Markers of platelet activation and apoptosis in platelet concentrates collected by apheresis.

BACKGROUND: A product with well-preserved haemostatic function of platelets is the ultimate goal of platelet concentrate production. However, platelet activation and apoptosis are induced by both collection and storage of platelet concentrates. AIM OF STUDY: Platelet concentrates obtained either by two blood separators with different technology of apheresis (Haemonetics MCS+, Haemonetics Corp. Braintree, USA and Trima Accel, Gambro BCT Inc., Lakewood, USA, respectively) or derived from buffy-coat were compared using evaluation of pH, LDH, lactate, glucose, annexin V, and sP-selectin levels immediately after collecting and at the end of expiration to estimate the differences in the activation and apoptosis of platelets in these products. RESULTS: The lowest degree of platelet activation was found in products obtained by Haemonetics MCS+ apparatus at the time of collection. Platelet concentrates obtained by apheresis revealed higher rise of LDH, annexin V and sP-selectin compared to buffy-coat derived platelets. Products from Haemonetics MCS+ showed higher rise of annexin V in comparison with products from Trima separator. Increase of LDH and sP-selectin in both apheresis products was comparable. CONCLUSIONS: On the basis of changes of sP-selectin and annexin V levels it could be concluded that initial platelet activation, which is induced by apheresis, is very likely without any further impact on quality of platelets during storage. Development of platelet storage lesions is influenced especially by storage conditions and platelet concentration in products.