COMPARISON OF 22 SPECIES OF MYCOBACTERIA BY IMMUNODIFFUSION AGAINST AN ABSORBED REFERENCE LEPROSY SERUM

Abstract

Lithium acetate antigenic extracts of 22 species of acetone-treated mycobacteria were tested by immunodiffusion precipitation for reactivity with a pool of sera from treated lepromatous leprosy patients (ARLS). This ARLS was adsorbed with Mycobacterium bovis (BCG), M. vaccae, cardiolipin and lecithin to make it specific for M. leprae when used in an indirect immunofluorescence test. The ARLS produced 2 precipitin lines with M. leprae extract, 1 of which formed a line of identity with extracts of M. lepraemurium and M. bovis (BCG). Recognition without reactions of identity was produced between ARLS and M. flavescens, M. gastri, M. gordonae and M. nonchromogenicum. The ARLS did not recognize the 15 other species including the human pathogens, M. tuberculosis, M. intracellulare, M. kansasii, M. scrofulaceum and M. marinum. Thus, serologic tests for M. leprae infection may be affected by antibodies to antigens shared by M. leprae and other mycobacteria. The significance of these shared antigens will depend upon the prevalence of human immune responses to myocobacteria containing the shared antigens in any given community.