Bacillary growth, interleukin 2 production defect, and specific antibody secretion governed by different genetical factors in mice infected subcutaneously with Mycobacterium lepraemurium.

Different mouse strains were infected subcutaneously in the footpad with 10(7) Mycobacterium lepraemurium (MLM). At various stages of the infection, the number of acid-fast bacilli (AFB) in different organs, spleen cell interleukin 2 production, and specific IgM and IgG serum antibodies to MLM sonicate were assessed. Strains were separable into two distinct groups depending on the number of AFB recovered from the different organs, without any obvious influence of the Bcg gene. Thus C57BL/6, DBA/2, (C57BL/6 X DBA/2)F1 and C3H/Pas mice belonged to the high resistance group and DBA/1, BALB/c, and CBA strains to the low resistance group. Interleukin 2 production was depressed only in C57BL/6 and C3H/Pas mice. Anti-MLM antibody response also markedly varied according to strains, in terms of antibody titers, Ig class distribution, and species specificity, but with a different genetic pattern from that observed for MLM growth control.