title: Potential role of CagA in the inhibition of T cell reactivity in Helicobacter pylori infections.
abstract: The pathogenicity of chronic gastroduodenal diseases is very often related to Helicobacter pylori infections. Most H. pylori strains carry the cagA gene encoding an immunodominant 120- to 128-kDa protein which is considered a virulence marker. The majority of CagA-positive H. pylori isolates also produce a 95-kDa protein cytotoxin (VacA) causing vacuolation and degradation of mammalian cells. In our previous study we have shown that live H. pylori bacteria and their sonicates inhibit PHA-driven proliferation of human T lymphocytes. The H. pylori CagA and VacA proteins were suspected of a paralyzing effect of H. pylori on T cell proliferation. In this report, by using isogenic H. pylori mutant strains defective in CagA and VacA proteins, we determined that CagA is responsible for the inhibition of PHA-induced proliferation of T cells.
authors.affiliation: Department of Infectious Biology, University of Lodz, Lodz, 90-237, Poland.
authors.forename: B
authors.initials: B
authors.lastname: Paziak-Domańska
authors.forename: M
authors.initials: M
authors.lastname: Chmiela
authors.forename: A
authors.initials: A
authors.lastname: Jarosińska
authors.forename: W
authors.initials: W
authors.lastname: Rudnicka
mesh_terms: D000942:Antigens, Bacterial / Q000235:genetics / Q000276:immunology*; D001426:Bacterial Proteins / Q000235:genetics / Q000276:immunology*; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D003603:Cytotoxins / Q000235:genetics / Q000276:immunology; D016480:Helicobacter pylori / Q000235:genetics / Q000276:immunology* / Q000502:physiology; D006801:Humans; D010835:Phytohemagglutinins / Q000494:pharmacology; D013601:T-Lymphocytes / Q000166:cytology / Q000187:drug effects / Q000276:immunology* / Q000382:microbiology
chemical_list: D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D003603:Cytotoxins; D010835:Phytohemagglutinins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori