The immune response of goats vaccinated with low and high doses of Brucella melitensis Rev 1.

The serological response, lymphocyte reactivity, and dermal hypersensitivity reactions of goats vaccinated with high and low doses of Brucella melitensis Rev 1 organisms to Brucella antigens were studied. Antibodies to soluble antigen A2 were detectable by immunoelectrophoresis (IE), appeared later than agglutinating antibodies but disappeared faster in most vaccinated animals. Anti-A2 antibodies appeared earlier in goats which received the high dose. Antibodies to polysaccharide B antigen were not detected. Lymphocytes reactive to Brucella antigens in lymphocyte transformation assays appeared at variable times after vaccination. In contrast to the humoral response to antigen A2, the appearance of circulating, reactive lymphocytes was not dependent on vaccine doses. All vaccinated animals demonstrated dermal hypersensitivity reactions to one of the antigenic extracts. Skin reactions peaked at 24 hrs post inoculation. The reactions were elicited when all but one goat had undetectable anti-A2 antibodies and no circulating, reactive lymphocytes as measured in whole blood lymphocyte transformation assays.