IMMUNOLOGICAL RECOGNITION IN NATURALLY FA SCIOLA-HEPATICA INFECTED SHEEP, MONITORED BY AN ENZYMATIC IMMUNOELECTROTRANSFERENCE ASSAY (WESTERN-BLOTTING)

In order to verify the presence of immunodiagnostic antigenic fraction s and their persistence in the course of a natural infection, the immu ne response of Fasciola hepatica infected sheep was studied. Serum sam ples from 10 lambs were obtained before their exposure to the natural infection and then every 15 days after exposure, for a period of 12 mo nths. Two antigenic preparations, namely somatic and excretion-secreti on F. hepatica antigens, were analized by polyacrylamide gel electrofo resis followed by an enzymatic immunoelectrotransference assay. The se rum samples were incubated individually as well as in pools. Additiona lly, 30 serum samples from sheep with other parasitic infections (hyda tid cysts, Thysanosoma actinioides) were also included as controls. Th e pattern of antigenic recognition presented four prominent band group s: 36-38; 30-33; 26-28 and 19-23 kDA, which were only detected in F. h epatica infected sheep. Theses were observed 1.5 month after infection up to the end of the experimental period, but were not detected in sh eep with other parasitic infections.