Host Nonresponsiveness Does not Interfere With Vaccine-Mediated Protection Against Gastric Helicobacter Infection.

Background: Helicobacter pylori pathogenesis results from the inflammation induced by chronic infection. CBA mice are nonresponsive to gastric Helicobacter infection, providing a useful model for examining host regulation of Helicobacter-induced gastritis. We examined whether gastric Helicobacter nonresponsiveness impacts upon vaccine efficacy and whether immune-mediated protection could occur in the absence of inflammation.
Methods: Mice were vaccinated prior to challenge with Helicobacter felis or H. pylori. Gastritis and H. felis colonization was evaluated histologically. H. pylori colonization was quantified by colony-forming assay.
Results: Immunizations protected CBA mice against challenge with either H. felis or H. pylori. Protection against H. felis was marked by a loss of nonresponsiveness and development of an atrophic gastritis with mucus metaplasia. However, vaccine-induced protection against H. pylori was only associated with cell infiltration into the gastric mucosa.
Conclusions: Nonresponsiveness to gastric Helicobacter infection did not interfere with vaccination-induced protection. Vaccine-induced protective immunity against H. pylori was linked with the induction of cellular infiltration, but importantly not atrophic gastritis.
(© 2015 John Wiley & Sons Ltd.)