Suppression of delayed hypersensitivity in vitro by inhibition of protein synthesis.

Peritoneal cells from guinea pigs exhibiting delayed hypersensitivity are inhibited from migrating in vitro by specific antigen. This inhibition is prevented by the addition of puromycin to the culture medium. The amount of puromycin necessary to prevent the inhibition by antigen also suppressed the incorporation of C(14)-leucine into peritoneal cell protein. Additional evidence that the action of puromycin is due to its inhibition of protein synthesis has been obtained with analogues of puromycin; those that inhibit protein synthesis also prevent the action of antigen on the cells, while those analogues that do not inhibit protein synthesis have no effect. Actinomycin also prevents the inhibition of sensitive cells by antigen while chloramphenicol has no effect. The data indicate that the inhibition of sensitive cell migration by antigen requires active protein synthesis. The possible mechanisms by which inhibition of protein synthesis may influence the in vitro reactions of delayed hypersensitivity are discussed.