| Abstract: | The effects of diethylstilbestrol (DES) and estramustine phosphate (EMP) on delayed hypersensitivity response (DTH) to oxazolone in male mice were investigated using a radioisotopic ear method. DES significantly inhibited the ability to express a DTH response and was most effective when given during the effector phase of the reaction. EMP had no effects when the animals were exposed to the drug during the effector phase, while it resulted in a strong and dose-dependent depression of the DTH response when applied in the sensitization phase. Possible involvement of suppressor cells was investigated by pretreatment of animals with cyclophosphamide or by adoptive transfer of tentative suppressor cells from spleen, lymph nodes, or peritoneal cavity. However, no evidence of cellular or humoral suppressor factors induced by drug treatment was found. |
