In vitro evaluation of P-Selectin expression of platelet and platelet aggregation in stored platelet concentrates

Background and ObjectivesPlatelets have a major role in haemostasis. Platelet concentrates are used in thrombocytopeny and platelet dysfunction disorders. Due to recent studies reporting loss of in vivo function of platelets in platelet concentrate units, we determined the level of surface expression of P-Selectin, conducted platelet aggregation tests and pH measurment to evaluate platelet activation during storage.Materials and MethodsIn a cross-sectional study, 100 platelet concentrate units prepared by PRP method were evaluated. 34, 33 and 33 units were taken from the first, second, and third day of storage respectively. For each platelet concentrate unit, pH, CD62P-Selectin and platelet aggregation tests with Arashidonic acid and Ristocetin agonists were conducted.ResultsExpression of P-Selectin in third day was significantly higher than first day (p<0.05). Platelet aggregation tests showed significant decrease in third day compared to first day (p<0.05). pH in third day was significantly higher than first day (p<0.05).ConclusionsThe present study shows that activated platelets during 3 days of storage have increased P- Selectin on their surface. Therefore, the P-Selectin expression can be used as an in vivo marker for platelet activation function.