Fang Ying, Wu Jianhua, McEver Rodger P, Zhu Cheng
Institute of Biomechanics and School of Bioscience and Bioengineering, South China University of Technology, Guangzhou 510006, China.
J Biomech. 2009 Feb 9;42(3):303-7. doi: 10.1016/j.jbiomech.2008.11.020. Epub 2009 Jan 13.
P-selectin is a cell adhesion molecule expressed on activated endothelial cells and platelets. P-selectin glycoprotein ligand 1 (PSGL-1) is a mucin expressed on leukocytes. The interaction of P-selectin and PSGL-1 mediates leukocyte tethering to and rolling on the vascular surface, which are initiating events in inflammatory and thrombotic processes. In the hemodynamic environment of the circulation, P-selectin and PSGL-1 are subject to a wide range of forces, which can cause deformation. For P-selectin/PSGL-1 interaction to be physically possible, these molecules may need to project above much of the glycocalyx layers of the respective cell surfaces, suggesting that they are either longer than the thickness of glycocalyx or better able to support compression than the glycocalyx. As such, the mechanical properties of these molecules and their functional implications merit investigation. Here we report determination of the bending rigidities of P-selectin and PSGL-1 by analyzing their thermally excited curvature fluctuations, whose values are of the order of magnitude of 100pNnm(2).
P-选择素是一种在活化内皮细胞和血小板上表达的细胞黏附分子。P-选择素糖蛋白配体1（PSGL-1）是一种在白细胞上表达的黏蛋白。P-选择素与PSGL-1的相互作用介导白细胞与血管表面的拴系和滚动，这是炎症和血栓形成过程中的起始事件。在循环的血流动力学环境中，P-选择素和PSGL-1会受到多种力的作用，这些力会导致它们变形。为了使P-选择素/PSGL-1相互作用在物理上成为可能，这些分子可能需要突出于各自细胞表面的大部分糖萼层之上，这表明它们要么比糖萼的厚度更长，要么比糖萼更能承受压缩。因此，这些分子的力学性质及其功能意义值得研究。在此，我们通过分析它们的热激发曲率波动来报告P-选择素和PSGL-1弯曲刚度的测定结果，其值约为100pNnm(2)量级。
