In situ enzyme-linked immunosorbent assay to quantitate in vitro development of Eimeria tenella

An in situ enzyme-linked immunosorbent assay was developed to measure in vitro development of Eimeria tenella. The assay used a polyclonal, anti-merozoite serum produced by immunization with culture-derived, chromatographically purified merozoites. Although this antiserum cross-reacted with sporozoite-infected cultures (by indirect immunofluorescence and in situ enzyme-linked immunosorbent assay), it clearly distinguished the increase in antigen synthesized throughout intracellular growth. The assay can be used for high-throughput, anticoccidial drug screening, for which it gives quantitative results that are comparable to the published radiometric [( 3H]uracil incorporation) endpoint.