A 28KDa recombinant outer membrane protein of Brucella melitensis downregulates type-1 immune response in mice

Abstract

A 28 kDa recombinant outer membrane protein (r-omp28) of Brucella melitensis was evaluated for the induction of immune response in mice. The study demonstrated the downregulation of type-1 immune response in mice vaccinated with r-omp28 of B. melitensis. The level of IgG2a was observed significantly lower than IgG1 in mice immunized with r-omp28. The cytokine profile and proliferation of cells was characteristic of Th2 type as we detected significantly high level of IL-10 but no or significantly low level of IL-2 and IFN-γ. Further, the production of gamma-interferon (IFN-γ) was downregulated by r-omp28. Therefore, it implies that B. melitensis r-omp28 might down-regulates type-1 immune response in vaccinated mice.