Studies on immune response to Mycobacterium lepraemurium. Evaluation of the cell-mediated immune response in mice.

Evaluation of the cell-mediated immune response (CMI) in mice infected with Mycobacterium lepraemurium revealed a disturbance in the nonspecific components of the CMI. Expression of delayed type hypersensitivity (DTH) in skin test studies indicated that the organism is capable of inducing skin reactivity in mice. This begins at a very early stage of infection and subsequently decays as the infection becomes disseminated. At this stage, gross pathological changes are noticed followed by a high rate of mortality. An in vitro correlate of DTH, namely lymphocyte transformation, was in concordance with the observation on DTH. The suppression of CMI appears to be due to extensive multiplication of the infecting pathogen within the host system.