Studies on Clonorchis sinensis. II. Development of an antigen for complement fixation and studies on the antibody response in infected rabbits

An antigen was prepared from adult C. sinensis by treating dehydrated worms with anhydrous ether at −18 °C before extracting with buffered saline solution. Preliminary ether extraction eliminated anticomplementary activity and reduced cross reactivity without effecting the capacity to react specifically with homologous antiserum. Employing the new antigen in studying the specific antibody response in experimentally infected rabbits, it was shown that it may be used with success to determine host antibody response.