Shenkman B, Savion N, Dardik R, Tamarin I, Varon D
Institute of Thrombosis and Hemostasis, Sheba Medical Center, Tel Hashomer, Tel Aviv, Israel.
Thromb Res. 2000 Aug 15;99(4):353-61. doi: 10.1016/s0049-3848(00)00255-3.
Recently, we described a method of testing platelet deposition on extracellular matrix under flow conditions. The method was used for assessment of platelet function in various platelet disorders, for monitoring of replacement and anti-platelet therapy. In the present study, we investigated platelet deposition on a polystyrene surface compared with that on extracellular matrix, under defined shear rates, using the original Cone and Plate(let) Analyzer. A correlation of adhesion rate (surface coverage) and aggregate formation (average size) of platelets from normal citrated blood between polystyrene and extracellular matrix was observed. Blocking of von Willebrand factor binding to glycoprotein Ib by a recombinant von Willebrand factor fragment substantially decreased platelet adhesion to both surfaces. Blocking of GPIIb-IIIa by Arg-Gly-Asp-Ser peptide prevented platelet adhesion to the polystyrene while an extensive adhesion of single platelets to extracellular matrix was observed. Furthermore, platelet adhesion to polystyrene but not to extracellular matrix was completely inhibited by platelet inactivation with prostaglandin E(1). Platelets from patients with severe von Willebrand disease yielded very low adhesion to both polystyrene and extracellular matrix. The addition of von Willebrand factor to the blood of these patients or pre-coating of polystyrene surface with von Willebrand factor restored the ability of platelets to adhere and aggregate on the surface. Platelets from patients with Glanzmann's thrombasthenia and afibrinogenemia adhered to extracellular matrix (with defective aggregate formation), while they failed to adhere to the polystyrene. Fibrinogen added to afibrinogenemia blood or pre-coating of the polystyrene with fibrinogen restored the ability of platelets to adhere and aggregate on the surface. In conclusion, the polystyrene surface, like extracellular matrix, can be used to assess platelet function disorders taking in account that platelet deposition on polystyrene under flow is absolutely dependent on platelet activation and on the presence of fibrinogen, von Willebrand factor, and their receptors.
最近，我们描述了一种在流动条件下测试血小板在细胞外基质上沉积的方法。该方法用于评估各种血小板疾病中的血小板功能，监测替代疗法和抗血小板治疗。在本研究中，我们使用原始的锥板（let）分析仪，在规定的剪切速率下，研究了血小板在聚苯乙烯表面与细胞外基质表面上的沉积情况。观察到正常枸橼酸盐血中血小板在聚苯乙烯和细胞外基质之间的黏附率（表面覆盖率）和聚集体形成（平均大小）具有相关性。重组血管性血友病因子片段阻断血管性血友病因子与糖蛋白Ib的结合，可显著降低血小板在两个表面的黏附。精氨酸-甘氨酸-天冬氨酸-丝氨酸肽阻断GPIIb-IIIa可防止血小板黏附于聚苯乙烯，而观察到单个血小板广泛黏附于细胞外基质。此外，用前列腺素E(1)使血小板失活可完全抑制血小板对聚苯乙烯的黏附，但对细胞外基质无抑制作用。重度血管性血友病患者的血小板对聚苯乙烯和细胞外基质的黏附都非常低。向这些患者的血液中添加血管性血友病因子或用血管性血友病因子预涂聚苯乙烯表面，可恢复血小板在表面黏附和聚集的能力。血小板无力症和无纤维蛋白原血症患者的血小板黏附于细胞外基质（聚集体形成有缺陷），但不黏附于聚苯乙烯。向无纤维蛋白原血症血液中添加纤维蛋白原或用纤维蛋白原预涂聚苯乙烯，可恢复血小板在表面黏附和聚集的能力。总之，聚苯乙烯表面与细胞外基质一样，可用于评估血小板功能障碍，前提是要考虑到流动状态下血小板在聚苯乙烯上的沉积绝对依赖于血小板激活以及纤维蛋白原、血管性血友病因子及其受体的存在。
