Immunity in Experimental Syphilis IV. Serological Reactivity of Antigens Extracted from γ-IrradiatedTreponema pallidumandTreponema reiteri

Miller, James N. (University of California School of Medicine, Los Angeles),J. H. De Bruijn, and J. H. Bekker . Immunity in experimental syphilis. IV. Serological reactivity of antigens extracted from γ-irradiatedTreponema pallidum andTreponema reiteri . J. Bacteriol.91: 583–587. 1966.—Ultrasonic lysate preparations extracted from virulentTreponema pallidum , Nichols strain, suspensions exposed to 652,800 R of γ-irradiation exhibited a loss in the serological reactivity of their heat-labile antigens; the heat-stable components of both the lysate and residue antigens were unaffected. The activity of heat-stable, cardiolipinT. pallidum complement-fixing antigen obtained from similarly irradiated organisms was also unaltered. γ-Irradiation of the cultivableTreponema reiteri with dosages as high as 6,500,000 R failed to alter serologically either the heat-labile or heat-stable component of its lipopolysaccharide-protein (Reiter protein) antigen. The reactivity of the lipopolysaccharide portion of the Reiter protein complex with an antiserum toT. pallidum Nichols indicates previously unsuspected antigenic differences between the rabbit-adapted Nichols strain of the organism and so-called “wild” human strains ofT. pallidum in which this antigen is generally absent.