Antigenic analysis of Mycobacterium leprae.

About twenty distinct antigenic components have been demonstrated in Mycobacterium leprae (M. leprae) by crossed immunoelectrophoresis against a rabbit antiserum produced by immunization with concentrated M. leprae antigen. This system allows a more detailed analysis of the antigenic relationship between M. leprae and other mycobacteria and a better characterization of the antigenic content of various M leprae preparations than with previously available anstisera of the antigenic content of various M. leprae preparations than with previously available antisera which reacted with far fewer components. The antibody activity in sera of patients with lepromatous leprosy was studied by incorporating the sera into the intermediate gel of the M. leprae reference system. Antibodies were found against only seven of the components. Since those compared are all known to be cross-reacting widely with antigens of other mycobacteria, it is speculated that cross-immunization may influence the antibody response in lepromatous leprosy.