Abstract

Helicobacter pylori is the leading cause of peptic ulcer and gastric cancer. Considering the importance of Helicobacter pylori in human diseases, develop a vaccine against it is necessary. Therefore, this study aimed to investigate the clearance of H. pylori with Formulation rCagA and LPS in a mouse model. The formulations; rCagA, LPS, rCagA/LPS were evaluated against clearance of H. pylori. All of Mice groups were immunized three times orally then two times intramuscularly (IM). Mice were challenged with H. pylori strain SS1, Fourteen days after the last immunization. Spleens and gastric tissues were collected from mice. Antigen-specific interleukine responses were surveyed in the spleen of mice that immunized before and post-challenge by ELISA technique. The clearance of H. pylori was measured in spleen and gastric tissues. Data were analyzed using ANOVA followed by Dunnett's post hoc test. Differences between CFU in experimental groups were evaluated by Student's t-test. The cellular and humoral responses were compared by the non-parametric Mann-Whitney U test. Immunization of mice with formulationrCagA-LPS induced a strong Th1 immune response (P<.05). The rCagA - LPS - CpG group induced a more increase IL-4 than IFN-gamma (P<.05). Splenocytes produced high levels of IL-10 after challenge with rCagA-LPS. Mice that immunized with rCagA-LPS-CpG and LPS-CpG secreted significantly more IFN gamma titer than others (P<.05). The clearance test showed the reduction of 6 logs of H. pylori. Immunization with current combinations was safe in animal models and was able not only trigger appropriate responses but decrease H. pylori ss1 colonization, too.