Immunological features and efficacy of a multi-epitope vaccine CTB-UE against H. pylori in BALB/c mice model

Appl Microbiol Biotechnol. 2014 Apr;98(8):3495-507. doi: 10.1007/s00253-013-5408-6. Epub 2013 Dec 28.

Abstract

Epitope vaccine is a promising option for prophylactic and therapeutic vaccination against Helicobacter pylori infection. Urease is an essential virulence factor and colonization factor for H. pylori. In this study, we constructed a multi-epitope vaccine named CTB-UE with mucosal adjuvant cholera toxin B subunit (CTB) and tandem copies of Th and B cell epitopes from H. pylori urease A and B subunits. The immunogenicity, specificity, ability to induce neutralizing antibodies against H. pylori urease, and prophylactic and therapeutic efficacy of the CTB-UE vaccine were evaluated in BALB/c mice model after purification. The experimental results indicated that CTB-UE could induce comparatively high levels of specific antibodies against native H. pylori urease, UreA, UreB, or the selected B cell epitopes UreA₁₈₃₋₂₀₃ and UreB₃₂₇₋₃₃₄ involved with the active site of urease and showed an effectively inhibitory effect on the enzymatic activity of urease. Besides, oral prophylactic or therapeutic immunization with CTB-UE significantly decreased H. pylori colonization compared with oral immunization with rUreB or PBS, and the protection was correlated with antigen-specific CD4⁺ T cells and IgG, IgA, and mucosal sIgA antibody responses. This CTB-UE vaccine may be a promising vaccine candidate for the control of H. pylori infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic / administration & dosage
  • Administration, Oral
  • Animals
  • Antibodies, Bacterial / blood
  • Bacterial Load
  • Bacterial Vaccines / administration & dosage
  • Bacterial Vaccines / genetics
  • Bacterial Vaccines / immunology*
  • CD4-Positive T-Lymphocytes / immunology
  • Cholera Toxin / administration & dosage
  • Disease Models, Animal
  • Epitopes, B-Lymphocyte / genetics
  • Epitopes, B-Lymphocyte / immunology*
  • Epitopes, T-Lymphocyte / genetics
  • Epitopes, T-Lymphocyte / immunology*
  • Helicobacter pylori / genetics
  • Helicobacter pylori / immunology*
  • Immunity, Mucosal
  • Immunoglobulin A / analysis
  • Immunoglobulin A / blood
  • Immunoglobulin A, Secretory
  • Immunoglobulin G / blood
  • Mice
  • Mice, Inbred BALB C
  • Stomach / microbiology
  • Urease / genetics
  • Urease / immunology*
  • Vaccines, Synthetic / administration & dosage
  • Vaccines, Synthetic / genetics
  • Vaccines, Synthetic / immunology

Substances

  • Adjuvants, Immunologic
  • Antibodies, Bacterial
  • Bacterial Vaccines
  • Epitopes, B-Lymphocyte
  • Epitopes, T-Lymphocyte
  • Immunoglobulin A
  • Immunoglobulin A, Secretory
  • Immunoglobulin G
  • Vaccines, Synthetic
  • Cholera Toxin
  • Urease