An enzyme-linked immunosorbent assay for detecting anti-Echinostoma trivolvis (trematoda) IgG in experimentally infected ICR mice. Cross-reactivity with E. caproni.

An enzyme-linked immunosorbent assay (ELISA) utilizing surface glycocalyx-membrane crude antigen of adult Echinostoma trivolvis was developed for the detection of circulating anti-E. trivolvis IgG in experimentally infected ICR mice. An antigen concentration of 10.0 micrograms/ml was used, and it was possible to detect anti-E. trivolvis IgG at a dilution of 1/3,200. On day 10 postinfection (p.i.), all infected mice had anti-E. trivolvis IgG reactive with the surface glycocalyx antigen. The IgG level varied over a 40-day period, showing a time-dependent pattern with a peak on day 16 p.i. The results concerning reciprocal cross-reactivity indicate that adult E. trivolvis and E. caproni share at least some of the surface antigens and express species-specific antigenic determinants in ICR mice at similar, nonsignificantly (P = 0.76) different levels.