Platelet adhesive dynamics. Part I: Characterization of platelet hydrodynamic collisions and wall effects
Platelet adhesive dynamics. Part I: Characterization of platelet hydrodynamic collisions and wall effects
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DOI：
10.1529/biophysj.107.127670
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发表时间：
2008-09-01
影响因子：
3.4
通讯作者：
King, Michael R.
中科院分区：
文献类型：
--
作者：
Mody, Nipa A.;King, Michael R.
即使在没有血管损伤的情况下，体内遇到的异常高剪切应力也会诱导血小板自发激活和聚集体的形成。一个三维的多尺度计算模型血小板粘附动力学的开发和应用在第一部分和第二部分的文章，以阐明GPIb α-冯-维勒布兰德因子介导的血小板间结合的特征剪切诱导的血小板聚集的发病的关键生物物理方面。在这篇文章中，流体动力学效应的扁球体形状的血小板和接近的一个平面壁的细胞-细胞碰撞的性质进行了系统的研究。表征两个血小板之间的近壁接触的整个范围内的碰撞血小板表面之间的粘附概率的物理量获得的应用程序中的血小板粘附动力学模拟的血小板聚集探索的配套文章。还描述了将血小板间结合效率的模拟预测与实验确定的效率相匹配的技术。血小板碰撞行为被发现是惊人的不同，从球体，无论是接近和远离边界墙。我们的研究结果传达了显着的效果，颗粒形状和存在的边界壁上的颗粒轨迹和碰撞机制，碰撞特性，如碰撞时间和接触面积，碰撞频率。
Abnormally high shear stresses encountered in vivo induce spontaneous activation of blood platelets and formation of aggregates, even in the absence of vascular injury. A three-dimensional multiscale computational model-platelet adhesive dynamics-is developed and applied in Part I and Part II articles to elucidate key biophysical aspects of GPIb alpha-von-Willebrand-factor-mediated interplatelet binding that characterizes the onset of shear-induced platelet aggregation. In this article, the hydrodynamic effects of the oblate spheroidal shape of platelets and proximity of a plane wall on the nature of cell-cell collisions are systematically investigated. Physical quantities characterizing the adhesion probabilities between colliding platelet surfaces for the entire range of near-wall encounters between two platelets are obtained for application in platelet adhesive dynamics simulations of platelet aggregation explored in a companion article. The technique for matching simulation predictions of interplatelet binding efficiency to experimentally determined efficiencies is also described. Platelet collision behavior is found to be strikingly different from that of spheres, both close to and far from a bounding wall. Our results convey the significant effects that particle shape and presence of a bounding wall have on the particle trajectories and collision mechanisms, collision characteristics such as collision time and contact area, and collision frequency.