INDUCTION OF ANTIBODY AND PROTECTIVE RESPONSES IN MICE BY BRUCELLA O-POLYSACCHARIDE BSA CONJUGATE

A Brucella conjugate vaccine was synthesized by covalently coupling the O-polysaccharide (PS) obtained from Brucella melitensis 16M, to bovine serum albumin (BSA). The conjugate (PS-BSA) was non-toxic for mice. When injected at two doses (10 or 1-mu-g) in mice, it induced the production of antibodies and the boost was shown to be efficient if administered after 10 weeks. Immunization of mice with 10-mu-g of conjugate conferred significant protection against virulent challenge with B. melitensis H38, similar to that obtained with the reference vaccine H38.