title: Use of fractionated urinary filarial antigen in the diagnosis of human filariasis.
abstract: Fractionated urinary filarial antigen UFA C2 has shown high antigenic activity after absorption of urinary albumin present in the fraction. As little as 500 ag (10(-18) g) of albumin absorbed UFA C2, labelled as UFA C2-A, was found to be sufficient to detect filarial antibody. Stick enzyme immunoassay to assess the immunodiagnostic potential of UFA C2-A indicated filarial IgG antibody in 89% of microfilaraemic (mf) cases, 84% of clinical filariasis and 7% of endemic normals. UFA C2-A was found to be present in circulation in active as well as clinical infections as observed by inhibition assay using UFA C2-A penicillinase conjugate. Eighty-six per cent of mf, 50% of clinical cases and 6% of endemic normal subjects revealed parasite antigen to UFA C2-A on further serological analysis. None of the non-endemic normal sera showed the presence of filarial antibody/antigen to UFA C2-A. Furthermore, the test to determine phosphorylcholine (PC) bearing epitopes in UFA C2-A indicated no immunological reaction with anti-PC monoclonal antibody by avidin-biotin enzyme linked immunosorbent assay (ELISA). The highly sensitive and more easily obtainable non-PC urinary filarial antigen, UFA C2-A, is of great immunodiagnostic interest for lymphatic filariasis.
authors.affiliation: Department of Biochemistry, Mahatma Gandhi Institute of Medical Sciences, Sevagram, India.
authors.forename: P
authors.initials: P
authors.lastname: Ramaprasad
authors.forename: B C
authors.initials: BC
authors.lastname: Harinath
mesh_terms: D000818:Animals; D000947:Antigens, Helminth / Q000652:urine*; D005591:Chemical Fractionation; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D018604:Epitope Mapping; D005368:Filariasis / Q000175:diagnosis* / Q000276:immunology / Q000652:urine; D006801:Humans; D012680:Sensitivity and Specificity; D014958:Wuchereria bancrofti / Q000276:immunology*
chemical_list: D000947:Antigens, Helminth