McCarthy J B, Palm S L, Furcht L T
J Cell Biol. 1983 Sep;97(3):772-7. doi: 10.1083/jcb.97.3.772.
Laminin is a large (greater than 850-kdalton) glycoprotein that is localized within basement membranes. Recent work has indicated that this protein is present within the endoneurium of mouse sciatic nerve. Furthermore, it has been shown that a rat Schwannoma cell line, RN22F, produced laminin and that laminin promoted the attachment of these cells to bacterial plastic. This report presents evidence that RN22F cells migrate in vitro to laminin in a concentration-dependent fashion. Laminin was extracted from the mouse EHS tumor and purified by molecular sieve and heparin-agarose affinity chromatography. The migration of Schwannoma cells to laminin, as assessed in a microwell modified Boyden chamber, was inhibited in a dose-dependent manner by affinity-purified antilaminin antibody. Zigmond-Hirsch checkerboard analysis experiments indicated that laminin stimulated both random and directed movement of RN22F cells. Additionally, reversal of the laminin gradient in the chambers also stimulated RN22F migration in a concentration-dependent manner, suggesting that directed migration of RN22F cells was due to a substratum-bound laminin (haptotaxis) as opposed to cell movement in response to fluid-phase laminin (chemotaxis). Binding studies using [3H]laminin demonstrated that laminin bound to the filter surface under the assay conditions used, and support the contention that cells are migrating to substrate-bound material. Furthermore, RN22F cells were shown to migrate on filters coated with laminin in the absence of additional fluid-phase laminin. The magnitude of this response could be altered by changing the relative density of bound laminin. In contrast, fibronectin promoted only marginal migration of RN22F cells. Collectively, these observations indicate that haptotaxis may be a mechanism by which laminin may guide cells during development and raise the possibility that it may be involved in peripheral nervous system myelination.
层粘连蛋白是一种大分子（大于850千道尔顿）糖蛋白，定位于基底膜内。最近的研究表明，这种蛋白质存在于小鼠坐骨神经的神经内膜中。此外，已经证明大鼠雪旺氏细胞瘤细胞系RN22F能产生层粘连蛋白，并且层粘连蛋白能促进这些细胞附着于细菌塑料。本报告提供了证据表明RN22F细胞在体外以浓度依赖的方式向层粘连蛋白迁移。层粘连蛋白从小鼠EHS肿瘤中提取，并通过分子筛和肝素 - 琼脂糖亲和色谱法纯化。在改良的微孔博伊登小室中评估，雪旺氏细胞瘤细胞向层粘连蛋白的迁移受到亲和纯化的抗层粘连蛋白抗体的剂量依赖性抑制。齐格蒙德 - 赫希棋盘分析实验表明，层粘连蛋白刺激了RN22F细胞的随机运动和定向运动。此外，小室内层粘连蛋白梯度的反转也以浓度依赖的方式刺激了RN22F迁移，这表明RN22F细胞的定向迁移是由于基质结合的层粘连蛋白（趋触性），而不是对液相层粘连蛋白的细胞运动反应（趋化性）。使用[3H]层粘连蛋白的结合研究表明，在所用的测定条件下层粘连蛋白与滤膜表面结合，并支持细胞向底物结合物质迁移的观点。此外，已证明RN22F细胞在没有额外液相层粘连蛋白的情况下能在涂有层粘连蛋白的滤膜上迁移。这种反应的程度可以通过改变结合层粘连蛋白的相对密度来改变。相比之下，纤连蛋白仅促进RN22F细胞的少量迁移。总的来说，这些观察结果表明趋触性可能是层粘连蛋白在发育过程中引导细胞的一种机制，并增加了它可能参与周围神经系统髓鞘形成的可能性。
