Antibody Inhibition by a Minimal Dose of Antigen and Response to a Sudden Increase of the Dose

Abstract

WE have already demonstrated^1–3 that continued administration of an optimal level of an antigenic stimulus to an adult animal finally produces a considerable decrease or even a disappearance of circulating antibodies (≃ 400 days). The inhibition applies to complete as well as to incomplete antibodies; it is specific, that is to say, the animal responds normally to another antigenic stimulus, and it is accompanied by a very poor cytological response³. As the phenomenon is produced by relatively small doses of antigen, in contrast to ‘immunological paralysis’, it is appropriate for testing the response of the inhibited animal to a sudden increase in the antigenic dose. Animals inhibited to Brucella abortus show a small but significant increase in antibody, after the injection of a large antigenic dose^2,3. This communication presents the results of our investigations of this phenomenon in the rabbit using human erythrocytes.