Demonstration of circulating anti-LAM and anti-PGL anti-bodies, 35kDa Mycobaterium leprae antigen and gene encoding for 36kDa protein in plasma from leprosy patients

Plasma samples from blood of active leprosy patients belonging to different clinical forms and healthy volunteers were subjected to demonstrate antibody response, using indirect enzyme linked immunosorbent assays (ELlSAs), against lipoarabinomannan (LAM) and phenolic glycolipid-1 (PGL). Same samples were also used for detection of 35kDa M. leprae antigen by sandwich ELISA and gene segment of M. leprae encoding 36kDa protein by polymerase chain reaction (PCR). Overall positivity rates with LAM and PGL based ELiSAs were observed to be 60.0% and 33.3% respectively. On the other hand the pC)sitivity rates for 35kOa antigen and PCR assay were found to be 13.3% and 33.3% respectively. All the above described assays were found to be highly specific with reference to samples from healthy individuals. Thus, the results indicated that the LAM based ELISA (LAM-E) is more sensitive than PGL based ELISA (PGL-E), 35kDa detecting ELISA (AG-E) and PCR based assay.