Joannides Alexis, Gaughwin Phil, Schwiening Christof, Majed Henry, Sterling Jane, Compston Alastair, Chandran Siddharthan
Department of Clinical Neurosciences, University of Cambridge and Addenbrooke's Hospital, Cambridge, UK.
Lancet. 2004;364(9429):172-8. doi: 10.1016/S0140-6736(04)16630-0.
Neural stem cells are a potential source of cells for drug screening or cell-based treatments for neurodegenerative diseases. However, ethical and practical considerations limit the availability of neural stem cells derived from human embryonic tissue. An alternative source of human neural stem cells is needed; a source that is readily accessible, easily expanded, and reliably induced to a neural fate.
Dermis isolated from biopsy samples of adult human skin was cultured and expanded in the presence of the mitogens epidermal growth factor (EGF) and fibroblast growth factor 2 (FGF 2), and then by serum. We used immunocytochemical techniques, clonal analysis, and physiological characterisation to assess neural differentiation after the treatment of expanded cells with novel induction media.
Initial characterisation of skin samples confirmed the absence of nestin, a neural precursor marker. Sequential culture in EGF and FGF 2 followed by adherent expansion in serum, and re-exposure to mitogens in substrate-free conditions resulted in large numbers of nestin-positive/musashi-positive neural precursors. Subsequent exposure of these precursors to hippocampal-astrocyte-derived signals resulted in cells of neuronal morphology that had stable expression of markers of neuronal differentiation (neurofilament, beta tubulin). We also show the presence of voltage-dependent calcium transients, and demonstrate monoclonal neural potential.
We describe the isolation and characterisation of cells derived from adult human dermis that can be expanded for extended periods of time in vitro, while retaining inducible neural potential. The generation of almost limitless numbers of neural precursors from a readily accessible autologous adult human source provides a platform for further experimental studies and has potential therapeutic implications.
神经干细胞是用于药物筛选或神经退行性疾病细胞治疗的潜在细胞来源。然而，伦理和实际考虑因素限制了源自人类胚胎组织的神经干细胞的可用性。因此需要一种替代的人类神经干细胞来源；这种来源应易于获取、易于扩增，并能可靠地诱导分化为神经细胞。
从成人皮肤活检样本中分离出的真皮在有丝分裂原表皮生长因子（EGF）和成纤维细胞生长因子2（FGF 2）存在的情况下进行培养和扩增，然后用血清培养。我们使用免疫细胞化学技术、克隆分析和生理学特征分析来评估用新型诱导培养基处理扩增细胞后的神经分化情况。
皮肤样本的初步特征分析证实不存在神经前体标志物巢蛋白。在EGF和FGF 2中顺序培养，随后在血清中贴壁扩增，并在无底物条件下再次暴露于有丝分裂原，产生了大量巢蛋白阳性/马斯ashi阳性神经前体。这些前体随后暴露于海马星形胶质细胞衍生的信号中，产生了具有神经元分化标志物（神经丝、β微管蛋白）稳定表达的神经元形态细胞。我们还显示了电压依赖性钙瞬变的存在，并证明了单克隆神经潜能。
我们描述了从成人真皮中分离和鉴定的细胞，这些细胞可以在体外长时间扩增，同时保留可诱导的神经潜能。从易于获取的自体成人来源产生几乎无限数量的神经前体，为进一步的实验研究提供了一个平台，并具有潜在的治疗意义。
