In vitro studies of cell-mediated immunity in rabbits sensitized with Mycobacterium kansasii and Mycobacterium tuberculosis.

Rabbits, sensitized with M. kansasii, responded by a profound inhibition of migration of macrophages elicited by both antigens: the migration index for homologous antigen was 0.51 in the direct test and 0.65 in the indirect test; for heterologous antigen the indexes were 0.53 and 0.67. However, significant differences in reactivity were found in rabbits sensitized with M. tuberculosis. In the homologous system, high reactivity was maintained and the migration index reached the value of 0.53 in the direct and 0.63 in the indirect test. On the other hand, the heterologous antigen M. kansasii influenced the migration in both direct and indirect assays significantly less, the migration indexes being 0.62 and 0.72. The differences were statistically significant at 1% and 5% levels.