Identification of circulating antibodies in fasciolosis and localization of 66 kDa antigenic target using monoclonal antibodies

We identified three specific circulating antibodies in serum of cattle natu rally infected with Fasciola gigantica. Two of the antibodies were found to react specifically to 97 and 66 kDa antigenic molecules of adult worm tegu mental membrane extract. The third antibody was identified by the reaction with 26-28 kDa molecule of the excretory/secretory antigens. Monoclonal ant ibody against 66 kDa protein was developed and used for localization of its antigenic target in adult worm frozen sections. The experiment demonstrate d that 66 kDa protein is a component on the outer surface membrane and on t he membrane lining of the caecal epithelial of adult worm. The 66 kDa antig en was considered as a promising candidate for immunodiagnosis and vaccine.