Use of immunologic techniques to detect chemotherapeutic success in infections with Fasciola hepatica. II. The enzyme linked immunosorbent assay in infected rats and rabbits.

An enzyme-linked immunosorbent assay (ELISA) was developed using microtiter plates for the immunodiagnosis of fascioliasis in rats and rabbits using extracts of adult worms partially purified by gel filtration chromatography using Sephacryl S-200. Partial purification was necessary to eliminate cross-reactivity with antisera having antibodies to schistosomes. Soft polyvinyl plates clearly gave superior results over hard polystyrine plates. Titers rose by 4 weeks of infection in rats with fascioliasis, by 6 weeks in the case of rabbits, and remained high through at least 12 and 28 weeks, respectively. Titers drop rapidly when animals are successfully treated with a fasciolicidal drug at 4--6 weeks of infection. The results show that the ELISA can be employed for the serodiagnosis of fascioliasis in rats and rabbits and is useful for the prediction of chemotherapeutic success.