LACK OF CYTOTOXIC ACTIVITY AGAINST MYCOBACTERIUM-LEPRAE 65-KD HEAT-SHOCK PROTEIN (HSP) IN MULTIBACILLARY LEPROSY PATIENTS

Cytotoxic T cells play an important role in host defence mechanisms, a s well as in the immunopathology of leprosy. In this study, we evaluat ed whether Mycobacterium leprae hsp18, hsp65 and Myco. tuberculosis hs p71 could induce cytotoxic T cell activity against autologous macropha ges pulsed with these hsp. Paucibacillary (PB) patients and normal con trols generated more effector cells than multibacillary (MB) patients with all three hsp tested. There was no crossreactivity between any of the hsp tested. Mycobacterium leprae hsp65 induced cytotoxic response s only in those MB patients undergoing an erythema nodosum leprosum (E NL) episode. Although hsp65 and hsp18 induced similar proliferation in MB patients, a high proportion of these patients did not generate cyt otoxic effector cells in response to hsp65. Hence, those T cells react ing to hsp65 may play an important role in the control of Myco. leprae infection.