Platelet storage lesion: formation of platelet fragments with platelet factor 3 activity

Certain samples of stored platelet concentrates exhibited marked platelet factor 3 activity. This activity was associated almost completely with platelet fragments formed during storage. Platelet concentrates containing high levels of these fragments and hence high platelet factor 3 activity were characterized after storage by alkaline plasma pH values, high levels of extracellular lactate dehydrogenase activity and relatively low cell counts.