ANTIGENIC RELATIONSHIPS BETWEEN MYCOBACTERIA AS DETERMINED BY AGAR DIFFUSION PRECIPITIN TECHNIQUES

Abstract

Antigenic relationships between 42 strains of mycobacteria were investigated by means of the Oudin and a modified Ouchterlony method by the use of culture filtrates as antigens. The 42 mycobacterial strains were divisible into 4 antigenic groups designated as I, II, III, and IV. Group I was the largest group and contained mycobacteria whose culture filtrates contained 4 distinct antigens capable of precipitating antibody in homologous sera. Member strains of Group I consisted of known human strains (both virulent and avirulent), all but one of a group of atypical acid-fast organisms isolated from human patients, one attenuated bovine strain, and one strain of Mycobacterium avium. Group II consisted mainly of mycobacterial strains of bovine origin and one avian strain. Only 2 antigens were produced by this group, both of which were identical to two of those which appeared in Group I. Group III consisted mainly of saprophytic mycobacterial strains. The organisms produced 4 antigens which were entirely different from antigens of Groups I, II, and IV. Group IV consisted of a single strain of an atypical acid-fast organism which produced 2 antigens unrelated to those produced by the organisms of the other groups.