Release of autocrine growth factor by primary and immortalized Schwann cells.
Release of autocrine growth factor by primary and immortalized Schwann cells.
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DOI：
10.1073/pnas.84.21.7768
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发表时间：
1987-11
影响因子：
11.1
通讯作者：
S. Porter;L. Glaser;R. Bunge
中科院分区：
文献类型：
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作者：
S. Porter;L. Glaser;R. Bunge
来自新生大鼠坐骨神经的雪旺细胞在培养中是静止的，除非用特定的有丝分裂原处理。使用胶质生长因子（GGF）和福斯克林是一种有效的方法，可以刺激雪旺细胞在聚赖氨酸（l -赖氨酸）基质上的增殖，同时保持其体外轴突髓鞘化的能力。我们发现，雪旺细胞与GGF和forskolin的重复传代导致正常生长控制的丧失；细胞能够在没有添加有丝分裂原的情况下增殖。永生化细胞在没有添加生长因子和血清存在或不存在的情况下持续生长，但仍继续表达独特的雪旺细胞表面抗原。在培养过程中，细胞可与轴突结合，形成基底层和鞘轴突，但逐渐丧失形成髓鞘轴突的能力。永生化细胞将促进生长的活性释放到培养基中。释放的活性有效地刺激原代雪旺细胞的增殖，保持正常的生长特性。细胞外基质分子（层粘连蛋白和纤维连接蛋白）增强了原代雪旺细胞对分泌丝裂原的反应。静止的原代雪旺细胞也会在培养基中分泌一种生长因子，但其活性只有在添加层粘连蛋白或纤维连接蛋白的情况下才能检测到。结果表明，正常和永生化的雪旺细胞均分泌一种自分泌生长因子。对自分泌因子的反应似乎需要一个多组分机制。与原代细胞不同，永生化雪旺细胞有能力分泌所有必要的成分，并对它们作出反应。
Schwann cells derived from neonatal rat sciatic nerve are quiescent in culture unless treated with specific mitogens. The use of glial growth factor (GGF) and forskolin has been found to be an effective method for stimulating proliferation of Schwann cells on a poly(L-lysine) substratum while maintaining their ability to myelinate axons in vitro. We find that repetitive passaging of Schwann cells with GGF and forskolin results in the loss of normal growth control; the cells are able to proliferate without added mitogens. The immortalized cells grow continuously in the absence of added growth factor and in the presence or absence of serum yet continue to express distinctive Schwann cell-surface antigens. The cells can associate with axons in culture, deposit a basal lamina, and ensheath axons, but they gradually lose their capacity to myelinate axons. The immortalized cells release growth-promoting activity into their culture medium. The released activity is effective in stimulating proliferation of primary Schwann cells that retain normal growth properties. Extracellular matrix molecules (laminin and fibronectin) augment the response of primary Schwann cells to the secreted mitogen. Quiescent primary Schwann cells also secrete a growth factor into their culture medium, but its activity is detectable only in the presence of added laminin or fibronectin. The results suggest that both normal and immortalized Schwann cells secrete an autocrine growth factor. Response to the autocrine factor appears to entail a multicomponent mechanism. Unlike primary cells, immortalized Schwann cells have the capacity to secrete all of the necessary components and to respond to them constitutively.