The use of inhibitors of platelet activation or protease activity in platelet concentrates stored for transfusion.

During storage of platelet concentrates the platelets show signs of activation, and extracellular protease activity becomes evident in the plasma. The consequences of platelet activation and plasma protease activity are potentially detrimental to the preservation of platelet function in vitro. The earlier use of prostaglandins during preparation of platelet concentrates to increase the harvest of platelets from whole blood did little to improve their shelf-life. Other compounds that sustain elevated cyclic AMP levels or that directly inhibit platelet agonists provide more effective inhibition of platelet activation during storage. Also, the inclusion of general or specific protease inhibitors appears to improve platelet preservation over extended storage periods. These studies demonstrate the possibility of prolonging the shelf-life of platelet concentrates stored at 22 degrees C through the addition of non-toxic formulations of inhibitors of platelet activation and protease activity.