Zwart Isabel, Hill Andrew J, Girdlestone John, Manca Maria F, Navarrete Roberto, Navarrete Cristina, Jen Ling-Sun
Department of Cellular and Molecular neuroscience, Imperial College, London, United Kingdom.
J Neurosci Res. 2008 Jul;86(9):1902-15. doi: 10.1002/jnr.21649.
We investigated the neurogenic potential of full-term human umbilical cord blood (hUCB)-derived multipotent mesenchymal stem cells (MSCs) in response to neural induction media or coculture with rat neural cells. Phenotypic and functional changes were assessed by immunocytochemistry, RT-PCR, and whole-cell patch-clamp recordings. Naive MSCs expressed both mesodermal and ectodermal markers prior to neural induction. Exposure to retinoic acid, basic fibroblast growth factor, or cyclic adenosine monophosphate (cAMP) did not stimulate neural morphology, whereas exposure to dibutyryl cAMP and 3-isobutyl-1-methylxanthine stimulated a neuron-like morphology but also appeared to be cytotoxic. All protocols stimulated increases in expression of the neural precursor marker nestin, but expression of mature neuronal or glial markers MAP2 and GFAP was not observed. Nestin expression increases were serum level dependent. Electrophysiological properties of MSCs were studied with whole-cell patch-clamp recordings. The MSCs possessed no ionic currents typical of neurons before or after neural induction protocols. Coculture of hUCB-derived MSCs and rat neural cells induced some MSCs to adopt an astrocyte-like morphology and express GFAP protein and mRNA. Our data suggest hUCB-derived MSCs do not transdifferentiate into mature functioning neurons in response to the above neurogenic protocols; however, coculture with rat neural cells led to a minority adopting an astrocyte-like phenotype.
我们研究了足月人脐带血（hUCB）来源的多能间充质干细胞（MSC）在神经诱导培养基作用下或与大鼠神经细胞共培养时的神经发生潜能。通过免疫细胞化学、逆转录-聚合酶链反应（RT-PCR）和全细胞膜片钳记录来评估表型和功能变化。未分化的MSC在神经诱导前同时表达中胚层和外胚层标志物。暴露于视黄酸、碱性成纤维细胞生长因子或环磷酸腺苷（cAMP）并未刺激神经形态的形成，而暴露于二丁酰cAMP和3-异丁基-1-甲基黄嘌呤则刺激了神经元样形态的形成，但似乎也具有细胞毒性。所有方案均刺激了神经前体标志物巢蛋白表达的增加，但未观察到成熟神经元或神经胶质标志物微管相关蛋白2（MAP2）和胶质纤维酸性蛋白（GFAP）的表达。巢蛋白表达的增加依赖于血清水平。用全细胞膜片钳记录研究了MSC的电生理特性。在神经诱导方案前后，MSC均不具有典型神经元的离子电流。hUCB来源的MSC与大鼠神经细胞共培养诱导一些MSC呈现星形胶质细胞样形态，并表达GFAP蛋白和mRNA。我们的数据表明，hUCB来源的MSC在上述神经发生方案作用下不会转分化为成熟的功能性神经元；然而，与大鼠神经细胞共培养导致少数细胞呈现星形胶质细胞样表型。
