Agrawal M, Brauer P R
Department of Biomedical Sciences, Creighton University School of Medicine, Omaha, Nebraska 68178, USA.
Dev Dyn. 1996 Nov;207(3):281-90. doi: 10.1002/(SICI)1097-0177(199611)207:3<281::AID-AJA5>3.0.CO;2-D.
Proper migration and differentiation of neural crest (NC) cells are required for normal development of craniofacial structures, heart and great vessels, sensory and autonomic nervous systems, and other organs with vertebrate embryos. Serine-protease inhibitors reduce NC cell migration in vitro, suggesting the extracellular proteases are important mediators of NC cell migration. While plasminogen activator activity levels are high in NC cells relative to other embryonic tissue, its ability to regulate NC cell migration has not been specifically tested in vivo or in vitro through its ability to convert plasminogen to plasmin. Using a transfilter migration assay, NC cell migration was measured in the presence or absence of plasminogen. Our results showed that plasminogen significantly enhanced NC cell migration. This increase could not be attributed to differences in initial NC cell attachment or cytotoxicity and did not require a chemotactic gradient. The plasminogen-enhanced NC cell migration was blocked by aprotinin (a plasmin inhibitor) and was mimicked by the direct addition of plasmin to the NC cells, indicating that the plasminogen effect was mediated through plasmin generation. Furthermore, anticatalytic-uPA antibody blocked the plasminogen-enhanced NC cell migration showing that NC cell-associated uPA activity was required for this effect. Finally, decreasing NC-uPA activity by treating cells with transforming growth factor-Beta, also blocked the plasminogen-dependent increase in cell migration. These data show that in vitro, NC cell migration is regulated by NC-associated uPA activity suggesting that growth factor-regulation of this activity may play a major role in regulating NC cell migratory capacity in vivo.
神经嵴（NC）细胞的正确迁移和分化是脊椎动物胚胎颅面结构、心脏和大血管、感觉和自主神经系统以及其他器官正常发育所必需的。丝氨酸蛋白酶抑制剂可在体外减少NC细胞迁移，这表明细胞外蛋白酶是NC细胞迁移的重要介质。虽然相对于其他胚胎组织，NC细胞中的纤溶酶原激活物活性水平较高，但其调节NC细胞迁移的能力尚未通过其将纤溶酶原转化为纤溶酶的能力在体内或体外进行专门测试。使用跨膜迁移试验，在有或没有纤溶酶原的情况下测量NC细胞迁移。我们的结果表明，纤溶酶原显著增强了NC细胞迁移。这种增加不能归因于初始NC细胞附着或细胞毒性的差异，也不需要趋化梯度。纤溶酶原增强的NC细胞迁移被抑肽酶（一种纤溶酶抑制剂）阻断，并被直接向NC细胞中添加纤溶酶所模拟，这表明纤溶酶原的作用是通过纤溶酶的产生介导的。此外，抗催化型尿激酶型纤溶酶原激活物抗体阻断了纤溶酶原增强的NC细胞迁移，表明这种作用需要NC细胞相关的尿激酶型纤溶酶原激活物活性。最后，用转化生长因子-β处理细胞降低NC-尿激酶型纤溶酶原激活物活性，也阻断了纤溶酶原依赖性的细胞迁移增加。这些数据表明，在体外，NC细胞迁移受NC相关的尿激酶型纤溶酶原激活物活性调节，这表明该活性的生长因子调节可能在体内调节NC细胞迁移能力中起主要作用。
