[Change in cell-mediated immunity to Mycobacterium leprae and Mycobacterium marinum in Hansen's disease patients].

The cell mediated immunity (CMI) to protein purified derivates of Mycobacterium leprae, Mycobacterium tuberculosis, Mycobacterium avium and Mycobacterium marinum was studied. Leukocyte Migration Inhibition (LMI) and Delayed Hypersensitivity skin reactions to these antigens were examined in 44 hanseniasis patients (20 quiescent Virchowians, 13 reactional Virchowians and 11 tuberculoid patients) and 15 healthy subjects. An impairment in LMI and Delayed Hypersensitivity tests to M. leprae and M. marinum was observed in Virchowians patients both quiescent and reactional. The CMI response to all mycobacterial antigens was increased in tuberculoid patients and was observed a poor response to M. leprae and M. marinum in healthy controls. Our results show a high correlation between the CMI response to M. leprae and to M. marinum (r = + 0,8). This close relationship between both antigens may express cross-reactivity.