Systemic immunization with unadjuvanted whole Helicobacter pylori protects mice against heterologous challenge

Abstract

Background: Adjuvant-free vaccines have many benefits, including decreased cost and toxicity. We examined the protective effect of systemic vaccination with adjuvant-free formalin-fixed Helicobacter pylori or bacterial lysate and the ability of this vaccine to induce protection against heterologous challenge. Materials and Methods: Mice were vaccinated subcutaneously with H. pylori 11637 lysate or formalin-fixed bacteria, with or without ISCOMATRIXTM adjuvant, then orally challenged with H. pylori SS1. Serum was taken prior to challenge to examine specific antibody levels induced by the vaccinations, and protection was assessed by colony-forming assay. Results: Vaccination with H. pylori 116..