Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran; Australian Centre for Blood Diseases, Monash University, Melbourne, Victoria 3004, Australia.
Blood Transfusion Research Center, High Institute for Research and Education in Transfusion Medicine, Tehran, Iran.
Thromb Res. 2017 Aug;156:101-104. doi: 10.1016/j.thromres.2017.06.016. Epub 2017 Jun 10.
Upon platelet stimulation with agonists, reactive oxygen species (ROS) generation enhances platelet activation and granule release. Whether ROS generation during platelet storage could be directly correlated with the expression of proinflammatory molecules and granule release has been investigated in this study.
PRP-platelet concentrates were subjected to flowcytometry analysis to assess the expression of platelet activation marker, P-selectin and CD40L during storage. Intracellular ROS generation was also detected in platelet by flowcytometry using dihydrorhodamine (DHR) 123. Through the dual staining, ROS production was analyzed in either P-selectin positive or negative populations.
ROS formation in platelet population was significantly increased by either TRAP (a potent agonist that induces granule release) or PMA (a classic inducer of ROS generation), while the effects of each agonists on P-selectin expression and ROS generation in platelets were comparable. Platelet storage was also associated with the increasing levels of ROS (day 0 vs. day 5; p<0.001) while this increasing pattern was directly correlated with the either expressed P-selectin or CD40L. In addition, in 5 day-stored platelets, samples with ROS levels above 40% showed significantly higher levels of P-selectin and CD40L expression. P-selectin negative population of platelet did not show significant amount of ROS.
Our data demonstrated decreased levels of important platelet pro-inflammatory molecules in stored platelets with lower levels of intraplatelet ROS. However, whether quenching of ROS generation during platelet storage can attenuate adverse transfusion reactions raised by platelet pro-inflammatory status is required to be further studied.
血小板被激动剂刺激后，活性氧（ROS）的产生会增强血小板的激活和颗粒释放。本研究旨在探讨血小板储存过程中 ROS 的产生是否与促炎分子的表达和颗粒释放直接相关。
将 PRP-血小板浓缩物进行流式细胞术分析，以评估储存过程中血小板活化标志物 P-选择素和 CD40L 的表达。还通过二氢罗丹明 123（DHR）通过流式细胞术检测血小板内 ROS 的产生。通过双重染色，分析 P-选择素阳性或阴性群体中的 ROS 产生。
TRAP（一种诱导颗粒释放的有效激动剂）或 PMA（一种经典的 ROS 生成诱导剂）均可显著增加血小板群体中 ROS 的形成，而每种激动剂对血小板 P-选择素表达和 ROS 生成的影响相当。血小板储存也与 ROS 水平的升高有关（第 0 天与第 5 天相比；p<0.001），而这种增加模式与表达的 P-选择素或 CD40L 直接相关。此外，在储存 5 天的血小板中，ROS 水平超过 40%的样本显示出显著更高水平的 P-选择素和 CD40L 表达。血小板 P-选择素阴性群体没有显示出明显的 ROS 量。
我们的数据表明，储存的血小板中重要的血小板促炎分子水平降低，同时伴有较低水平的血小板内 ROS。然而，在血小板储存过程中抑制 ROS 的产生是否可以减轻由血小板促炎状态引起的不良反应，还需要进一步研究。
