sweden.
    A novel derivative of the fungal antimicrobial peptide plectasin is active against Mycobacterium tuberculosis2018In: Tuberculosis, ISSN 1472-9792, E-ISSN 1873-281X, Vol. 113, p. 231-238Article in journal (Refereed)
    Abstract [en]

    Tuberculosis has been reaffirmed as the infectious disease causing most deaths in the world. Co-infection with HIV and the increase in multi-drug resistant Mycobacterium tuberculosis strains complicate treatment and increases mortality rates, making the development of new drugs an urgent priority. In this study we have identified a promising candidate by screening antimicrobial peptides for their capacity to inhibit mycobacterial growth. This non-toxic peptide, NZX, is capable of inhibiting both clinical strains of M. tuberculosis and an MDR strain at therapeutic concentrations. The therapeutic potential of NZX is further supported in vivo where NZX significantly lowered the bacterial load with only five days of treatment, comparable to rifampicin treatment over the same period. NZX possesses intracellular inhibitory capacity and co-localizes with intracellular bacteria in infected murine lungs. In conclusion, the data presented strongly supports the therapeutic potential of NZX in future anti-TB treatment.

  • 47.
    Tenland, Erik
    et al.
    Lund Univ, Sweden.
    Pochert, Alexander
    Ulm Univ, Germany.
    Krishnan, Nitya
    Imperial Coll London, England.
    Rao, Komal Umashankar
    Lund Univ, Sweden.
    Kalsum, Sadaf
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Braun, Katharina
    Lund Univ, Sweden.
    Glegola-Madejska, Izabela
    Imperial Coll London, England.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Robertson, Brian D.
    Imperial Coll London, England.
    Linden, Mika
    Ulm Univ, Germany.
    Godaly, Gabriela
    Lund Univ, Sweden.
    Effective delivery of the anti-mycobacterial peptide NZX in mesoporous silica nanoparticles2019In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 14, no 2, article id e0212858Article in journal (Refereed)
    Abstract [en]

    Background Intracellular delivery of antimicrobial agents by nanoparticles, such as mesoporous silica particles (MSPs), offers an interesting strategy to treat intracellular infections. In tuberculosis (TB), Mycobacterium tuberculosis avoids components of the immune system by residing primarily inside alveolar macrophages, which are the desired target for TB therapy. Methods and findings We have previously identified a peptide, called NZX, capable of inhibiting both clinical and multi-drug resistant strains of M. tuberculosis at therapeutic concentrations. In this study we analysed the potential of MSPs containing NZX for the treatment of tuberculosis. The MSPs released functional NZX gradually into simulated lung fluid and the peptide filled MSPs were easily taken up by primary macrophages. In an intracellular infection model, the peptide containing particles showed increased mycobacterial killing compared to free peptide. The therapeutic potential of peptide containing MSPs was investigated in a murine infection model, showing that MSPs preserved the effect to eliminate M. tuberculosis in vivo. Conclusions In this study we found that loading the antimicrobial peptide NZX into MSPs increased the inhibition of intracellular mycobacteria in primary macrophages and preserved the ability to eliminate M. tuberculosis in vivo in a murine model. Our studies provide evidence for the feasibility of using MSPs for treatment of tuberculosis.

  • 48.
    Tukenmez, Hasan
    et al.
    Umea Univ, Sweden.
    Edstrom, Isabel
    Umea Univ, Sweden.
    Kalsum, Sadaf
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Braian, Clara
    Not Found:Linkoping Univ, Dept Clin and Expt Med, SE-58183 Linkoping, Sweden.
    Ummanni, Ramesh
    CSIR IICT, India.
    Fick, Stina Berglund
    Umea Univ, Sweden.
    Sundin, Charlotta
    Umea Univ, Sweden.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Elofsson, Mikael
    Umea Univ, Sweden.
    Larsson, Christer
    Umea Univ Hosp, Sweden.
    Corticosteroids protect infected cells against mycobacterial killing in vitro2019In: Biochemical and Biophysical Research Communications - BBRC, ISSN 0006-291X, E-ISSN 1090-2104, Vol. 511, no 1, p. 117-121Article in journal (Refereed)
    Abstract [en]

