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  • 1.
    Abuzeid, Nadir
    et al.
    Medical and Aromat Plants Research Institute, Sudan; Omdurman Islamic University, Sudan.
    Kalsum, Sadaf
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Koshy, Richin John
    Larsson, Marie C
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Glader, Mikaela
    Andersson, Henrik
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Raffetseder, Johanna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Pienaar, Elsje
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för inflammationsmedicin. Linköpings universitet, Hälsouniversitetet.
    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
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Antimycobacterial activity of selected medicinal plants traditionally used in Sudan to treat infectious diseases2014Ingår i: Journal of Ethnopharmacology, ISSN 0378-8741, E-ISSN 1872-7573, Vol. 157, s. 134-139Artikel i tidskrift (Refereegranskat)
    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.

  • 2.
    Andersson, Henrik
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Ngoh, Eyler
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Persson, Alexander
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Andersson, Blanka
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Svensson, Kristoffer
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Blomgran, Robert
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Apoptotic neutrophils augment the inflammatory response to Mycobacterium tuberculosis infection in human macrophages2014Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 7, s. e101514-Artikel i tidskrift (Refereegranskat)
    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.

  • 3.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Mycobacterium tuberculosis and the human macrophage: shifting the balance through inflammasome activation2013Doktorsavhandling, sammanläggning (Övrigt vetenskapligt)
    Abstract [en]

    Mycobacterium tuberculosis is a very successful pathogen and tuberculosis constitutes a major threat to global health worldwide. The World Health Organization (WHO) estimates that almost nine million new cases and 1.5 million deaths occur annually and the situation is worsened by increased antibiotic resistance and an extreme synergism with the HIV pandemic. M. tuberculosis primarily affects the lungs where the infection can lead to either eradication of the bacteria or the initiation of an immune response that culminates in the formation of a large cluster of immune cells termed granulomas. In these granulomas, the bacteria can either replicate and cause disease with the ultimate goal of spreading to new hosts or cause latent tuberculosis, which can persist for decades. The tools available to manage the disease are currently suboptimal and include lengthy antibiotic treatments and an inefficient vaccine resulting in poor protection. On a cellular level, M. tuberculosis primarily infects the cell designed to recognize, ingest and eradicate bacteria, namely the human macrophage. Following recognition, the macrophage phagocytoses the bacterium and tries to kill it using an array of different effector mechanisms including acidification of the bacterium-containing vacuole, different degradative enzymes and the generation of radicals. However, the bacterium is able to circumvent many of these harmful effects, leading to a tug-of-war between the bacterium  and host macrophage. This thesis aims at studying the interaction between the human macrophage and M. tuberculosis to identify host factors critical for controlling growth of the bacteria. More specifically, it focuses on the role of an intracellular receptor protein called NLRP3 and its downstream effects. NLRP3 is activated in human macrophages infected by M. tuberculosis and upon activation it forms a multi-protein complex known as the inflammasome. This protein complex is known to induce the production of the proinflammatory cytokine IL-1β and specialized forms of macrophage cell death. We hypothesized that stimulating this pathway would have a beneficial effect for the host macrophage during infection with M. tuberculosis.

    To allow us to follow interaction between M. tuberculosis and the human macrophage, we first developed a luminometry-based method of measuring bacterial numbers and following bacterial growth over several days in infected cells. With this new assay we showed that low numbers of bacteria induced very low levels of IL-1β and failed to induce any type of cell death in the macrophage. However, when a critical number of bacteria were reached, the infected macrophages underwent necrosis, which was accompanied by high levels of IL-1β. We were also able to show that addition of vitamin D, which has been implicated as an important factor for increased killing capacity of infected macrophages, increased the production of IL-1β, which coincided with increased killing of M. tuberculosis. This effect was seen specifically in cells from patients with active tuberculosis, suggesting that these cells are primed to respond to vitamin D and increased levels of IL-1β. Furthermore, we also showed that increasing production of IL-1β by stimulating infected macrophages with apoptotic neutrophils in turn drives the production of other proinflammatory cytokines. Lastly, we showed that gain-of-function polymorphisms in inflammasome components linked to increased inflammasome activation and IL-1β production promotes bacterial killing in human macrophages. In conclusion, the work presented in this thesis shows  that by enhancing the functions of the inflammasome, it is possible to tip the balance between the human macrophage and M. tuberculosis in favor of the host cell.

