First Department of Physiology, Kawasaki Medical School, Kurashiki, Okayama, Japan.
J Physiol Sci. 2012 Jan;62(1):63-9. doi: 10.1007/s12576-011-0181-8. Epub 2011 Nov 23.
In response to atherogenic stimuli, blood monocytes transmigrate across the vascular endothelium not only through endothelial cell-cell junctions (para-cellular) but also through endothelial cells themselves (trans-cellular). The molecular mechanism of the latter is mostly unknown, because it rarely happens, especially in vitro. Although many reports have recognized trans-cellular migration from snapshot images of leukocytes halfway across the endothelium at non-junctional locations, it often produces a false-positive result, because some leukocytes that initiate trans-cellular migration withdraw and return to the apical endothelial surface. Thus, analyzing the entire process is essential. In this study, complete monocyte trans-cellular migration was successfully captured for live cells, with simultaneous visualization of endothelial PECAM-1. We suggest the possible existence of both PECAM-1-related migration at peri-junctional sites and PECAM-1-unrelated migration at sites remote from junctions. This is the first report to describe the entire process of monocyte trans-cellular migration for live cells and its relationship with endothelial PECAM-1.
针对动脉粥样硬化刺激，血液单核细胞不仅通过内皮细胞-细胞连接（旁细胞），而且通过内皮细胞本身（跨细胞）穿过血管内皮。后者的分子机制大部分是未知的，因为它很少发生，尤其是在体外。尽管许多报道已经从非连接位置的白细胞中途穿过内皮的快照图像中识别出跨细胞迁移，但它通常会产生假阳性结果，因为一些开始跨细胞迁移的白细胞会撤回并返回顶端内皮表面。因此，分析整个过程是至关重要的。在这项研究中，成功地为活细胞捕捉到完整的单核细胞跨细胞迁移，同时可视化内皮细胞 PECAM-1。我们建议在临近连接位点处可能存在与 PECAM-1 相关的迁移，而在远离连接位点处可能存在与 PECAM-1 无关的迁移。这是第一个描述活细胞中单核细胞跨细胞迁移的整个过程及其与内皮细胞 PECAM-1 的关系的报告。
