Detection and characterization of serum antitrichomonal antibodies in urogenital trichomoniasis.

Antibodies against Trichomonas vaginalis were detected in serum samples from 98 patients by three immunological assays. A good correlation was observed between the enzyme-linked immunosorbent assay and the immunofluorescence method, whereas it was found that the enzyme-linked immunosorbent assay correlated better with the current or past detection of organisms than did other serological methods (immunofluorescence and hemagglutination). Similar results were obtained with whole trichomonads and two T. vaginalis soluble antigenic preparations, which suggests that immunodominant moieties shared by several T. vaginalis strains were detected. The level of antibodies of the immunoglobulin A class was higher in patients with past records of trichomoniasis, but less significantly so than the total antitrichomonal antibody level. Antibodies of the four immunoglobulin G subclasses were detected. Immunoglobulin G1 antibody values were higher in female than male patients.