    Delarbeten
    1. Validation of a Medium-Throughput Method for Evaluation of Intracellular Growth of Mycobacterium tuberculosis
    Öppna denna publikation i ny flik eller fönster >>Validation of a Medium-Throughput Method for Evaluation of Intracellular Growth of Mycobacterium tuberculosis
    Visa övriga...
    2010 (Engelska)Ingår i: Clinical and Vaccine Immunology, ISSN 1556-6811, E-ISSN 1556-679X, Vol. 17, nr 4, s. 513-517Artikel i tidskrift (Refereegranskat) Published
    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.

    Ort, förlag, år, upplaga, sidor
    American Society for Microbiology, 2010
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-54868 (URN)10.1128/CVI.00446-09 (DOI)000276170900004 ()
    Tillgänglig från: 2010-04-16 Skapad: 2010-04-16 Senast uppdaterad: 2017-10-31
    2. Human Macrophages Infected with a High Burden of ESAT-6-Expressing M. tuberculosis Undergo Caspase-1-and Cathepsin B-Independent Necrosis
    Öppna denna publikation i ny flik eller fönster >>Human Macrophages Infected with a High Burden of ESAT-6-Expressing M. tuberculosis Undergo Caspase-1-and Cathepsin B-Independent Necrosis
    2011 (Engelska)Ingår i: PLOS ONE, ISSN 1932-6203, Vol. 6, nr 5Artikel i tidskrift (Refereegranskat) Published
    Abstract [en]

    Mycobacterium tuberculosis (Mtb) infects lung macrophages, which instead of killing the pathogen can be manipulated by the bacilli, creating an environment suitable for intracellular replication and spread to adjacent cells. The role of host cell death during Mtb infection is debated because the bacilli have been shown to be both anti-apoptotic, keeping the host cell alive to avoid the antimicrobial effects of apoptosis, and pro-necrotic, killing the host macrophage to allow infection of neighboring cells. Since mycobacteria activate the NLRP3 inflammasome in macrophages, we investigated whether Mtb could induce one of the recently described inflammasome-linked cell death modes pyroptosis and pyronecrosis. These are mediated through caspase-1 and cathepsin-B, respectively. Human monocyte-derived macrophages were infected with virulent (H37Rv) Mtb at a multiplicity of infection (MOI) of 1 or 10. The higher MOI resulted in strongly enhanced release of IL-1 beta, while a low MOI gave no IL-1 beta response. The infected macrophages were collected and cell viability in terms of the integrity of DNA, mitochondria and the plasma membrane was determined. We found that infection with H37Rv at MOI 10, but not MOI 1, over two days led to extensive DNA fragmentation, loss of mitochondrial membrane potential, loss of plasma membrane integrity, and HMGB1 release. Although we observed plasma membrane permeabilization and IL-1 beta release from infected cells, the cell death induced by Mtb was not dependent on caspase-1 or cathepsin B. It was, however, dependent on mycobacterial expression of ESAT-6. We conclude that as virulent Mtb reaches a threshold number of bacilli inside the human macrophage, ESAT-6-dependent necrosis occurs, activating caspase-1 in the process.

    Ort, förlag, år, upplaga, sidor
    Public Library of Science (PLoS), 2011
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-68900 (URN)10.1371/journal.pone.0020302 (DOI)000291052200049 ()
    Anmärkning
    Original Publication: Amanda Welin, Daniel Eklund, Olle Stendahl and Maria Lerm, Human Macrophages Infected with a High Burden of ESAT-6-Expressing M. tuberculosis Undergo Caspase-1-and Cathepsin B-Independent Necrosis, 2011, PLOS ONE, (6), 5. http://dx.doi.org/10.1371/journal.pone.0020302 Licensee: Public Library of Science (PLoS) http://www.plos.org/Tillgänglig från: 2011-06-10 Skapad: 2011-06-10 Senast uppdaterad: 2013-11-14
    3. Vitamin D enhances IL-1β secretion and restricts growth of Mycobacterium tuberculosis in macrophages from TB patients
    Öppna denna publikation i ny flik eller fönster >>Vitamin D enhances IL-1β secretion and restricts growth of Mycobacterium tuberculosis in macrophages from TB patients
    Visa övriga...
    2013 (Engelska)Ingår i: International Journal of Mycobacteriology, ISSN 2212-5531, Vol. 2, nr 1, s. 18-25Artikel i tidskrift (Refereegranskat) Published
    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.

