Protein/Protein, DNA/DNA and DNA/Protein based vaccination strategies using truncated Omp2b against Brucella infection in BALB/c Mice

The purpose of the present study was to evaluate the immunogenicity and protective efficacy of the truncated form of outer membrane protein 2b (TOmp2b) from Brucella abortus in BALB/c mice. Three immunization regimens Protein/Protein, DNA/DNA and DNA/Protein were used. Immunization of mice with all vaccine strategies elicited a strong specific IgG responses (IgG2a titers over IgG1) and provided T helper1 (Th1) oriented immune responses. Furthermore, Protein/Protein (Pro/Pro-) and DNA/Pro- vaccinated groups conferred protection levels against B. abortus challenge not significantly different from those induced by B. abortus RB51 vaccine stain. In conclusion, TOmp2b is potential to stimulate specific immune responses and to confer cross protection against B. melitensis and B. abortus infection. Therefore, TOmp2b could be introduced as a new subunit vaccine candidate against Brucella infection.