Abbassi O, Kishimoto T K, McIntire L V, Smith C W
Biomedical Engineering Laboratory, Rice University, Houston, Texas.
Blood Cells. 1993;19(2):245-59; discussion 259-60.
The emigration of neutrophils at sites of inflammation apparently requires intercellular adhesion. Initially, leukocyte adherence is observed in postcapillary venules where neutrophils roll along the luminal surface of the endothelial cells before stopping, changing shape, and migrating into the perivascular tissue. Recent evidence indicates that the adhesion molecules supporting the rolling phenomenon are distinct from those required for stopping and transmigration. The contribution of E-selectin (ELAM-1) to neutrophil adhesion and rolling was investigated using anti-E-selectin monoclonal antibody in an in vitro adhesion assay of isolated human neutrophils to murine L-cell monolayers stably transfected with human E-selectin cDNA. Isolated human neutrophils adhered to E-selectin expressing L-cell monolayers under physiological wall shear stress of 1.85 dynes/cm2 but not to untransfected L-cells or ICAM-1 expressing L-cells. 47.8 +/- 6.0% of these adherent cells were rolling at an average rolling velocity of 10.6 +/- 1.7 microns/second. This adhesion and rolling was almost completely blocked by anti-E-selectin monoclonal antibody. Monoclonal antibody to L-selectin also reduced adhesion to E-selectin expressing cells by 70%. Chemotactic stimulation of neutrophils reduced both the number of adherent and rolling cells and the average velocity of the rolling cells without influencing the percentage of attached cells that were rolling. Pretreatment with anti-CD18 monoclonal antibody did not reduce the adhesion of the activated neutrophils but reversed the reduction in velocity caused by activation of these cells. The inhibitory potential of the anti-E-selectin monoclonal antibody was much less pronounced in adhesion of isolated neutrophils to human umbilical vein endothelial cell monolayers under conditions of flow and was limited to one third of the total adhesion. The proportion of the adherent neutrophils which transmigrated to the subluminal space of the endothelial cell monolayers was independent of pretreatment with anti-E-selectin monoclonal antibody.
中性粒细胞在炎症部位的移出显然需要细胞间黏附。最初，在毛细血管后微静脉中可观察到白细胞黏附，中性粒细胞在内皮细胞的管腔表面滚动，之后停止、改变形状并迁移至血管周围组织。最近的证据表明，支持滚动现象的黏附分子与停止和迁移所需的黏附分子不同。使用抗E-选择素单克隆抗体，在体外将分离的人中性粒细胞与稳定转染人E-选择素cDNA的鼠L细胞单层进行黏附试验，研究了E-选择素（ELAM-1）对中性粒细胞黏附和滚动的作用。在1.85达因/平方厘米的生理壁切应力下，分离的人中性粒细胞可黏附于表达E-选择素的L细胞单层，但不黏附于未转染的L细胞或表达ICAM-1的L细胞。这些黏附细胞中有47.8±6.0%以平均10.6±1.7微米/秒的滚动速度滚动。这种黏附和滚动几乎完全被抗E-选择素单克隆抗体阻断。抗L-选择素单克隆抗体也使对表达E-选择素细胞的黏附减少了70%。中性粒细胞的趋化刺激降低了黏附细胞和滚动细胞的数量以及滚动细胞的平均速度，但不影响黏附细胞中滚动细胞的百分比。用抗CD18单克隆抗体预处理不会降低活化中性粒细胞的黏附，但可逆转这些细胞活化导致的速度降低。在流动条件下，抗E-选择素单克隆抗体对分离的中性粒细胞与人脐静脉内皮细胞单层黏附的抑制作用不太明显，且仅限于总黏附的三分之一。迁移至内皮细胞单层管腔下空间的黏附中性粒细胞比例与抗E-选择素单克隆抗体预处理无关。
