Development of a radioimmunoassay for the immunodiagnosis of schistosomiasis mansoni
Hillyer, G.V.; Soler de Galanes, M.
Boletin de la Asociacion Medica de Puerto Rico 78(10): 431-433
1986
ISSN/ISBN: 0004-4849 PMID: 3098258 Document Number: 700034
A solid phase radioimmunoassay using polyvinyl microtiter plates was developed for detecting antibodies to Schistosoma mansoni circumoval precipitin antigens. As little as 400 ng of the subpopulation of S. mansoni egg antigens involved in the circumoval precipitin reaction were coated onto polyvinyl microtiter plates. Serum samples at varying dilutions were applied, followed by a 125I-radiolabeled anti-mouse or anti-human IgG conjugate. A 1:200 serum dilution showed the greatest difference between the serum from controls and those infected with S. mansoni. Excellent discrimination was obtained between normal and infected mouse sera, as well as normal human (n=6) vs. sera from patients either confirmed parasitologically as infected with S. mansoni (n=8) or with antibodies as determined by a positive circumoval precipitin reaction (n=7). In mice infected with S. mansoni antibody levels rose by the 8th week of infection. Six sera from non-infected individuals (tested parasitologically) and 8 of 10 from individuals with confirmed fascioliasis were found negative in this test. Because of its high throughput capability, this radioimmunoassay would be a useful screening tool to detect antibodies to S. mansoni in populations where schistosomiasis endemicity is decreasing and/or where schistosomiasis is present at low intensities.