Conditions for the Enhancing Effect of Protease Inhibitors on the Concanavalin A Induced Thymidine Response of Murine Lymphocytes

Incorporation of [<sup>3</sup>H]-thymidine – [<sup>3</sup>H]-TdR – into concanavalin A (Con A) stimulated murine splenocytes and thymocytes was found to be enhanced by addition of certain concentrations of phenyl-methyl-sulfonylfluoride (PMSF), di-isopropylfluorophosphate (DFP), N-α-tosyl-<i>L</i>-lysyl-<i>L</i>-chloromethylketone (TLCK), and soybean trypsin inhibitor (SBTI). No enhancement could be observed when mononuclear cells of the peripheral blood were used, and a medium enhancement when thymocytes were applied. Furthermore, no enhancing effect of the protease inhibitors (PI) on the Con A response of murine splenocytes could be observed…