Antibody response of goldfish to a protein immunogen and to haptenic determinants.

The serum antibody response of goldfish (Carassius auratus) to protein immunogen (bovine serum albumin, BSA) and haptenic determinants was studied. The goldfish antibody response was compared with rabbit antibody response to similar antigens. The goldfish received BSA only or BSA with one of three haptens coupled to it. Arsanilic acid, sulphanilic acid and para-amino-benzoic acid were used as haptens. Precipitation and passive haemagglutination were used to demonstrate the presence of antibody. Only one size of antibody could be demonstrated to all antigens (13.2S(20)). Two populations of antibody could be demonstrated by the use of electrophoresis, and both populations of antibody reacted with BSA in fish receiving only BSA. In fish receiving BSA-hapten, the BSA antibody was found in the slower migrating population, while the haptenic antibody was found in the faster migrating population. The fish antibodies to all immunogens were poor precipitins, but gave titres similar to rabbit antibody when tested by passive haemagglutination. The specificity of fish protein and haptenic antibody is similar to rabbit antibody.