    Ort, förlag, år, upplaga, sidor
    Netherlands: Elsevier, 2013
    Nyckelord
    Vitamin D, Human macrophages, Intracellular growth, TB patients, IL-1β
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-90356 (URN)10.1016/j.ijmyco.2012.11.001 (DOI)
    Tillgänglig från: 2013-03-25 Skapad: 2013-03-25 Senast uppdaterad: 2018-03-26
    4. Apoptotic neutrophils augment the inflammatory response to Mycobacterium tuberculosis infection in human macrophages
    Öppna denna publikation i ny flik eller fönster >>Apoptotic neutrophils augment the inflammatory response to Mycobacterium tuberculosis infection in human macrophages
    Visa övriga...
    2014 (Engelska)Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 7, s. e101514-Artikel i tidskrift (Refereegranskat) Published
    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.

    Ort, förlag, år, upplaga, sidor
    PLoS, 2014
    Nationell ämneskategori
    Medicin och hälsovetenskap
    Identifikatorer
    urn:nbn:se:liu:diva-100888 (URN)10.1371/journal.pone.0101514 (DOI)000338637300054 ()
    Tillgänglig från: 2013-11-14 Skapad: 2013-11-14 Senast uppdaterad: 2017-12-06Bibliografiskt granskad
    5. Human gene variants linked to enhanced NLRP3 activity limit intramacrophage growth of Mycobacterium tuberculosis
    Öppna denna publikation i ny flik eller fönster >>Human gene variants linked to enhanced NLRP3 activity limit intramacrophage growth of Mycobacterium tuberculosis
    Visa övriga...
    2014 (Engelska)Ingår i: The Journal of infectious diseases, ISSN 1537-6613, Vol. 209, nr 5, s. 749-753Artikel i tidskrift (Refereegranskat) Published
    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.

    Ort, förlag, år, upplaga, sidor
    University of Chicago Press / Oxford University Press (OUP), 2014
    Nationell ämneskategori
    Klinisk medicin
    Identifikatorer
    urn:nbn:se:liu:diva-100889 (URN)10.1093/infdis/jit572 (DOI)000331873700016 ()24158955 (PubMedID)
    Tillgänglig från: 2013-11-14 Skapad: 2013-11-14 Senast uppdaterad: 2015-04-10Bibliografiskt granskad
  • 4.
    Eklund, Daniel
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Persson, Hans Lennart
    Linköpings universitet, Institutionen för medicin och hälsa, Lungmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Centrum för kirurgi, ortopedi och cancervård, Lungmedicinska kliniken US.
    Larsson, Marie C.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Klinisk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Welin, Amanda
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Idh, Jonna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Paues, Jakob
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Infektionsmedicin. Linköpings universitet, Hälsouniversitetet.
    Fransson, Sven-Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Schön, Thomas
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Vitamin D enhances IL-1β secretion and restricts growth of Mycobacterium tuberculosis in macrophages from TB patients2013Ingår i: International Journal of Mycobacteriology, ISSN 2212-5531, Vol. 2, nr 1, s. 18-25Artikel i tidskrift (Refereegranskat)
    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.

  • 5.
    Eklund, Daniel
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Welin, Amanda
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Andersson, Henrik
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Verma, Deepti
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för inflammationsmedicin. Linköpings universitet, Hälsouniversitetet.
    Söderkvist, Peter
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Diagnostikcentrum, Klinisk patologi och klinisk genetik.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Särndahl, Eva
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Human gene variants linked to enhanced NLRP3 activity limit intramacrophage growth of Mycobacterium tuberculosis2014Ingår i: The Journal of infectious diseases, ISSN 1537-6613, Vol. 209, nr 5, s. 749-753Artikel i tidskrift (Refereegranskat)
    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.

  • 6.
    Eklund, Daniel
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Welin, Amanda
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    A medium-throughput microplate-based ex vivo model for measuring intramacrophage growth of mycobacterium tuberculosis in CYTOKINE, vol 48, issue 1-2, pp 14-142009Ingår i: CYTOKINE, 2009, Vol. 48, nr 1-2, s. 14-14Konferensbidrag (Refereegranskat)
    Abstract [en]

    n/a

  • 7.
    Eklund, Daniel
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Welin, Amanda
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Schon, Thomas
    Kalmar County Hospital.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Huygen, Kris
    Science Institute for Public Health, Belgium .
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Validation of a Medium-Throughput Method for Evaluation of Intracellular Growth of Mycobacterium tuberculosis2010Ingår i: Clinical and Vaccine Immunology, ISSN 1556-6811, E-ISSN 1556-679X, Vol. 17, nr 4, s. 513-517Artikel i tidskrift (Refereegranskat)
    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.