    The effect of corticosteroids on human physiology is complex and their use in tuberculosis patients remains controversial. In a high-throughput screening approach designed to discover virulence inhibitors, several corticosteroids were found to prevent cytolysis of fibroblasts infected with mycobacteria. Further experiments with Mycobacterium tuberculosis showed anti-cytolytic activity in the 10 nM range, but no effect on bacterial growth or survival in the absence of host cells at 20 mu M. The results from a panel of corticosteroids with various affinities to the glucocorticoid- and mineralocorticoid receptors indicate that the inhibition of cytolysis most likely is mediated through the glucocorticoid receptor. Using live-imaging of M. tuberculosis-infected human monocyte-derived macrophages, we also show that corticosteroids to some extent control intracellular bacteria. In vitro systems with reduced complexity are to further study and understand the interactions between bacterial infection, immune defense and cell signaling. (C) 2019 The Authors. Published by Elsevier Inc.

  • 49.
    Venkata Ramanarao, Parasa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Muvva, Jagadeeswara R.
    Karolinska Institute, Sweden.
    Rose, Jeronimo F.
    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.
    Brighenti, Susanna
    Karolinska Institute, Sweden.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Inhibition of Tissue Matrix Metalloproteinases Interferes with Mycobacterium tuberculosis-Induced Granuloma Formation and Reduces Bacterial Load in a Human Lung Tissue Model2017In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 8, article id 2370Article in journal (Refereed)
    Abstract [en]

    Granulomas are hallmarks of pulmonary tuberculosis (TB) and traditionally viewed as host-protective structures. However, recent evidence suggest that Mycobacterium tuberculosis (Mtb) uses its virulence factors to stimulate the formation of granuloma. In the present study, we investigated the contribution of matrix metalloproteinases (MMPs), host enzymes that cause degradation of the extracellular matrix, to granuloma formation and bacterial load in Mtb-infected tissue. To this end, we used our lung tissue model for TB, which is based on human lung-derived cells and primary human monocyte-derived macrophages. Global inhibition of MMPs in the Mtb-infected tissue model reduced both granuloma formation and bacterial load. The infection caused upregulation of a set of MMPs (MMP1, 3, 9, and 12), and this finding could be validated in lung biopsies from patients with non-cavitary TB. Data from this study indicate that MMP activation contributes to early TB granuloma formation, suggesting that host-directed, MMP-targeted intervention could be considered as adjunct therapy to TB treatment.

  • 50.
    Venkata Ramanarao, Parasa
    et al.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Rose, Jeronimo
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Castillo-Diaz, Luis Alberto
    Ctr Invest and Asistencia Tecnol and Diseno Estado Ja, Mexico.
    de Jesus Aceves-Sanchez, Michel
    Ctr Invest and Asistencia Tecnol and Diseno Estado Ja, Mexico.
    Jazmin Vega-Dominguez, Perla
    Ctr Invest and Asistencia Tecnol and Diseno Estado Ja, Mexico.
    Lerm, Maria
    Linköping University, Department of Clinical and Experimental Medicine, Division of Microbiology and Molecular Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Alberto Flores-Valdez, Mario
    Ctr Invest and Asistencia Tecnol and Diseno Estado Ja, Mexico.
    Evaluation of the immunogenic capability of the BCG strains BCG Delta BCG1419c and BCG Delta BCG1416c in a three-dimensional human lung tissue model2018In: Vaccine, ISSN 0264-410X, E-ISSN 1873-2518, Vol. 36, no 14, p. 1811-1815Article in journal (Refereed)
    Abstract [en]

    Tuberculosis (TB) still remains as an unmet global threat. The current vaccine is not fully effective and novel alternatives are needed. Here, two vaccine candidate strains derived from BCG carrying deletions in the BCG1416c or BCG1419c genes were analysed for their capacity to modulate the cytoldne/chemokine profile and granuloma formation in a human lung tissue model (LTM). We show that the clustering of monocytes, reminiscent of early granuloma formation, in LTMs infected with BCG strains was similar for all of them. However, BCG Delta BCG1419c, like M. tuberculosis, was capable of inducing the production of IL-6 in contrast to the other BCG strains. This work suggests that LTM could be a useful ex vivo assay to evaluate the potential immunogenicity of novel TB vaccine candidates.

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