Immunological properties of ampicillin polymers.

The immunologic effects of ampicillin polymers were studied in mice and rabbits. Polymerized ampicillin--in contrast to monomers--had a suppressive effect on the antibody response to penicilloylated proteins. Unfractionated ampicillin polymer, and high molecular weight fractions were found to have an immunogenic effect in mice, when tested by a haemolytic plaque assay. The immunogenic effect of variously sized polymers did not correspond to their antigenic activity as reflected by passive cutaneous anaphylaxis experiments.