Antibodies to mycobacteria in human tuberculosis. II. Response to nine defined mycobacterial antigens with evidence for an antibody common to tuberculosis and lepromatous leprosy.

Antibodies to mycobacterial antigens were found in the sera of 33 of 52 patients with active tuberculosis by microimmunodiffusion tests. The highest titered sera were examined by a technique in which sera are placed in an intermediate gel between a reference goat antiserum field and a gel containing the antigens separated by one-dimensional electrophoresis. Special patterns caused by the presence of patient's serum during the two-dimensional electrophoresis showed that nine distinct antibodies could be designated by anodal migration of the corresponding nine antigens and the band position with respect to the reference pattern. Six of these antibodies were detected only by sera from selected patients, while the other three antibodies, "Lep," "Da," and "USJ 6," were also detected by the goat antiserum. Lep is present in patients with lepromatous leprosy but had never been described in those with tuberculosis. Monospecific human antisera were used to detect Lep and Da, and new antibody, during fractionation of mycobacterial culture filtrate.