  • 8.
    Gustafsson, Mika
    et al.
    Linköpings universitet, Institutionen för fysik, kemi och biologi, Bioinformatik. Linköpings universitet, Tekniska fakulteten.
    Gawel, Danuta
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten.
    Alfredsson, Lars
    Karolinska Institute, Sweden.
    Baranzini, Sergio
    University of Calif San Francisco, CA, USA.
    Bjorkander, Janne
    County Council Jonköping, Sweden.
    Blomgran, Robert
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Medicinska fakulteten.
    Hellberg, Sandra
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten.
    Ernerudh, Jan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Diagnostikcentrum, Klinisk immunologi och transfusionsmedicin.
    Kockum, Ingrid
    Karolinska Institute, Sweden; Centre Molecular Med, Sweden.
    Konstantinell, Aelita
    Linköpings universitet, Medicinska fakulteten. Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Arctic University of Norway, Norway.
    Lahesmaa, Riita
    University of Turku, Finland; Abo Akad University, Finland.
    Lentini, Antonio
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten.
    Liljenström, H. Robert I.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten.
    Mattson, Lina
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten.
    Matussek, Andreas
    County Council Jonköping, Sweden.
    Mellergård, Johan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för neuro- och inflammationsvetenskap. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Närsjukvården i centrala Östergötland, Neurologiska kliniken.
    Mendez, Melissa
    University of Peruana Cayetano Heredia, Peru.
    Olsson, Tomas
    Karolinska Institute, Sweden; Centre Molecular Med, Sweden.
    Pujana, Miguel A.
    Catalan Institute Oncol, Spain.
    Rasool, Omid
    University of Turku, Finland; Abo Akad University, Finland.
    Serra-Musach, Jordi
    Catalan Institute Oncol, Spain.
    Stenmarker, Margaretha
    County Council Jonköping, Sweden.
    Tripathi, Subhash
    University of Turku, Finland; Abo Akad University, Finland.
    Viitala, Miro
    University of Turku, Finland; Abo Akad University, Finland.
    Wang, Hui
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten. University of Texas MD Anderson Cancer Centre, TX 77030 USA.
    Zhang, Huan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten.
    Nestor, Colm
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten.
    Benson, Mikael
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Medicinska fakulteten. Region Östergötland, Hjärt- och Medicincentrum, Allergicentrum US.
    A validated gene regulatory network and GWAS identifies early regulators of T cell-associated diseases2015Ingår i: Science Translational Medicine, ISSN 1946-6234, E-ISSN 1946-6242, Vol. 7, nr 313, artikel-id 313ra178Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Early regulators of disease may increase understanding of disease mechanisms and serve as markers for presymptomatic diagnosis and treatment. However, early regulators are difficult to identify because patients generally present after they are symptomatic. We hypothesized that early regulators of T cell-associated diseases could be found by identifying upstream transcription factors (TFs) in T cell differentiation and by prioritizing hub TFs that were enriched for disease-associated polymorphisms. A gene regulatory network (GRN) was constructed by time series profiling of the transcriptomes and methylomes of human CD4(+) T cells during in vitro differentiation into four helper T cell lineages, in combination with sequence-based TF binding predictions. The TFs GATA3, MAF, and MYB were identified as early regulators and validated by ChIP-seq (chromatin immunoprecipitation sequencing) and small interfering RNA knockdowns. Differential mRNA expression of the TFs and their targets in T cell-associated diseases supports their clinical relevance. To directly test if the TFs were altered early in disease, T cells from patients with two T cell-mediated diseases, multiple sclerosis and seasonal allergic rhinitis, were analyzed. Strikingly, the TFs were differentially expressed during asymptomatic stages of both diseases, whereas their targets showed altered expression during symptomatic stages. This analytical strategy to identify early regulators of disease by combining GRNs with genome-wide association studies may be generally applicable for functional and clinical studies of early disease development.

