Wu Xia, Yan Rong, Zhao Li-Li, Dai Ke-Sheng
Jiangsu Institute of Haematology, The First Affiliated Hospital of Soochow University; Key Laboratory of Thrombosis and Hemostasis, Ministry of Health; Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215006, Jiangsu Province, China.
Jiangsu Institute of Haematology, The First Affiliated Hospital of Soochow University; Key Laboratory of Thrombosis and Hemostasis, Ministry of Health; Collaborative Innovation Center of Hematology, Soochow University, Suzhou 215006, Jiangsu Province, China . E-mail:
Zhongguo Shi Yan Xue Ye Xue Za Zhi. 2015 Aug;23(4):1069-74. doi: 10.7534/j.issn.1009-2137.2015.04.032.
This study was aimed to investigate the regulatory effect of protein disulfide isomerase (PDI) on platelet GPIbα ectodomain shedding.
The washed platelets were obtained from healthy volunteers. Platelets were incubated with PDI inhibitor bacitracin before stimulation with PMA (Phorbol-12-myristate-13-acetate), dibucaine and collagen. The N-terminal domain of GPIbα in supernatant was detected by Western blot, the GPIbα expression and the intraplatelet ROS levels were measured by flow cytometry.
neither GC content nor GPIbα expression was changed after the washed platelets from the healthy donors were incubated only with PDI inhibitor. The washed platelets were incubated with PDI inhibitor before stimulation with different stimulin, PMA, dibucaine or collagen, and then GPIbα was cleaved and ROS levels were elevated more than that in the controls.
PDI participates in the induced GPIbα ectodomein shedding, and the effect of PDI in this process maybe depend on the change of ROS level inside platelets. These results might provide a new point of view for the platelet drug development.
本研究旨在探讨蛋白二硫键异构酶（PDI）对血小板糖蛋白Ibα（GPIbα）胞外域脱落的调节作用。
从健康志愿者获取洗涤后的血小板。在用佛波醇12 - 肉豆蔻酸酯13 - 乙酸酯（PMA）、丁卡因和胶原刺激之前，将血小板与PDI抑制剂杆菌肽一起孵育。通过蛋白质印迹法检测上清液中GPIbα的N端结构域，通过流式细胞术测量GPIbα表达和血小板内活性氧（ROS）水平。
仅用PDI抑制剂孵育健康供体的洗涤后血小板后，GC含量和GPIbα表达均未改变。在用不同刺激物（PMA、丁卡因或胶原）刺激之前，将洗涤后的血小板与PDI抑制剂一起孵育，然后GPIbα被裂解，且ROS水平升高幅度大于对照组。
PDI参与诱导GPIbα胞外域脱落，且PDI在此过程中的作用可能取决于血小板内ROS水平的变化。这些结果可能为血小板药物研发提供新的视角。
