Stewart H J, Eccleston P A, Jessen K R, Mirsky R
Department of Anatomy and Developmental Biology, University College London, England.
J Neurosci Res. 1991 Oct;30(2):346-52. doi: 10.1002/jnr.490300210.
Most previous studies on Schwann cell proliferation in vitro have used serum-containing media. This complicates the analysis of agents required for cell division since serum contains an ill-defined mixture of hormones and growth factors. Serum-free medium has therefore been used to analyse the response of Schwann cell to previously identified Schwann cell mitogens. Serum factors were not necessary for DNA synthesis in response to platelet-derived growth factor, basic fibroblast growth factor, or glial growth factor, provided they were used in combination with forskolin to elevate intracellular cAMP. Transforming growth factor beta 1, a Schwann cell mitogen in serum, was not mitogenic under these conditions. Neither the growth factors nor forskolin were effective when used alone. Growth control was analysed further using long-term cultured Schwann cells that had spontaneously immortalized. Measurements of endogenous cAMP levels in short- and long-term Schwann cells revealed that long-term cells had two to three times higher basal cAMP levels. As predicted by these findings, platelet-derived growth factor, basic fibroblast growth factor, and glial growth factor stimulated DNA synthesis in long-term cells without requiring costimulation by agents which elevate cAMP (while transforming growth factor beta 1 had no effect).(ABSTRACT TRUNCATED AT 250 WORDS)
以往大多数关于雪旺细胞体外增殖的研究都使用含血清培养基。这使得对细胞分裂所需因子的分析变得复杂，因为血清含有成分不明的激素和生长因子混合物。因此，无血清培养基已被用于分析雪旺细胞对先前确定的雪旺细胞促分裂原的反应。只要血小板衍生生长因子、碱性成纤维细胞生长因子或胶质生长因子与福斯高林联合使用以提高细胞内cAMP水平，血清因子对于DNA合成并非必需。在这些条件下，血清中的雪旺细胞促分裂原转化生长因子β1不具有促有丝分裂作用。单独使用生长因子或福斯高林均无效。使用自发永生化的长期培养雪旺细胞进一步分析生长控制。对短期和长期雪旺细胞内源性cAMP水平的测量显示，长期细胞的基础cAMP水平高出两到三倍。正如这些发现所预测的，血小板衍生生长因子、碱性成纤维细胞生长因子和胶质生长因子在长期细胞中刺激DNA合成，而无需通过提高cAMP的试剂进行共刺激（而转化生长因子β1没有作用）。（摘要截短于250字）
