Suppressive effect of prednisolone on cytotoxicity of lymphocytes from normal persons against T24 cells.

While lymphocytes from normal persons exhibited cytotoxicity against T24 cells, prednisolone at a concentration as low as 10(-7) M significantly inhibited the cytotoxic reactions and almost complete inhibition was observed at the concentration of 10(-4) M. The inhibitory effect was shown to be progressively decreased when prednisolone was added during the cytotoxicity assay of normal human lymphocytes. These findings suggest that the cytotoxicity of lymphocytes from normal persons can be suppressed by immunosuppressive effect of prednisolone and that the early phase in the cytotoxic reaction is considerably sensitive to prednisolone.