DEVELOPMENT OF A RAPID IMMUNOASSAY FOR SYPHILIS

SYPHILIS, STILL A MAJOR SERIOUS INFECTIOUS DISEASE, CAN BE TREATED EFFECTIVELY IF DIAGNOSED EARLY. THE NUMBER OF DEATHS FROM SYPHILIS IN THE UNITED STATES HAS SHOWN A STEADY DECREASE, BUT THE NUMBER OF SYPHILIS CASES HAS NOT SHOWN A SIGNIFICANT DROP. SEROLOGICAL TESTS PLAY A MAJOR ROLE IN THE DIAGNOSIS OF SYPHILIS. THESE TESTS MUST BE PERFORMED BY QUALIFIED TECHNICIANS IN A LABORATORY. THE PROPOSED PROJECT IS TO DEVELOP A RAPID, SIMPLE, RELIABLE, AND INEXPENSIVE IMMUNOASSAY SUITABLE FOR USE IN PHYSICIANS' OFFICES. ANTIGENS OF THE CAUSATIVE AGENT TREPONEMA PALLIDUM WILL BE COATED ONTO A FILTER PAPER AS A SMALL DOT. IN THE ASSAY, THE TEST SERUM SAMPLE, ENZYME-LABELED ANTIBODIES TO HUMAN IMMUNOGLOBULINS, AND SUBSTRATE ARE ADDED SEQUENTIALLY TO THE ANTIGEN DOT. NO INCUBATION IS REQUIRED, SINCE THE SAMPLE AND REAGENTS DIFFUSE RAPIDLY, CONTACTING AND REACTING INSTANTANEOUSLY WITH EACH OTHER IN THE FIBER MESH. THE RESULTS ARE READ VISUALLY, AND A BLUE DOT INDICATES A POSITIVE REACTION. THE RESEARCH WILL FOCUS ON: (1) SELECTION OF FILTER PAPERS THAT WILL GIVE A MAXIMUM COATING OF ANTIGENS BUT A MINIMUM NONSPECIFIC ADSORPTION OF SERUM AND REAGENTS; (2) BEST CONDITIONS (TEMPERATURE, TIME, BUFFER, AND CONCENTRATION) FOR COATING ANTIGENS; (3) POSTCOATING (MATERIALS AND CONDITIONS) TO MINIMIZE OR ELIMINATE BACKGROUND REACTIONS; AND (4) VOLUME AND CONCENTRATION OF SAMPLE AND REAGENTS. A REFINED ASSAY PROCEDURE WILL BE TESTED WITH A PANEL OF MORE THAN 200 CLINICAL SERUM SAMPLES.