title: A dominant CD4(+) T-cell response to Helicobacter pylori reduces risk for gastric disease in humans.
abstract: OBJECTIVE
  Immunodominance is an important feature of antiviral, antitumor, and antibacterial cellular immune responses, but it is not well demonstrated in the immune responses against Helicobacter pylori. Antigen-specific CD4(+) T cells protect mice against infection with H pylori. We investigated the immunodominant CD4(+) T-cell response to neuraminyllactose-binding hemagglutinin (HpaA), which is a conserved, H pylori-specific colonization factor that is being investigated as an antigen for vaccination strategies.
  
  
  METHODS
  HpaA-specific CD4(+) T cells were expanded with autologous peripheral blood mononuclear cells that had been incubated with recombinant HpaA and characterized using overlapping synthetic peptides. We compared the percentage of CD4(+) T cells with specificity for HpaA(88-100), restricted to HLA-DRB1*1501, among 59 H pylori-infected subjects with different gastric diseases.
  
  
  RESULTS
  We identified and characterized several immunodominant CD4(+) T-cell epitopes derived from HpaA. The immunodominant CD4(+) T-cell responses specific to HpaA(88-100) were observed in most H pylori-infected individuals who expressed HLA-DRB1*1501 and were significantly more abundant in patients with less severe diseases (P < .05).
  
  
  CONCLUSIONS
  The HLA-DRB1*1501-restricted immunodominant CD4(+) T-cell response to HpaA(88-100) is associated with reduced risk of severe gastric diseases. Further study of these and other immunodominant CD4(+) T-cell responses to H pylori will provide insight into mechanisms of protective immunity and aid in vaccine design.
authors.affiliation: Department of Clinical Microbiology and Immunology, College of Medical Laboratory Science, Third Military Medical University, Chongqing, China.
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Wu-Chen
authors.initials: WC
authors.lastname: Yang
authors.forename: Jia-Lin
authors.initials: JL
authors.lastname: He
authors.forename: Ning-Yi
authors.initials: NY
authors.lastname: Li
authors.forename: Jian
authors.initials: J
authors.lastname: Hu
authors.forename: Ya-Fei
authors.initials: YF
authors.lastname: He
authors.forename: Shu
authors.initials: S
authors.lastname: Yu
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Zhao
authors.forename: Ping
authors.initials: P
authors.lastname: Luo
authors.forename: Jin-Yong
authors.initials: JY
authors.lastname: Zhang
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Li
authors.forename: Ming
authors.initials: M
authors.lastname: Zeng
authors.forename: Dong-Shui
authors.initials: DS
authors.lastname: Lu
authors.forename: Bo-Sheng
authors.initials: BS
authors.lastname: Li
authors.forename: Hong
authors.initials: H
authors.lastname: Guo
authors.forename: Shi-Ming
authors.initials: SM
authors.lastname: Yang
authors.forename: Gang
authors.initials: G
authors.lastname: Guo
authors.forename: Xu-Hu
authors.initials: XH
authors.lastname: Mao
authors.forename: Weisan
authors.initials: W
authors.lastname: Chen
authors.forename: Chao
authors.initials: C
authors.lastname: Wu
authors.forename: Quan-Ming
authors.initials: QM
authors.lastname: Zou
mesh_terms: D001426:Bacterial Proteins / Q000276:immunology; D001428:Bacterial Vaccines / Q000276:immunology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018984:Epitopes, T-Lymphocyte / Q000276:immunology; D059811:HLA-DRB1 Chains / Q000276:immunology; D016481:Helicobacter Infections / Q000276:immunology*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D037102:Lectins / Q000276:immunology; D008074:Lipoproteins / Q000276:immunology; D012306:Risk; D013272:Stomach Diseases / Q000453:epidemiology* / Q000382:microbiology* / Q000517:prevention & control
chemical_list: D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D018984:Epitopes, T-Lymphocyte; D059811:HLA-DRB1 Chains; C489631:HLA-DRB1*15:01 antigen; C096437:HpaA protein, bacteria; D037102:Lectins; D008074:Lipoproteins