Oral vaccination of mice against Helicobacter pylori with recombinant Lactococcus lactis expressing urease subunit B

FEMS Immunol Med Microbiol. 2009 Aug;56(3):197-203. doi: 10.1111/j.1574-695X.2009.00566.x. Epub 2009 May 15.


To determine whether a protective immune response could be elicited by oral delivery of a recombinant live bacterial vaccine, Helicobacter pylori urease subunit B (UreB) was expressed for extracellular expression in food-grade bacterium Lactococcus lactis. The UreB-producing strains were then administered orally to mice, and the immune response to UreB was examined. Orally vaccinated mice produced a significant UreB-specific serum immunoglobulin G (IgG) response. Specific anti-UreB IgA responses could be detected in the feces of mice immunized with the secreting lactococcal strain. Mice vaccinated orally were significantly protected against gastric Helicobacter infection following a challenge with H. pylori strain SS1. In conclusion, mucosal vaccination with L. lactis expressing UreB produced serum IgG and UreB-specific fecal IgA, and prevented gastric infection with H. pylori.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Administration, Oral
  • Animals
  • Antibodies, Bacterial / blood
  • Bacterial Proteins / genetics
  • Bacterial Proteins / immunology*
  • Bacterial Vaccines / administration & dosage
  • Bacterial Vaccines / genetics
  • Bacterial Vaccines / immunology*
  • Colony Count, Microbial
  • Feces / chemistry
  • Gene Expression
  • Genetic Vectors*
  • Helicobacter Infections / prevention & control*
  • Helicobacter pylori / genetics
  • Helicobacter pylori / immunology*
  • Immunoglobulin A / analysis
  • Immunoglobulin G / blood
  • Lactococcus lactis / genetics*
  • Mice
  • Mice, Inbred BALB C
  • Protein Subunits / genetics
  • Protein Subunits / immunology
  • Recombinant Proteins / genetics
  • Recombinant Proteins / immunology
  • Stomach / microbiology
  • Urease / genetics
  • Urease / immunology*


  • Antibodies, Bacterial
  • Bacterial Proteins
  • Bacterial Vaccines
  • Immunoglobulin A
  • Immunoglobulin G
  • Protein Subunits
  • Recombinant Proteins
  • Urease