Experimental mycobacterial infections of CBA/N mice

In an effort to assess the contribution of B-lymphocyte-mediated mechanisms to the immune responses to several mycobacteria, responses to these intracellular pathogens were compared in immunologically normal CBA/CaHN mice and in histocompatible CBA/N (Xid) mice, which exhibit abnormalities of B-lymphocyte function. Swelling in response to local inoculation with Mycobacterium marinum was significantly greater in the hind feet of CBA/CaHN mice than in those of CBA/N mice, but the difference was very small. Survival of mice of both strains after i.v. challenge with M. marinum or i.p. challenge with M. leprae-murium did not differ significantly. Finally, multiplication of M. leprae in the footpads of mice of both strains did not differ significantly. Thus, B-lymphocyte-mediated mechanisms do not appear to be important in the immune responses of mice in experimental infections with these mycobacterial species.