An Indirect Fluorescent-Antibody Technique for Study of Uncomplicated Gonorrhea. I. Methodology

Abstract

An indirect fluorescent-antibody technique was developed for detection of antibodies to Neisseria gonorrhoeae in sera from patients with uncomplicated gonorrhea. The test antigen is a strain of N. gonorrhoeae selected for its stability in the laboratory and for its reactivity with sera from culturally positive females. AI: 16 dilution of sera obviated the reactivities associated with natural antibodies in normal sera. The specificities, strengths, and degree of fluorescence of the conjugate were defined to establish data for comparison with other polyvalent reagents and to minimize preferential recognition of anyone immunoglobulin class. Seventy-nine percent of sera from culturally positive females were reactive; only 4% of sera from culturally negative females reacted in the test. Reproducibility was 94% as judged by duplicate examination of 340 coded sera. The discrepant pairs (6%) were read as either 1+ or 2+ fluorescence. Only 15% of the 340 sera were in the borderline (1+, 2+) area where judgment of fluorescence is most critical.