Novel analytical measures are needed to accurately monitor the properties of platelet concentrates (PCs). Since activated platelets produce platelet-derived extracellular vesicles (EVs), analyzing EVs of PCs may provide additional information about the condition of platelets. The prospect of using EVs as an auxiliary measure of platelet activation state was investigated by examining the effect of platelet additive solutions (PASs) on EV formation and platelet activation during PC storage. The time-dependent activation of platelets in PCs with PAS-B or with the further developed PAS-E was compared by measuring the exposure of CD62P by flow cytometry and the content of soluble glycoprotein V (sGPV) of PCs by an immunoassay. Changes in the concentration and size distribution of EVs were determined using nanoparticle tracking analysis. A time-dependent increase in platelet activation in PCs was demonstrated by increased CD62P exposure, sGPV content, and EV concentration. Using these strongly correlating parameters, PAS-B platelets were shown to be more activated compared to PAS-E platelets. Since the EV concentration correlated well with the established platelet activation markers CD62P and sGPV, it could potentially be used as a complementary parameter for platelet activation for PCs. More detailed characterization of the resulting EVs could help to understand how the PC components contribute the functional effects of transfused PCs.

中文翻译：

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使用细胞外囊泡、CD62P 暴露和具有两种不同血小板添加剂溶液的血小板浓缩物的可溶性糖蛋白 V 含量评估时间依赖性血小板活化

需要新的分析措施来准确监测血小板浓缩物 (PC) 的特性。由于活化的血小板会产生血小板衍生的细胞外囊泡 (EV)，因此分析 PC 的 EV 可能会提供有关血小板状况的额外信息。通过检查血小板添加剂溶液 (PAS) 在 PC 储存过程中对 EV 形成和血小板活化的影响，研究了使用 EV 作为血小板活化状态的辅助措施的前景。通过流式细胞术测量 CD62P 的暴露和免疫测定法测量 PC 的可溶性糖蛋白 V (sGPV) 的含量，比较了 PAS-B 或进一步开发的 PAS-E 的 PC 中血小板的时间依赖性激活。使用纳米粒子跟踪分析确定 EV 浓度和尺寸分布的变化。增加的 CD62P 暴露、sGPV 含量和 EV 浓度证明了 PC 中血小板活化的时间依赖性增加。使用这些强相关参数，与 PAS-E 血小板相比，PAS-B 血小板显示出更高的激活。由于 EV 浓度与已建立的血小板活化标志物 CD62P 和 sGPV 相关性良好，因此它有可能用作 PC 血小板活化的补充参数。对由此产生的 EV 进行更详细的表征可能有助于了解 PC 组件如何影响输血 PC 的功能效果。由于 EV 浓度与已建立的血小板活化标志物 CD62P 和 sGPV 相关性良好，因此它有可能用作 PC 血小板活化的补充参数。对由此产生的 EV 进行更详细的表征可能有助于了解 PC 组件如何影响输血 PC 的功能效果。由于 EV 浓度与已建立的血小板活化标志物 CD62P 和 sGPV 相关性良好，因此它有可能用作 PC 血小板活化的补充参数。对由此产生的 EV 进行更详细的表征可能有助于了解 PC 组件如何影响输血 PC 的功能效果。