Passive hemagglutination test for detection of antibody to gonococcal ribosomal antigen in sera from patients with asymptomatic gonorrhea.

Ribosomal fractions were obtained from a culture of type 2 Neisseria gonorrhoeae strain P-17 which was isolated from a patient with an acute gonococcal infection; these fractions were purified to eliminate the components of the outer membrane complex by affinity chromatography (Sepharose-anti-outer membrane complex antibody conjugates were used as the solid immunosorbent), and the resulting preparation was designated the purified ribosomal fraction, The purified ribosomal fraction was used to detect antibody activity in sera obtained from culture-positive asymptomatic carriers and healthy controls by a passive hemagglutination test. This passive hemagglutination test had a specificity of 100% for both sexes and sensitivities of 99.4 and 88.2% for female and male carriers, respectively, when an antibody titer of more than 1:3 was defined as abnormal. Absorption of the sera with nongonococcal organisms did not affect the antibody activity, and no significant difference in antigenicity among various N. gonorrhoeae strains was observed in ribosomal fractions. An enzyme-linked immunosorbent assay was also used to measure the relative amounts of specific antibodies to the purified ribosomal fraction, and this assay revealed that the anti-purified ribosomal fraction antibodies were immunoglobulin G.