Junge S, Brenner B, Lepple-Wienhues A, Nilius B, Lang F, Linderkamp O, Gulbins E
Department of Physiology, University of Tuebingen, Germany.
Cell Signal. 1999 Apr;11(4):301-8. doi: 10.1016/s0898-6568(98)00068-0.
Leucocyte adhesion to endothelial cells is a tightly regulated process involving selectins, integrins and immunoglobulin-like proteins. Cell adhesion and communication are controlled by membrane dynamics like receptor capping. Capping of surface receptors is an ubiquitous mechanism but still not well understood. Employing immunofluorescence techniques, we demonstrate that L-selectin triggering results in receptor capping of the L-selectin molecules in lymphocytes. Using pharmacological inhibitors and genetic deficient cell lines we show that this process involves intracellular signalling molecules. L-Selectin capping seems to be independent on activation of p56lck-kinase, but requires the neutral sphingomyelinase, small G proteins and the cytoskeleton. Therefore, capping of L-selectin upon stimulation might play an important role in the very early phase of lymphocyte trafficking.
白细胞与内皮细胞的黏附是一个受到严格调控的过程，涉及选择素、整合素和免疫球蛋白样蛋白。细胞黏附和通讯由膜动力学如受体成帽来控制。表面受体成帽是一种普遍存在的机制，但仍未被充分理解。利用免疫荧光技术，我们证明L-选择素的触发会导致淋巴细胞中L-选择素分子的受体成帽。使用药理学抑制剂和基因缺陷细胞系，我们表明这个过程涉及细胞内信号分子。L-选择素成帽似乎不依赖于p56lck激酶的激活，但需要中性鞘磷脂酶、小G蛋白和细胞骨架。因此，刺激后L-选择素的成帽可能在淋巴细胞迁移的早期阶段发挥重要作用。
