Abstract: We report the results of detecting anti-PGL-I antigen and antibody in sera from lepromatous leprosy patients before and after MDT with M-DotELISA and ELISA. The results indicated that the speed of antigen reducing in the sera of patients was much faster that that of antibody reducing after chemotherpy, the difference is very significant(U=9.05, >2.58, P<0.01). The decreasing of PGL-I antigen was fastest (79.14%)at the first month and was 99% decreasing at the third months. It suggests that the detection of PGL-I antigen might be used for monitoring the early therapeutic effect in mutibacillary leprosy, finding out of drug-resistant M. leprae strains, and screening of new drugs for the treatment of leprosy.

Key words: Leprosy, Drug therapy, Antigen, detection