BIOSYNTHESIS OF ANTIBODY MOLECULES WITH SIMILAR PROPERTIES DURING PROLONGED IMMUNIZATION

Anti-p-azobenzoate antibodies of the immunoglobulin G class were purified specifically from pools of serum collected from individual rabbits at intervals of about 6 months. Recombinants were prepared in which heavy chains were derived from the earlier and light chains from the later bleedings of the same rabbit, as well as reciprocal recombinants in which heavy chains were obtained from the later bleedings and light chains from the earlier bleedings. Such recombinants possessed 60-100% as much specific activity as recombinants made from a single pool. Recombinants in which the light chains were derived from nonspecific immunoglobulin G or from anti-p-azobenzoate antibodies of other rabbits had much less activity. The results suggest prolonged persistence of cell lines synthesizing antibody molecules of a particular structure. Recovery of activity in both reciprocal recombinants, i.e., with the heavy chains coming from either the earlier or later pool and the light chains from the opposite pool, suggests persistence of both types of polypeptide chain. Since the animals were repeatedly challenged with antigen, it appears that the antigen was largely used to stimulate already committed cells in a hyperimmunized animal, rather than to initiate new clones. © 1969, American Chemical Society. All rights reserved.