Abstract
Electrofocusing of F. hepatica adult antigen in granulated gels separated the material into 22 arbitrary fractions. Polyacrylamide gel analysis demonstrated groups of proteins with similar isoelectric points in 19 of the fractions. A microplate ELISA [enzyme linked immunosorbent assay] detected antigens in all 22 fractions and was used to test the serum antibody response in infected rats, rabbits, lambs and calves to these antigen fractions. Apparently, rat and calf sera gave a much stronger response than rabbit and lamb sera to the antigen which separated above pH 7.0. The greater efficiency of the rat and bovine immune systems in combating reinfection with F. hepatica may be related to this response.