King Michael R, Sumagin Ronen, Green Chad E, Simon Scott I
Department of Biomedical Engineering, University of Rochester, 601 Elmwood Avenue, Box 639, Rochester, NY 14642, USA.
Math Biosci. 2005 Mar;194(1):71-9. doi: 10.1016/j.mbs.2004.12.008.
The most common white blood cell is the neutrophil, which slowly rolls along the walls of blood vessels due to the coordinated formation and breakage of chemical selectin-carbohydrate bonds. We show that L-selectin receptors are rapidly redistributed to form a cap at one end of the cell membrane during rolling via selectins or chemotactic stimulation. This topography significantly alters the adhesive dynamics as demonstrated by computer simulations of neutrophils rolling on a carbohydrate selectin-ligand substrate under flow. It was found that neutrophils with a redistributed L-selectin cap roll on sialyl Lewis-x with a quasi-periodic motion, as characterized by relatively low velocity intervals interspersed with regular jumps in the rolling velocity. On average, neutrophils with redistributed L-selectin rolled at a lower velocity when compared with cells having a uniform L-selectin distribution of equal average density. We speculate on the possible biological implications that these differences in adhesion dynamics will have during the inflammatory response.
最常见的白细胞是中性粒细胞，由于化学选择素 - 碳水化合物键的协同形成和断裂，它会沿着血管壁缓慢滚动。我们发现，在通过选择素进行滚动或趋化刺激的过程中，L - 选择素受体会迅速重新分布，在细胞膜的一端形成一个帽状结构。这种拓扑结构显著改变了黏附动力学，正如中性粒细胞在流动状态下于碳水化合物选择素 - 配体底物上滚动的计算机模拟所示。研究发现，具有重新分布的L - 选择素帽的中性粒细胞在唾液酸化路易斯 - x上以准周期性运动滚动，其特征是在滚动速度中穿插着相对较低速度区间和规则的跳跃。平均而言，与具有相同平均密度的均匀L - 选择素分布的细胞相比，具有重新分布的L - 选择素的中性粒细胞滚动速度较低。我们推测了这些黏附动力学差异在炎症反应过程中可能具有的生物学意义。
