DIAGNOSTIC UTILITY OF FRACTIONATED URINARY FILARIAL ANTIGEN

Urinary filarial antigen isolated from urine samples of microfilaraemi c patients was analysed for its antigenic activity by immunoblotting a nd enzyme linked immunosorbent assay.techniques. SDS-PAGE fractionatio n of urinary filarial antigen showed 11 protein bands, of which two sh owed reactivity with immunoglobulin-G fraction of filarial serum immun oglobulin in immunoblotting. Antigenic analysis of SDS-PAGE fractions of urinary filarial antigen by inhibition enzyme linked immunosorbent assay using filarial serum immunoglobulin-G and Wuchereria bancrofti m icrofilarial excretory-secretory antigen revealed 3 fractions, numbers 5, 6 and 9 with significant activity. In indirect enzyme linked immun osorbent assay using fractions 5 and 6, filarial immunoglobulin-G anti body was detected in about 90% of microfilaraemics, 80% clinical filar iasis and 20% of endemic normal individuals. Further, there was no pho sphorylcholine epitope in these fractions. Fractions 5 and 6 can be a candidate antigens for the immunodiagnosis of filariasis.