Abstract: Objective To reveal the variation of specific IgM type antibodies in the mice infected by M.leprae. Methods The serum level of IgM antibody against M.leprae from 50 normal mice and 127 mice infected with M.leprae were detected with ND-O-BSA-ELISA. Results The serum level of IgM antibody-against M.leprae in infected mice was significantly higher than that in normal mice(P<0.01). There were significant differences between untreated group of mice and treated group of mice (P<0.01) between different drug. Treated groups (P<0.01), and between different dosage groups in the same drug. Treated mice (P<0.01 or P<0.05). Conclusion The serum level of IgM antibody against M.leprae in infected mice is consistent with bacterial load and related to the severity of infection and the therapeutical effects.

Key words: ND-O-BSA-ELISA, Mycobacterium, Leprae, Serology