RÉSUMÉ
The response to recombinant 10-KD heat shock protein (HSP of Mycobacterium leprae (rML10) was evaluated by indirect ELISA in sera from leprosy patients, household contacts, tuberculosis patients and healthy controls a leprosy-endemic area in tne North East of Argentina. Some technical parameters were a analyzed: within-assay and between-assay variability, dose-response curves and dectability indexed (specificity and sensitivity) of ELISA applied to measure anti-10kDa antibodies. High levels of these antibodies have already been reported in positive baciloscopy patients; herein we have also demonstrated that tuberculosis patients sera cross-react with this M. leprae antigen. This test seems to have a low sensificity for leporsy detection; it confirms that antibodies against highly conserved HSP antigens are important in the polycional response against mycobacterial epitopes in leprosy as well as in tuberculosis.