贮存血小板形态变化与凋亡因子磷脂酰丝氨酸表达的研究

Morphology changes and the expression of phosphatidylserine in stored platelets

目的探讨储存期间机采血小板形态变化、凋亡因子磷脂酰丝氨酸(phosphatidyl serine,PS)表达以及两者之间的关系,为确立血小板体外保存时限提供实验依据。方法应用May-Grunwald-Giemsa染色方法观察机采血小板储存0-8d时的形态变化,同时应用流式细胞术检测血小板的膜PS表达率。结果储存至第4天,血小板形态出现损伤,表现为形态学计分与新鲜血小板相比显著下降(t=2.341,P<0.05);随着储存时间延长,血小板形态学计分持续下降,至第7天,形态学计分下降31%。血小板凋亡因子PS表达,储存1d组与新鲜血小板0d组相比有明显升高(t=3.088,P<0.05);储存1-3d,PS表达无明显变化,储存至第4天,PS表达显著增加(t=2.1612,P<0.05);储存5-8d,PS表达持续增加,各组间有统计学差异(P均<0.05)。血小板形态学变化分值与膜PS的表达随储存时间延长呈负相关性(r=-0.9923,P<0.01)。结论储存血小板形态学变化分值与膜PS表达率高度负相关。

Objective To study the morphology changes and the expression of phosphatidyl serine （PS） in apheresis platelets （Plts） during storage, also to analyze their relationship, in order to provide laboratorial evidence for the in vitro storage period of plts. Methods The morphological changes of plts during 8-day storage were detected by May-Grunwald-Giemsa dyeing method, and the expression of PS on platelet membrane was tested by flow cytometry （FCM）. Results The morphological lesions appeared on the fourth day of storage, because the modified morphological score （MMS） of 4-day group was significantly lower than that of fresh plts（ t = 2. 341, P 〈 0.05 ）. The MMS kept on decreasing with extended storage, and on the seventh day of storage, the MMS declined to 31%. However, the PS expression rate of 1-day storage group was obviously higher than that of 0-day group（ t = 3. 088, P 〈 0.05 ）. The PS expression showed no changes during 1-3 day storage, but increased markedly on the fourth day （ t = 2. 1612, P 〈 0.05 ）. During 5--8 day storage, the PS expression kept on increasing, and there were significant differences among groups （all P 〈0.05）. A negative correlation between MMS and PS expression rate was shown in stored pits（ r =-0. 9923, P〈0.01 ）. Conclusion There is a significant negative correlation between MMS and PS expression rate in stored Plts. The MMS index of stored Plts suggests that the storage time for apheresis Plts could be experimentally prolonged to 7 days.