  • 9.
    Idh, Jonna
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Raffetseder, Johanna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Larsson, Marie
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Klinisk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Pienaar, Elsje
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Forslund, Tony
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    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
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    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 MacrophagesManuskript (preprint) (Övrigt vetenskapligt)
    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.

  • 10.
    Kempe, Per
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Hälsouniversitetet. Department of Obstetrics & Gynaecology, County Hospital Sundsvall, Sweden.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för inflammationsmedicin. Linköpings universitet, Hälsouniversitetet.
    Hallin, Agnes
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Hammar, Mats
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Barn- och kvinnocentrum, Kvinnokliniken i Linköping.
    Olsson, Thomas
    Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Brynhildsen, Jan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Barn- och kvinnocentrum, Kvinnokliniken i Linköping.
    Ernerudh, Jan
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för inflammationsmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Diagnostikcentrum, Klinisk immunologi och transfusionsmedicin.
    T cell subset-associated transcription factors, cytokines and chemokines in relation to the menstrual cycle and use of combined hormonal contraceptives in women with multiple sclerosis and healthy controls2014Manuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Study question: Do peripheral blood levels of cytokines, chemokines, and transcription factors for different T helper (Th) cell subsets change in relation to high and low estrogen/progestogen states in women with multiple sclerosis (MS) and healthy controls with and without combined hormonal contraceptives (CHC)?

    Summary answer: Our findings indicate a general activation of peripheral blood T cells and B cells during high estrogen/progestogen phases with higher levels of transcription factors associated with both Th1 (TBX21) and Th2 (GATA3) subsets of T cells and the B cell-associated chemokine CXCL13.

    What is known already: There are some indications that sex steroids may positively affect MS clinically and immunologically.

    Study design, size, duration: A total of 60 women were included. Paired blood samples were drawn in high and low estrogen/progestogen phases during the same cycle in women using or not using CHC.

    Participants/materials, setting, methods: Participants were female MS patients and healthy controls with and without CHC. Concentrations of cytokines and chemokines were measured using multiplex bead technology and expression of transcription factors in blood cells was determined by qPCR. Owing to possible differences in cell composition, expression of Th-associated transcription factors were normalized to the T cell-specific transcription factor CD3E.

    Main results and the role of chance: Sixty women were included but 13 women dropped out, leaving 47 women to the statistical analyses. In healthy controls using CHC, both TBX21, and GATA3 expression was higher in the high estrogen/progestogen phase than in the low estrogen/progestogen phase. TBX21 expression in high estrogen/progestogen phase differed significantly between groups with the highest levels in healthy controls without CHC. In all MS patients as well as in healthy controls using CHC, the concentrations of CXCL13 was significantly higher in the high estrogen/progestogen phase compared to the low estrogen/progestogen phase.

    Limitations, reasons for caution: The low number of participants. A majority of the MS patients were using immunomodulatory drugs which may have interfered with the results. The study design makes it impossible to differ between estrogenic and progestogenic effects.

    Wider implications of the findings: Our findings show that high and low levels of estrogens and/or progestogens differently affect immune parameters related to Th cell subsets as well as B cells. The differences between high- and low estrogen/progestogen phases were most obvious in women using CHC indicating that CHC is more potent than 17β-Estradiol/progesterone in inducing immune changes in both MS patients and healthy women.

    Study funding/competing interest(s): This study was funded by the County Councils of Östergötland and Västernorrland, Sweden. No author have any conflicts of interest to declare.

  • 11.
    Persson, Alexander
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Blomgran, Robert
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Lundstrom, Charlotte
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Induction of apoptosis in human neutrophils by Mycobacterium tuberculosis is dependent on mature bacterial lipoproteins2009Ingår i: Microbial Pathogenesis, ISSN 0882-4010, E-ISSN 1096-1208, Vol. 47, nr 3, s. 143-150Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Modulation of immune cell apoptosis is a key evasion strategy utilized by Mycobacterium tuberculosis (Mtb). To be able to multiply within macrophages, the bacterium delays apoptosis and down-regulates pro-inflammatory activation in these cells, whereas apoptosis is rapidly induced in the potently bactericidal neutrophils. Initial host-pathogen interactions between neutrophils and Mtb, subsequently leading to apoptosis, need to be investigated to understand the early features during Mtb infections. Opsonized Mtb were readily phagocytosed, and the immuno-mediated phagocytosis triggered early activation of anti-apoptotic Akt in the neutrophils but the bacteria still induced apoptosis to the same extent as non-phagocytosed Mtb. Mtb-induced apoptosis was strictly dependent on NADPH oxidase-generated reactive oxygen species, compounds shown to damage lysosomal granules. Despite this, we found no involvement of damaged azurophilic granules in Mtb-induced apoptosis in human neutrophils. Instead, the Mtb-induced apoptosis was p38 MAPK dependent and induced through the mitochondrial pathway. Moreover, Mtb deficient of mature lipoproteins lacked the determinants required for induction of neutrophil apoptosis. These results show that Mtb exert a strong intrinsic capacity to induce apoptosis in neutrophils that is capable of overcoming the anti-apoptotic signaling in the cell.

