Negative observations on immunological side effects of rifampin and dapsone in mice.

The in vivo effects of rifampin and dapsone on immunological responses were investigated using mice immunized with sheep erythrocytes. The number of cells producing antibody was not affected by a clinical (1 CD) or a threefold excess dose (3 CD) of the drugs administered for ten days. A similar result was obtained in an experiment using a mouse strain known to be low responders to the antigen. Induction of suppressor cells acting on antibody production was not influenced by 3 CD or 6 CD of the drugs. Neither delayed-type hypersensitivity nor induction of the suppressor cell population acting on delayed hypersensitivity was affected by 3 CD of the drugs. Phagocytosis of sheep erythrocytes by peritoneal cells and the growth of a tumor were not altered by 6 CD of the drugs.