Suppression of delayed-type hypersensitivity in mice pretreated with diethylstilbesterol: involvement of sex hormones in immunomodulation.

Delayed-type hypersensitivity (DTH) responses were suppressed in female mice treated with diethylstilbesterol (DES), a synthetic nonsteroidal compound possessing estrogenic activity, but not in male mice. Upon analysis of this DTH-suppression in DES-treated female mice by use of the macrophage migration inhibition (MI) assay, an in vitro correlate of DTH, suppressor adherent cells (i.e., macrophages) in the peritoneal cavity were found to play an important role in this DTH suppression. On the other hand, DES-induced suppression was observed in surgically castrated male mice with depressed plasma testosterone (TS) levels, but not in TS-treated female mice or in castrated male mice, which suggests that TS inhibited the DES suppression. These results provide evidence that DTH response may be modulated by sex hormones.