Methods for the Detection of a Specific Mycobacterium leprae Antigen in the Urine of Leprosy Patients

Two methods for detecting the phenolic glycolipid, PGL‐1, a Mycobacterium leprae‐specific molecule, in the urine of leprosy patients are described. Both methods rely on the 100‐fold preconcentration of the urine, which can be accomplished by a single‐step ultrafiltration procedure. The equivalent of approximately 2.5/μ of PGL‐1/ml was detected in the urine of LL patients with an inhibition ELISA. The second method, a direct dot‐blot assay on nitrocellulose paper, was much simpler and more sensitive. As little as 3 ng of antigen was detected by the dot‐bolt technique. PGL‐1 was detected in the urine of LL patients.