Meade-Tollin L C, Van Noorden C J
University of Arizona College of Medicine, Department of Surgery, Tucson 85724, USA.
Acta Histochem. 2000 Aug;102(3):299-307. doi: 10.1078/S0065-1281(04)70037-9.
Migration of microvascular endothelial cells is an early and critical step in angiogenesis. Formation of branching and polygonal cellular aggregates by endothelial cells on matrigel has often been considered to be an in vitro model for angiogenesis, although formation of lumens has not always been confirmed. The dynamics of migration of living cells of a human dermal microvascular endothelial cell line (HMEC-1) on a reconstituted basement membrane matrix have been captured in real time using time lapse video microscopy. The cells exhibit periods of quiescence and directed rapid migration by formation of extensions towards a specific target cell. Cells repeatedly extend flexible protrusions from the cell body both within the plane of the matrix and out of the plane of the matrix into the incubation medium. Connections between protrusions and target cells are made frequently, but not all cells which start to form protrusions achieve connections with other cells. Some of these migrating cells which do not connect arrest before reaching the target, or arrest and retract to their origin. After formation of multicellular polygonal structures, the structures contract to form amorphous clusters of fused cells without visible effects on the underlying matrix. The study demonstrates that time lapse video microscopy is a simple but very useful approach to monitor the dynamics of movements which vary in speed and frequency during migration of living cells.
微血管内皮细胞的迁移是血管生成早期的关键步骤。内皮细胞在基质胶上形成分支状和多边形细胞聚集体，这一过程通常被视为血管生成的体外模型，尽管管腔形成并非总能得到证实。利用延时视频显微镜实时捕捉了人真皮微血管内皮细胞系（HMEC-1）活细胞在重组基底膜基质上的迁移动态。细胞表现出静止期，并通过向特定靶细胞形成延伸来进行定向快速迁移。细胞在基质平面内以及从基质平面伸出进入培养液中时，会反复从细胞体伸出灵活的突起。突起与靶细胞之间频繁建立连接，但并非所有开始形成突起的细胞都能与其他细胞建立连接。一些未建立连接的迁移细胞在到达靶细胞之前就停止迁移，或者停止迁移并缩回其起始位置。多细胞多边形结构形成后，这些结构收缩形成融合细胞的无定形簇，而对下方的基质没有明显影响。该研究表明，延时视频显微镜是一种简单但非常有用的方法，可用于监测活细胞迁移过程中速度和频率各异的运动动态。
