Abstract

The development of vaccines against Brucella is necessary. The formulations rCagA/OMP/LPS were evaluated against the clearance of Brucella. All of the mouse groups were immunized three times orally and followed two times by IM. Two weeks after the last immunization mice were challenged with B. abortus strain 544. Blood and spleen samples were collected from mice. Antigen-specific interleukine responses were measured in the spleen of immunized mice before and post-challenge by ELISA. Specific IgG1,2 isotopes were measured from sera before and after challenge. Sandwich ELISA assays were used to determine IFN-gamma, IL-4 and IL-10 levels in the supernatants of the splenocyte cells. Statistical analysis of IFN-gamma titers indicated a significant difference between all groups with Mock (p = 0.00). However, there was no significant difference between other groups. Furthermore, the analysis of IL-10 titers had similar results. The statistical analysis for IL-4 showed a significant difference between rCagA with LPS-rCagA conjugate and LPS-rCagA+ CpG groups (p = 0.001). Statistical analysis between IFN-gamma and IL-4 titers showed a significant difference among all groups (p = 0.00). Statistical analysis between IFN and IL-10 titers showed a significant difference among all groups (p = 0.00). Statistical analysis between IL-10 and IL-4 titers showed no significant difference in any group. Clearance finally was 7 log with OMP/rCagA against B. abortus strain 544. Immunization with the current combination was safe in animal models and was able to induce appropriate responses and also decrease Brucella colonization.