Antigens of mycobacterial cell walls.

Three antigenic fractions from the cell walls of eight strains of mycobacteria were studied. Isolation and purification of these antigens were effected by enzymatic digestions, differential and sucrose gradient centrifugations, dialyses, and column chromatography. Two of the fractions were termed cell wall tuberculins (CWT-1, solubilized with lipase; CWT-2, solubilized with lysozyme); the third was termed "C" (cross-reacting) antigen. All appeared to be lipopolysaccharides. The CWT antigens, as compared with purified protein derivatives (human), were relatively species (group)-specific in both double immunodiffusion and guinea pig skin tests; in the latter, the reactions resembled those of delayed hypersensitivity. The C antigens reacted heterologously in double immunodiffusion and skin tests; the latter were the "immediate" type of reaction.