Partial characterization of antigens from M. leprae evoking IgG and IgM antibodies in armadillos

Armadillo IgG and IgM antibody responses to Mycobacterium leprae were analyzed using isotypic-specific antisera by means of immunoblotting. Blots developed for IgG antibodies to M. leprae showed multiple protein antigens (Mr = 12-90 K) in some heavily infected armadillos. In contrast, blots developed for IgM antibodies to M. leprae showed a single, broad, diffuse band of immunoreactivity at approximately 33 kDa. The 33-kDa immunogen was detectable with silver stain modified for carbohydrate reactivity, suggesting the presence of a polysaccharide component. In addition, binding of 125I-concanavalin A to the 33-kDa component demonstrated the presence of mannose and/or glucose residues.