The inhibition by cortisone of the cytotoxic activity of PPD on tuberculin-hypersensitive cells in tissue culture.

Using the roller tube method of tissue culture, it has been shown that cortisone and compound F inhibit the cytotoxic action of PPD upon macrophages from the splenic tissue of tuberculous guinea pigs. Pretreatment of the cells for 24 hours with hormones before exposure to PPD was found to be essential. Estrone and desoxycorticosterone glucoside had no protective activity. Certain advantages of the tissue culture method in studies of tuberculin hypersensitivity and possible mechanisms and implications of this protective action of cortisone are discussed.