title: Systemic immunization with an epitope-based vaccine elicits a Th1-biased response and provides protection against Helicobacter pylori in mice.
abstract: Vaccine-mediated Th1-biased CD4+ T cell responses have been shown to be crucial for protection against Helicobacter pylori (H. pylori). In this study, we investigated whether a vaccine composed of CD4+ T cell epitopes together with Th1 adjuvants could confer protection against H. pylori in a mouse model. We constructed an epitope-based vaccine, designated Epivac, which was composed of predicted immunodominant CD4+ T cell epitopes from H. pylori adhesin A (HpaA), urease B (UreB) and cytotoxin-associated gene A product (CagA). Together with four different Th1 adjuvants, Epivac was administered subcutaneously and the prophylactic potential was examined. Compared to non-immunized mice, immunization with Epivac alone or with a Th1 adjuvant significantly reduced H. pylori colonization, and better protection was observed when an adjuvant was used. Immunized mice exhibited a strong local and systemic Th1-biased immune response, which may contribute to the inhibition of H. pylori colonization. Though a significant specific antibody response was induced by the vaccine, no correlation was found between the intensity of the humoral response and the protective effect. Our results suggest that a vaccine containing CD4+ T cell epitopes is a promising candidate for protection against H. pylori infection.
authors.affiliation: Department of Clinical Microbiology and Immunology, College of Medical Laboratory, Third Military Medical University, Chongqing 400038, China.
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Li
authors.forename: Jin-Yong
authors.initials: JY
authors.lastname: Zhang
authors.forename: Ya-Fei
authors.initials: YF
authors.lastname: He
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Bin
authors.initials: B
authors.lastname: Li
authors.forename: Kai-Yun
authors.initials: KY
authors.lastname: Liu
authors.forename: Wu-Chen
authors.initials: WC
authors.lastname: Yang
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Zhao
authors.forename: Quan-Ming
authors.initials: QM
authors.lastname: Zou
authors.forename: Chao
authors.initials: C
authors.lastname: Wu
mesh_terms: D000818:Animals; D001428:Bacterial Vaccines / Q000276:immunology* / Q000627:therapeutic use*; D000939:Epitopes / Q000276:immunology*; D005260:Female; D016481:Helicobacter Infections / Q000276:immunology* / Q000517:prevention & control*; D016480:Helicobacter pylori / Q000276:immunology* / Q000472:pathogenicity*; D007114:Immunization; D051379:Mice; D008807:Mice, Inbred BALB C
chemical_list: D001428:Bacterial Vaccines; D000939:Epitopes