title: Natural Killer Cells Mediate Protection against Yersinia pseudotuberculosis in the Mesenteric Lymph Nodes.
abstract: Natural killer cells play a crucial role in the initial defense against bacterial pathogens. The crosstalk between host cells infected with intracellular pathogens and NK cells has been studied intensively, but not much attention has been given to characterize the role of NK cells in the response to extracellular bacterial pathogens such as yersiniae. In this study we used antibody-mediated NK cell depletion to address the importance of this immune cell type in controlling a Y. pseudotuberculosis infection. Analysis of the bacterial counts was used to follow the infection and flow cytometry was performed to characterize the composition and dynamic of immune cells. Depletion of NK cells led to higher bacterial loads within the mesenteric lymph nodes. We further show that in particular CD11b+ CD27+ NK cells which express higher levels of the activation marker CD69 increase within the mesenteric lymph nodes during a Y. pseudotuberculosis infection. Moreover, in response to the activation NK cells secrete higher levels of IFNy, which in turn triggers the production of the proinflammatory cytokine TNFα. These results suggest, that NK cells aid in the clearance of Y. pseudotuberculosis infections mainly by triggering the expression of proinflammatory cytokines manipulating the host immune response.
authors: Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors: Maik
authors: M
authors: Rosenheinrich
authors: Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors: Wiebke
authors: W
authors: Heine
authors: Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors: Carina M
authors: CM
authors: Schmühl
authors: Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors: Fabio
authors: F
authors: Pisano
authors: Department of Molecular Infection Biology, Helmholtz Centre for Infection Research, Braunschweig, Germany.
authors: Petra
authors: P
authors: Dersch
mesh_terms: D000818:Animals; D000906:Antibodies / Q000494:pharmacology; D015703:Antigens, CD / Q000235:genetics / Q000276:immunology; D001402:B-Lymphocytes / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D005260:Female; D015870:Gene Expression; D016130:Immunophenotyping; D007371:Interferon-gamma / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D007694:Killer Cells, Natural / Q000187:drug effects / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D008198:Lymph Nodes / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D018655:Lymphocyte Count; D008212:Lymphocyte Depletion; D008264:Macrophages / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D008643:Mesentery / Q000276:immunology* / Q000382:microbiology / Q000473:pathology; D051379:Mice; D008810:Mice, Inbred C57BL; D009504:Neutrophils / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D013154:Spleen / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000382:microbiology / Q000473:pathology; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000276:immunology / Q000378:metabolism; D015011:Yersinia pseudotuberculosis / Q000276:immunology*; D015012:Yersinia pseudotuberculosis Infections / Q000276:immunology* / Q000382:microbiology / Q000473:pathology
chemical_list: D000906:Antibodies; D015703:Antigens, CD; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma