[Protective effects of DMSO on function of lyophilized human platelets]

This study was aimed to investigate the effects of DMSO on platelets during pre-treatment for lyophilization, including centrifugation, washing and loading trehalose. After pre-treatment for lyophilization, the expression of platelet membrane surface glycoprotein (GP) including CD62p and PAC-1 was analyzed by FCM before and after induction with thrombin, the mean platelet volume (MPV) and platelet maximal aggregation with several platelet inducers were investigated. The results showed that the expression rates of CD62p and PAC-1, as the platelet activation signs, increased and were 30.37% and 15.01% respectively in group without DMSO after pre-treatment. And their differences in comparison with control were statistically significant, but that of CD62p was 10.72% and PAC was 10.11% in group with DMSO, in comparison with group without DMSO respectively, their differences were statistically significant after diluting with DMSO, CD62p was re-expressed to 54.39% in group with DMSO and more than that in group without DMSO and lower than control statistically significant. PAC-1 was re-expressed to 49.28% in group with DMSO and more than that in group without DMSO (p<0.01) and reached to control. Platelet maximal aggregations induced by thrombin, restocetin and propyl gallate were 92.76%, 91.24% and 89.66 respectively in group with DMSO. These were closed to that in control group and in group without DMSO. But the aggregation induced by ADP was 34.33%, it was less than control (p<0.01) and more than that in group without DMSO (p<0.01). It is concluded that DMSO can inhibit the expression of CD62p and PAC-1 on platelet in vitro. But when diluted with plasma, platelets can express CD62p and PAC-1 induced by thrombin and be led to aggregate by several inducers, so the inhibitory effects of DMSO on platelet activation are reversible. DMSO play roles in inhibitor damage from platelet activation and cryoprotectant. This property of DMSO is very important in research of platelets lyophilization.