Inhibition of specific immune responses by feeding protein antigens.

A profound and long-lasting state of specific immune unresponsiveness may be induced in adult inbred mice given a single dose of protein immunogens--such as ovalbumin or hemocyanin--by the digestive route. The degree of unresponsiveness induced by intragastric exposure to ovalbumin could not be achieved by intravenous injection of deaggregated ovalbumin solutions across a wide range of doses. Unresponsiveness induced by intragastric exposure to hapten-protein conjugates is specific to the carrier protein.