Quality study of cryopreserved platelet after being collected in different time point

Objetive:To study the quality of cryopreserved platelet after being collected in different time point.Methods:The platelets were preserved in-80℃ ultra cold freezer with 5% DMSO after being collected in 6,24,72 and 96 h.The platelets were thawed after three months.The blood platelets count(Plt) and mean platelet volume(MPV) were measured by automatic biochemical analyzer.Lactate dehydrogenase(LDH) was assayed by LDH kit and platelet glucoprotein CD62p was detected by flow cytometry.Results:The Plt、MPV、pH、LDH and CD62p of blood platelet showed no differences cryopreserved 6 h and 24 h after platelet collection compared with fresh blood platelet.However,the blood platelet cryopre served after 72 h and 96 h showed significantly increase in the biomarkers of Plt,MPV and LDH,and decrease of pH and the expression of CD62p compared with fresh blood platelet.Conclusion:The platelet can be activated after collection for a long time.In order to guarantee the blood platelet quality,the platelet should be cryopreserved as soon as possible after collection.