Abstract The aim of this study was to search a procedure of plaet lyophilization and find a way of longterm sto rage of human plaets at normal temperature with smaller size and lighter weight, to be convenient to transport at long distance thus to meet the demands in accidents and war time. Human plaets were pretreated by freezing, the first and the second desiccation, and were added with reversible activationinhibitors of plaets, DMSO and trehalose, then were rehydrated. At the same time, the recovery rate of plaets, plaet maximal aggregation induced by thrombin, coagulation of plaets, CD62p expression and PAC1 expression were assayed. The results indicated that the recovery rate of the plalelets was 56.29%. The plaet maximal aggregation induced by thrombin had no significant difference between lyophilized plaets and the fresh plaetrich plasma (FPRP), but the aggregation of plaets induced by ADP or propyl gallate was decreased by 49.34% and 26.25%. Coagulation of the lyophilized plaets was not significantly different from FPRP. CD62p expression of the lyophilized plaets (42.36%) was higher than that in FPRP while PAC1 expression was 2.12%. CD62p reexpression rate induced by thrombin was 50.88% and PAC1 reexpression was 54.55%. It is concluded that the ability of recovered lyophilized plaets added with reversible activationinhibitors, DMSO and trehalose to aggregate and coagulate has showed no significant difference as compared with FPRP. The reversible activationinhibitors can decrease CD62p expression of lyophilized plaets, and may enhance their survival ability and prolongate survival time. Therefore the efficiency of lyophilizing plaets can be improved based on this freezedrying procedure.
Key words plaet; lyophilization; activationinhibitor; trehalose; DMSO