Coproantigens in gut tapeworm infections: Hymenolepis diminuta in rats

A capture enzyme-linked immunosorbent assay (ELISA) for the detection of Hymenolepis diminuta coproantigen in detergent-solubilised faecal supernatants was developed. The assay was sensitive to 400 ng H. diminuta protein/ml faecal supernatant and to 30 ng/ml in PBS 0.3% Tween. Faecal antigen levels started to rise on day 7 post infection and peaked on day 20. Following drug treatment of infected rats with 10 mg/kg praziquantel, there was an initial steep rise in faecal antigen levels, followed by a decline to background levels for uninfected animals by day 7 post treatment. When assayed against faecal supernatants prepared from H. microstoma, H. citelli, Diphyllobothrium ditrenum, Necator americanus, Strongyloides ratti and Nematospiroides dubius infections as well as uninfected animals, all results from these groups were 2 SD below those for animals infected with H. diminuta. The application of such a test to important intestinal cestodiases in man is discussed.