Brucella spp. are facultative intracellular pathogens which can stay alive and multiply in professional and nonprofessional phagocytes. Immunity against Brucella melitensis involves antigen-specific CD4(+) and CD8(+) T-cells activation and humoral immune responses. Due to negative aspects of live attenuated vaccines， much attention has been focused on finding Brucella-protective antigens to introduce them as potential subunit vaccine candidates.
Brucella spp. are facultative intracellular pathogens which can stay alive and multiply in professional and nonprofessional phagocytes. Immunity against Brucella melitensis involves antigen-specific CD4(+) and CD8(+) T-cells activation and humoral immune responses. Due to negative aspects of live attenuated vaccines， much attention has been focused on finding Brucella-protective antigens to introduce them as potential subunit vaccine candidates.
