Lawrence M B, Springer T A
Center for Blood Research, Boston, Massachusetts 02115.
Cell. 1991 May 31;65(5):859-73. doi: 10.1016/0092-8674(91)90393-d.
Rolling of leukocytes on vascular endothelial cells, an early event in inflammation, can be reproduced in vitro on artificial lipid bilayers containing purified CD62, a selectin also named PADGEM and GMP-140 that is inducible on endothelial cells. Neutrophils roll on this selectin under flow conditions similar to those found in postcapillary venules. Adhesion of resting or activated neutrophils through the integrins LFA-1 and Mac-1 to ICAM-1 in a lipid bilayer does not occur at physiologic shear stresses; however, static incubation of activated neutrophils allows development of adhesion that is greater than 100-fold more shear resistant than found on CD62. Addition of a chemoattractant to activate LFA-1 and Mac-1 results in the arrest of neutrophils rolling on bilayers containing both CD62 and ICAM-1. Thus, at physiologic shear stress, rolling on a selectin is a prerequisite for activation-induced adhesion strengthening through integrins.
白细胞在血管内皮细胞上滚动是炎症反应中的早期事件，这一过程可在体外含有纯化的CD62的人工脂质双分子层上重现。CD62是一种选择素，也被称为血小板内皮细胞黏附分子（PADGEM）和颗粒膜蛋白140（GMP-140），在内皮细胞上可被诱导表达。中性粒细胞在类似于毛细血管后微静脉中的流动条件下，在这种选择素上滚动。静息或活化的中性粒细胞通过整合素LFA-1和Mac-1与脂质双分子层中的细胞间黏附分子-1（ICAM-1）黏附，在生理剪切应力下不会发生；然而，活化的中性粒细胞进行静态孵育会形成黏附，其抗剪切能力比在CD62上的情况强100倍以上。添加趋化因子激活LFA-1和Mac-1会导致中性粒细胞在同时含有CD62和ICAM-1的双分子层上滚动停止。因此，在生理剪切应力下，在选择素上滚动是通过整合素激活诱导的黏附增强的前提条件。
