Evaluation of the function of lyophilized platelets

Objective To evaluate the in vitro function of lyophilized platelets which were treated with reversible activation-inhibitors,DMSO and trehalose,and then were frozen and desiccated.Methods After the lyophilization,platelets were rehydrated,expression of CD62p and PAC-1 and expressions of CD62p and Pac-1 induced by thrombin were measured as the indexes of platelet activation and reactivity.The maximal aggregation and SPAT were taken as the indexes of aggregation and pocoagulant function.Morphology and ultra structure of platelets were observed by Scanning and transmission Electron microscope.Results The thrombin induced maximal aggregation of the lyophilized platelets(79.0%) showed no significant difference from fresh platelets(86.2%),but the ADP or propylgallate induced aggregation of the lyophilized platelets were decreased by 49.34% and 26.25%,respectively.Thrombin induced CD62p re-expression of the lyophilized platelets was 50.88%,lower than that of the control group,and PAC-1 was 54.55%,similar to that of the control group.The procoagulant activity of the product had no significant difference from the control.Conclusion The aggregation and procoagulant functions of the recovered lyophilized platelets treated with reversible activation-inhibitors,DMSO and trehalose are not significant different from fresh platelets.