  • 12.
    Persson, Hans Lennart
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa, Lungmedicin. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Centrum för kirurgi, ortopedi och cancervård, Lungmedicinska kliniken US.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Welin, Amanda
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Paues, Jakob
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Infektionsmedicin. Linköpings universitet, Hälsouniversitetet.
    Idh, Jonna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Fransson, Sven-Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Schön, Thomas
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Alveolar macrophages from patients with tuberculosis exhibit reduced capacity of restricting growth of Mycobacterium tuberculosis: a pilot study of vitamin D stimulation in vitro2013Ingår i: HOAJ Biology, ISSN 2050-0874Artikel i tidskrift (Refereegranskat)
    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.

  • 13.
    Persson, Hans Lennart
    et al.
    Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Hälsouniversitetet.
    Jacobson, Petra
    Linköpings universitet, Institutionen för medicin och hälsa. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin. Linköpings universitet, Hälsouniversitetet.
    Larsson, Marie C.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Klinisk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Welin, Amanda
    Göteborgs universitet.
    Paues, Jakob
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Cellbiologi. Linköpings universitet, Hälsouniversitetet.
    Idh, Jonna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Fransson, Sven-Göran
    Linköpings universitet, Institutionen för medicin och hälsa, Medicinsk radiologi. Linköpings universitet, Hälsouniversitetet. Östergötlands Läns Landsting, Diagnostikcentrum, Röntgenkliniken i Linköping.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Schon, Thomas
    Kalmar länssjukhus.
    Alveolar macrophages from patients with tuberculosis display a reduced capacity to inhibit growth of Mycomacterium tuberculosis2012Konferensbidrag (Övrigt vetenskapligt)
  • 14.
    Raffetseder, Johanna
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Pienaar, Elsje
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Blomgran, Robert
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för inflammationsmedicin. Linköpings universitet, Hälsouniversitetet.
    Brodin Patcha, Veronika
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för kliniska vetenskaper. Linköpings universitet, Hälsouniversitetet.
    Andersson, Henrik
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Welin, Amanda
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Avdelningen för mikrobiologi och molekylär medicin. Linköpings universitet, Hälsouniversitetet.
    Replication Rates of Mycobacterium tuberculosis in Human Macrophages Do Not Correlate with Mycobacterial Antibiotic Susceptibility2014Ingår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, nr 11, s. e112426-Artikel i tidskrift (Refereegranskat)
    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.

  • 15.
    Welin, Amanda
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Hälsouniversitetet. Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Human Macrophages Infected with a High Burden of ESAT-6-Expressing M. tuberculosis Undergo Caspase-1-and Cathepsin B-Independent Necrosis2011Ingår i: PLOS ONE, ISSN 1932-6203, Vol. 6, nr 5Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Mycobacterium tuberculosis (Mtb) infects lung macrophages, which instead of killing the pathogen can be manipulated by the bacilli, creating an environment suitable for intracellular replication and spread to adjacent cells. The role of host cell death during Mtb infection is debated because the bacilli have been shown to be both anti-apoptotic, keeping the host cell alive to avoid the antimicrobial effects of apoptosis, and pro-necrotic, killing the host macrophage to allow infection of neighboring cells. Since mycobacteria activate the NLRP3 inflammasome in macrophages, we investigated whether Mtb could induce one of the recently described inflammasome-linked cell death modes pyroptosis and pyronecrosis. These are mediated through caspase-1 and cathepsin-B, respectively. Human monocyte-derived macrophages were infected with virulent (H37Rv) Mtb at a multiplicity of infection (MOI) of 1 or 10. The higher MOI resulted in strongly enhanced release of IL-1 beta, while a low MOI gave no IL-1 beta response. The infected macrophages were collected and cell viability in terms of the integrity of DNA, mitochondria and the plasma membrane was determined. We found that infection with H37Rv at MOI 10, but not MOI 1, over two days led to extensive DNA fragmentation, loss of mitochondrial membrane potential, loss of plasma membrane integrity, and HMGB1 release. Although we observed plasma membrane permeabilization and IL-1 beta release from infected cells, the cell death induced by Mtb was not dependent on caspase-1 or cathepsin B. It was, however, dependent on mycobacterial expression of ESAT-6. We conclude that as virulent Mtb reaches a threshold number of bacilli inside the human macrophage, ESAT-6-dependent necrosis occurs, activating caspase-1 in the process.

