title: Induction of CD69 expression by cagPAI-positive Helicobacter pylori infection.
abstract: OBJECTIVE
  To investigate and elucidate the molecular mechanism that regulates inducible expression of CD69 by Helicobacter pylori (H. pylori) infection.
  
  
  METHODS
  The expression levels of CD69 in a T-cell line, Jurkat, primary human peripheral blood mononuclear cells (PBMCs), and CD4+ T cells, were assessed by immunohistochemistry, reverse transcription polymerase chain reaction, and flow cytometry. Activation of CD69 promoter was detected by reporter gene. Nuclear factor (NF)-κB activation in Jurkat cells infected with H. pylori was evaluated by electrophoretic mobility shift assay. The role of NF-κB signaling in H. pylori-induced CD69 expression was analyzed using inhibitors of NF-κB and dominant-negative mutants. The isogenic mutants with disrupted cag pathogenicity island (cagPAI) and virD4 were used to elucidate the role of cagPAI-encoding type IV secretion system and CagA in CD69 expression.
  
  
  RESULTS
  CD69 staining was detected in mucosal lymphocytes and macrophages in specimens of patients with H. pylori-positive gastritis. Although cagPAI-positive H. pylori and an isogenic mutant of virD4 induced CD69 expression, an isogenic mutant of cagPAI failed to induce this in Jurkat cells. H. pylori also induced CD69 expression in PBMCs and CD4+ T cells. The activation of the CD69 promoter by H. pylori was mediated through NF-κB. Transfection of dominant-negative mutants of IκBs, IκB kinases, and NF-κB-inducing kinase inhibited H. pylori-induced CD69 activation. Inhibitors of NF-κB suppressed H. pylori-induced CD69 mRNA expression.
  
  
  CONCLUSIONS
  The results suggest that H. pylori induces CD69 expression through the activation of NF-κB. cagPAI might be relevant in the induction of CD69 expression in T cells. CD69 in T cells may play a role in H. pylori-induced gastritis.
authors: Department of Microbiology and Oncology, Graduate School of Medicine, University of the Ryukyus, Nishihara, Okinawa 903-0215, Japan. naokimori50@gmail.com
authors: Naoki
authors: N
authors: Mori
authors: Chie
authors: C
authors: Ishikawa
authors: Masachika
authors: M
authors: Senba
mesh_terms: D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics / Q000378:metabolism*; D015703:Antigens, CD / Q000235:genetics / Q000378:metabolism*; D000945:Antigens, Differentiation, T-Lymphocyte / Q000235:genetics / Q000378:metabolism*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D016481:Helicobacter Infections / Q000378:metabolism*; D016480:Helicobacter pylori / Q000378:metabolism / Q000472:pathogenicity; D006801:Humans; D019169:Jurkat Cells; D037181:Lectins, C-Type / Q000235:genetics / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D011401:Promoter Regions, Genetic; D000099192:CD69 Antigens
chemical_list: D000942:Antigens, Bacterial; D015703:Antigens, CD; D000945:Antigens, Differentiation, T-Lymphocyte; D001426:Bacterial Proteins; D037181:Lectins, C-Type; D016328:NF-kappa B; D000099192:CD69 Antigens; C080866:cagA protein, Helicobacter pylori