Brezinschek R I, Oppenheimer-Marks N, Lipsky P E
Department of Internal Medicine, University of Texas Southwestern Medical Center, Dallas, TX 75235, USA.
J Immunol. 1999 Feb 1;162(3):1677-84.
Activated T cells acquire endothelial cell (EC) plasma membrane constituents during transendothelial migration. This was assessed using an in vitro model system in which human peripheral blood CD4+ T cells migrated through confluent monolayers of HUVEC. Flow cytometry of migrated CD4+ T cells demonstrated that activated, but not resting, T cells acquired a variety of endothelial surface determinants, including CD31, CD49d, CD54, CD61, and CD62E. The extracellular domains of these molecules were detected on migrated T cells with mAbs, including those directed to the ligand-binding regions. A number of approaches were employed to document that the acquisition of these molecules was uniquely accomplished by activated T cells and clearly involved transfer from both resting and TNF-alpha-activated EC. Acquisition of endothelial markers by activated T cells occurred as part of the transfer of membrane components, as migrating T cells acquired EC membranes prelabeled with the lipophilic dye, 3,3'-dihexadecyloxacarbocyanine perchlorate (DiOC-16), along with EC surface proteins. Thus, during transendothelial migration, activated T cells acquire endothelial membrane components, and as a result may deliver them to perivascular sites.
活化的T细胞在跨内皮迁移过程中获得内皮细胞（EC）的质膜成分。这是通过体外模型系统进行评估的，在该系统中，人外周血CD4+ T细胞穿过人脐静脉内皮细胞（HUVEC）的汇合单层。对迁移后的CD4+ T细胞进行流式细胞术分析表明，活化的而非静息的T细胞获得了多种内皮表面决定簇，包括CD31、CD49d、CD54、CD61和CD62E。用单克隆抗体（mAb）在迁移后的T细胞上检测到了这些分子的胞外结构域，包括那些针对配体结合区域的抗体。采用了多种方法来证明这些分子的获得是活化T细胞特有的过程，并且明确涉及来自静息和肿瘤坏死因子-α（TNF-α）活化的EC的转移。活化T细胞获得内皮标志物是膜成分转移的一部分，因为迁移的T细胞在获得EC表面蛋白的同时，还获得了用亲脂性染料3,3'-二己基氧杂羰花青高氯酸盐（DiOC-16）预标记的EC膜。因此，在跨内皮迁移过程中，活化的T细胞获得内皮膜成分，结果可能将它们递送至血管周围部位。
