title: Identification of two novel immunodominant UreB CD4(+) T cell epitopes in Helicobacter pylori infected subjects.
abstract: An epitope-based vaccine is a promising option for treating Helicobacter pylori (H. pylori) infection. Epitope mapping is the first step in designing an epitope-based vaccine. A pivotal role of CD4(+) T cells in protection against H. pylori has been accepted, but few Th epitopes have been identified. In this study, two novel UreB CD4(+) T cell epitopes were identified using PBMCs obtained from two H. pylori infected subjects. We determined the restriction molecules by antibody blocking and used various Epstein-Barr virus-transformed B lymphocyte cell lines (BLCLs) with different HLA alleles as APCs to present peptides to CD4(+) T cells. These epitopes were DRB1*1404-restricted UreB(373-385) and DRB1*0803-restricted UreB(438-452). The T cells specific to these epitopes not only recognized autologous DCs loaded with recombinant UreB but also those pulsed with H. pylori whole cell lysates, suggesting that these epitope peptides are naturally processed. These epitopes have important value for designing an effective H. pylori vaccine.
authors.affiliation: Department of Clinical Microbiology and Immunology, College of Medical Laboratory Science, Third Military Medical University, Chongqing 400038, PR China.
authors.forename: Wu-Chen
authors.initials: WC
authors.lastname: Yang
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Li
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Jian
authors.initials: J
authors.lastname: Hu
authors.forename: Jin-Yong
authors.initials: JY
authors.lastname: Zhang
authors.forename: Shi-Ming
authors.initials: SM
authors.lastname: Yang
authors.forename: Quan-Ming
authors.initials: QM
authors.lastname: Zou
authors.forename: Hong
authors.initials: H
authors.lastname: Guo
authors.forename: Chao
authors.initials: C
authors.lastname: Wu
mesh_terms: D000942:Antigens, Bacterial / Q000276:immunology*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology*; D018604:Epitope Mapping; D018984:Epitopes, T-Lymphocyte / Q000276:immunology*; D059811:HLA-DRB1 Chains / Q000276:immunology; D016481:Helicobacter Infections / Q000276:immunology*; D016480:Helicobacter pylori / Q000276:immunology*; D006801:Humans; D014510:Urease / Q000276:immunology*
chemical_list: D000942:Antigens, Bacterial; D018984:Epitopes, T-Lymphocyte; D059811:HLA-DRB1 Chains; D014510:Urease