Wee Hyun, Oh Hyun-Mee, Jo Jae-Hyeok, Jun Chang-Duk
Department of Life Science, Cell Dynamics Research Center, BioImaging Research Center, Research Center for Biomolecular Nanotechnology, Gwangju Institute of Science and Technology, Korea.
Exp Mol Med. 2009 May 31;41(5):341-8. doi: 10.3858/emm.2009.41.5.038.
The basic route and mechanism for diapedesis has not yet to be fully defined. Here we present evidence that "cell-cell separation" between endothelial cells (ECs) may provide a route for leukocyte diapedesis. We unexpectedly found that extensive interaction between peripheral blood leukocytes and ECs that were activated by TNF-alpha induced the opening of EC contacts and, surprisingly, resulted in cell-cell separation. This event was specific to the intercellular adhesion molecules-1 (ICAM-1)/leukocyte function- associated antigen-1 interaction, as demonstrated by the following: (1) ICAM-1 expression correlated with increased EC contraction; and (2) the blocking of ICAM-1 selectively inhibited EC separation. Thus, we suggest that "cell-cell separation" could be a mechanism for diapedesis in situations that may require massive leukocyte infiltration.
白细胞渗出的基本途径和机制尚未完全明确。在此，我们提供证据表明内皮细胞（ECs）之间的“细胞-细胞分离”可能为白细胞渗出提供一条途径。我们意外地发现，外周血白细胞与被肿瘤坏死因子-α激活的内皮细胞之间的广泛相互作用诱导了内皮细胞连接的开放，并且令人惊讶的是，导致了细胞-细胞分离。如下所示，该事件对于细胞间黏附分子-1（ICAM-1）/白细胞功能相关抗原-1相互作用具有特异性：（1）ICAM-1表达与内皮细胞收缩增加相关；（2）ICAM-1的阻断选择性地抑制了内皮细胞分离。因此，我们认为在可能需要大量白细胞浸润的情况下，“细胞-细胞分离”可能是一种渗出机制。
