DOWN-REGULATION OF ADHESION MOLECULES DURING NEUTROPHIL CHEMOTAXIS

炎症部位的神经元动员是一个多步骤的过程， 涉及对特异性内皮细胞质膜的可逆粘附 分子，选择的中性粒细胞粘附分子在 化学引诱物暴露和通过内皮细胞的迁移（趋化性） 间隙和基底膜进入组织。 本研究 进行检查发生在粘附分子的变化， 在聚碳酸酯上体外中性粒细胞趋化过程中的表达 膜基质 选择聚碳酸酯膜系统用于 这项研究是因为：1）不像内皮细胞单层， 其粘附分子表达的变化，聚碳酸酯表面 在中性粒细胞粘附和活化期间保持相对恒定，并且 2)中性粒细胞的两个群体很容易识别和分离， 聚碳酸酯膜系统;一个种群不会迁移到 化学引诱物，并保持在膜的上表面，而 另一个种群通过膜孔迁移到下层 膜表面（化学反应性群体）。 中性粒细胞，在含或不含N-甲酰肽的悬浮液中孵育 （FMLP）35分钟，与化疗反应性 而无反应的亚群则暴露于 FMLP 35分钟 中性粒细胞被一组粘附物染色 分子单克隆抗体，识别：白细胞-细胞 粘附分子家族（Leu-CAM）、CD 11 a、CD 11b、CD 11 c和CD 18; 血小板/内皮细胞粘附分子-1（PECAM-1），CD 31;白唾液酸， CD 43;和归巢受体Pgp-1，CD 44。 的流式细胞术分析 该小组揭示， 一致下调这些粘附分子的表达。 CD 44、CD 43和CD 11 a的下调幅度最大; CD 11 c， CD 31和CD 11b中度下调; CD 18轻微下调。 监管. 与此相反，只有CD 43是一致的下调， 非粘附性，FMLP刺激的中性粒细胞。

Neutrophil mobilization to inflammatory sites is a multi-step process which involves the reversible adhesion to specific endothelial plasma membrane molecules, upregulation of selected neutrophil adhesion molecules during chemoattractant exposure, and migration (chemotaxis) through endothelial gaps and the basement membrane into tissues. The present study was undertaken to examine the changes that occur in adhesion molecular expression during neutrophil chemotaxis in vitro on a polycarbonate membrane substratum. The polycarbonate membrane system was selected for this study because: 1) unlike endothelial monolayers which have dynamic changes in their adhesion molecular expression, the polycarbonate surface remains relatively constant during neutrophil adherence and activation, and 2) two populations of neutrophils are easily identified and separated with the polycarbonate membrane system; one population does not migrate to chemoattractant and remains on the upper surface of the membrane, whereas the other population migrates through the membrane pores to the lower surface of the membrane (chemotactically responsive population). Neutrophils, incubated in suspension with or without the N-formyl peptide (FMLP) for 35 minutes, were compared with the chemotactically responsive and the nonresponsive subpopulations which were exposed to a gradient of FMLP for 35 minutes. Neutrophils were stained with a panel of adhesion molecule monoclonal antibodies which recognize: the leukocyte-cell adhesion molecular family (Leu-CAM), CD11a, CD11b, CD11c, and CD18; the platelet/endothelial cell adhesion molecule-1 (PECAM-1), CD31; leukosialin, CD43; and, the homing receptor Pgp-1, CD44. Flow cytometric analysis of the panel revealed that the chemotactically responsive subpopulation consistently down-regulated the expression of these adhesion molecules. CD44, CD43, and CD11a were the most dramatically down-regulated; CD11c, CD31, and CD11b were moderately down-regulated; and CD18 was slightly down- regulated. In contrast, only CD43 was consistently down-regulated on nonadherent, FMLP-stimulated neutrophils.