title: Resistance of primary murine CD4+ T cells to Helicobacter pylori vacuolating cytotoxin.
abstract: Persistent colonization of the human stomach by Helicobacter pylori is a risk factor for the development of gastric cancer and peptic ulcer disease. H. pylori secretes a toxin, VacA, that targets human gastric epithelial cells and T lymphocytes and enhances the ability of H. pylori to colonize the stomach in a mouse model. To examine how VacA contributes to H. pylori colonization of the mouse stomach, we investigated whether murine T lymphocytes were susceptible to VacA activity. VacA inhibited interleukin-2 (IL-2) production by a murine T-cell line (LBRM-33), similar to its effects on a human T-cell line (Jurkat), but did not inhibit IL-2 production by primary murine splenocytes or CD4+ T cells. VacA inhibited activation-induced proliferation of primary human CD4+ T cells but did not inhibit the proliferation of primary murine CD4+ T cells. Flow cytometry studies indicated that the levels of VacA binding to primary murine CD4+ T cells were significantly lower than levels of VacA binding to human CD4+ T cells. This suggests that the resistance of primary murine CD4+ T cells to VacA is attributable, at least in part, to impaired VacA binding to these cells.
authors.affiliation: Departments of Medicine, Vanderbilt University School of Medicine, Nashville, TN 37232, USA.
authors.forename: Holly M Scott
authors.initials: HM
authors.lastname: Algood
authors.forename: Victor J
authors.initials: VJ
authors.lastname: Torres
authors.forename: Derya
authors.initials: D
authors.lastname: Unutmaz
authors.forename: Timothy L
authors.initials: TL
authors.lastname: Cover
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000276:immunology* / Q000378:metabolism; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology* / Q000378:metabolism; D049109:Cell Proliferation; D002478:Cells, Cultured; D005434:Flow Cytometry; D016481:Helicobacter Infections / Q000276:immunology / Q000378:metabolism; D016480:Helicobacter pylori / Q000276:immunology* / Q000472:pathogenicity*; D006801:Humans; D015151:Immunoblotting; D007376:Interleukin-2 / Q000096:biosynthesis; D019169:Jurkat Cells; D008213:Lymphocyte Activation / Q000276:immunology; D051379:Mice; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D007376:Interleukin-2; C074689:VacA protein, Helicobacter pylori; D048051:p38 Mitogen-Activated Protein Kinases