Characteristics of the antigenic determinants revealed by hybridoma-made monoclonal antibodies against the Fc fragment of rabbit IgG

We studied 7 monoclonal antibodies produced by mouse hybridoma directed against the Fc fragment of rabbit IgG. Five of them recognized different antigenic determinants mostly borne by the CH3 domain. These antibodies seemed to distinguish some populations of IgG by precipitation in gel but not by radioimmunoadsorption. One monoclonal antibody probably recognized the e15 allotypic determinant. Some monoclonal antibodies recognized an ancestral isotypic determinant which has been preserved during evolution and is present on man, calf and rabbit IgG molecules.