  • 16.
    Welin, Amanda
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Human macrophages infected with virulent Mycobacterium tuberculosis undergo ESAT-6-dependent necrosis, but not pyroptosis or pyronecrosisManuskript (preprint) (Övrigt vetenskapligt)
    Abstract [en]

    Mycobacterium tuberculosis (Mtb) infects lung macrophages, which instead of killing the pathogen can be manipulated by the bacilli, creating an environment suitable for intracellular replication and spread to adjacent cells. The role of host cell death during Mtb infection is debated because the bacilli have been shown to be both anti-apoptotic, keeping the host cell alive to avoid the antimicrobial effects of apoptosis, and pro-necrotic, killing the host macrophage to allow infection of neighboring cells. Since mycobacteria are able to activate the NLRP3 inflammasome, we investigated whether Mtb could induce one of the recently described inflammasome-linked cell death modes pyroptosis and pyronecrosis, in human monocyte-derived macrophages. Cells were infected with virulent (H37Rv) Mtb at a multiplicity of infection (MOI) of 1 or 10. The higher MOI resulted in strongly enhanced release of IL-1β, while a low MOI gave no IL-1β response. The infected macrophages were collected and cell viability in terms of the integrity of DNA, mitochondria and the plasma membrane was determined. We found that infection with H37Rv at MOI 10, but not MOI 1, over two days led to extensive DNA fragmentation, loss of mitochondrial membrane potential and loss of plasma membrane integrity. Although we observed plasma membrane permeabilization and IL-1 β release from infected cells, the cell death induced by Mtb was not pyroptosis or pyronecrosis, as it was independent of caspase-1 and cathepsin B. Instead, we conclude that as virulent Mtb reaches a threshold number of bacilli inside the macrophage, ESAT-6-dependent necrosis occurs, activating caspase-1 in the process.

  • 17.
    Welin, Amanda
    et al.
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Raffetseder, Johanna
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Eklund, Daniel
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Stendahl, Olle
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Lerm, Maria
    Linköpings universitet, Institutionen för klinisk och experimentell medicin, Medicinsk mikrobiologi. Linköpings universitet, Hälsouniversitetet.
    Importance of phagosomal functionality for growth restriction of Mycobacterium tuberculosis in primary human macrophages2011Ingår i: Journal of Innate Immunity, ISSN 1662-811X, E-ISSN 1662-8128, Vol. 3, nr 5, s. 508-518Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The best characterized survival mechanism of Mycobacterium tuberculosis inside the macrophage is the inhibition of phagosomal maturation. Phagosomal maturation involves several steps including fusion with lysosomes and acidification. However, it has not been elucidated which components of phagosomal maturation correlate with growth restriction of virulent mycobacteria in human macrophages, and we aimed to study this. We infected human monocyte-derived macrophages with M. tuberculosis and assessed bacterial replication, translocation of CD63 to the phagosome, and phagosomal acidification. We found that unstimulated macrophages were able to control infection with M. tuberculosis upon inoculation at a low, but not high, multiplicity of infection (MOI). H37Rv and H37Ra infection, at both high and low MOI, led to equally ineffective translocation of CD63 to the phagosome. This was true despite the impaired growth ability of H37Rv at the low MOI and of H37Ra even at the high MOI, indicating that inhibition of CD63 translocation was not sufficient for growth to occur. On the other hand, acidification of mycobacterial phagosomes was more efficient at a low MOI with both mycobacterial strains, consistent with a role for phagosomal acidification in restricting M. tuberculosis growth. Inhibition of the vacuolar H+-ATPase as well as of cathepsin D led to enhanced mycobacterial replication inside the macrophage. We conclude that acidification and related functional aspects of the mature phagosome are important factors for restriction of M. tuberculosis replication in human macrophages.

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