BACKGROUND & AIMS: Oral immunization with recombinant Helicobacter pylori urease (rUre) coadministered with a mucosal adjuvant protects mice against challenge with Helicobacter felis. In this study, the duration of protection and gastritis after challenge were characterized at sequential time intervals up to 1 year. METHODS: Outbred Swiss-Webster mice were orally immunized with rUre plus adjuvant and examined for the presence of H. felis infection and leukocyte infiltration into the gastric mucosa. RESULTS: When defined by gastric urease activity, 70%-95% of rUre-immunized mice were protected for between 2 and 57 weeks. Challenge with H. felis increased the inflammatory response in the gastric mucosa of rUre-immunized mice, which also had elevated CD4+ and CD8+ T cells. The CD8+ cells represented a population of gastric intraepithelial cells, which expressed the mucosal alpha E-integrin. Epithelial changes consisting of parietal cell loss and hyperplasia of the epithelium occurred in approximately 20% of the mice. Antimicrobial triple therapy significantly decreased the degree of gastritis and epithelial alteration in the stomach. CONCLUSIONS: These results indicate that oral immunization of mice with rUre produces a long-lasting inhibition of H. felis infection but that residual bacteria may produce a persistent lymphocytic infiltration under these experimental conditions.
BACKGROUND & AIMS: Oral immunization with recombinant Helicobacter pylori urease (rUre) coadministered with a mucosal adjuvant protects mice against challenge with Helicobacter felis. In this study, the duration of protection and gastritis after challenge were characterized at sequential time intervals up to 1 year. METHODS: Outbred Swiss-Webster mice were orally immunized with rUre plus adjuvant and examined for the presence of H. felisinfection and leukocyte infiltration into the gastric mucosa. RESULTS: When defined by gastric urease activity, 70%-95% of rUre-immunized mice were protected for between 2 and 57 weeks. Challenge with H. felis increased the inflammatory response in the gastric mucosa of rUre-immunized mice, which also had elevated CD4+ and CD8+ T cells. The CD8+ cells represented a population of gastric intraepithelial cells, which expressed the mucosal alpha E-integrin. Epithelial changes consisting of parietal cell loss and hyperplasia of the epithelium occurred in approximately 20% of the mice. Antimicrobial triple therapy significantly decreased the degree of gastritis and epithelial alteration in the stomach. CONCLUSIONS: These results indicate that oral immunization of mice with rUre produces a long-lasting inhibition of H. felisinfection but that residual bacteria may produce a persistent lymphocytic infiltration under these experimental conditions.
Authors: H Kleanthous; G A Myers; K M Georgakopoulos; T J Tibbitts; J W Ingrassia; H L Gray; R Ding; Z Z Zhang; W Lei; R Nichols; C K Lee; T H Ermak; T P Monath Journal: Infect Immun Date: 1998-06 Impact factor: 3.441
Authors: Kathryn A Eaton; Joanne V Gilbert; Elizabeth A Joyce; Amy E Wanken; Tracy Thevenot; Patrick Baker; Andrew Plaut; Andrew Wright Journal: Infect Immun Date: 2002-02 Impact factor: 3.441