Potential role of CagA in the inhibition of T cell reactivity in Helicobacter pylori infections.
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.
Paziak-Domańska
B
B
Department of Infectious Biology, University of Lodz, Lodz, 90-237, Poland.
Chmiela
M
M
Jarosińska
A
A
Rudnicka
W
W
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
D000942:Antigens, Bacterial; D001426:Bacterial Proteins; D003603:Cytotoxins; D010835:Phytohemagglutinins; C074689:VacA protein, Helicobacter pylori; C080866:cagA protein, Helicobacter pylori