Trzaska Katarzyna A, Kuzhikandathil Eldo V, Rameshwar Pranela
Graduate School of Biomedical Sciences, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, 185 South Orange Avenue, MSB E-585, Newark, New Jersey 07103, USA.
Stem Cells. 2007 Nov;25(11):2797-808. doi: 10.1634/stemcells.2007-0212. Epub 2007 Jul 26.
Dopamine (DA) neurons derived from stem cells are a valuable source for cell replacement therapy in Parkinson disease, to study the molecular mechanisms of DA neuron development, and for screening pharmaceutical compounds that target DA disorders. Compared with other stem cells, MSCs derived from the adult human bone marrow (BM) have significant advantages and greater potential for immediate clinical application. We report the identification of in vitro conditions for inducing adult human MSCs into DA cells. Using a cocktail that includes sonic hedgehog and fibroblast growth factors, human BM-derived MSCs were induced in vitro to become DA cells in 12 days. Based on tyrosine hydroxylase (TH) expression, the efficiency of induction was determined to be approximately 67%. The cells develop a neuronal morphology expressing the neuronal markers NeuN and beta III tubulin, but not glial markers, glial fibrillary acidic protein and Olig2. As the cells acquire a postmitotic neuronal fate, they downregulate cell cycle activator proteins cyclin B, cyclin-dependent kinase 2, and proliferating cell nuclear antigen. Molecular characterization revealed the expression of DA-specific genes such as TH, Pitx3, Nurr1, DA transporter, and vesicular monoamine transporter 2. The induced MSCs also synthesize and secrete DA in a depolarization-independent manner. The latter observation is consistent with the low expression of voltage gated Na(+) and Ca(2+) channels in the induced MSCs and suggests that the cells are at an immature stage of development likely representing DA neuronal progenitors. Taken together, the results demonstrate the ability of adult human BM-derived MSCs to form DA cells in vitro.
源自干细胞的多巴胺（DA）神经元是帕金森病细胞替代疗法、研究DA神经元发育分子机制以及筛选针对DA紊乱的药物化合物的宝贵来源。与其他干细胞相比，源自成人骨髓（BM）的间充质干细胞（MSCs）具有显著优势和更大的直接临床应用潜力。我们报告了诱导成人MSCs体外分化为DA细胞的条件。使用包含音猬因子和成纤维细胞生长因子的混合物，成人BM来源的MSCs在体外12天内被诱导成为DA细胞。基于酪氨酸羟化酶（TH）表达，诱导效率确定约为67%。这些细胞呈现出表达神经元标志物NeuN和βIII微管蛋白的神经元形态，但不表达胶质标志物胶质纤维酸性蛋白和少突胶质细胞转录因子2。随着细胞获得有丝分裂后神经元命运，它们下调细胞周期激活蛋白细胞周期蛋白B、细胞周期蛋白依赖性激酶2和增殖细胞核抗原。分子特征显示DA特异性基因如TH、Pitx3、Nurr1、DA转运体和囊泡单胺转运体2的表达。诱导的MSCs还以去极化非依赖方式合成和分泌DA。后一观察结果与诱导的MSCs中电压门控Na(+)和Ca(2+)通道的低表达一致，并表明这些细胞处于发育不成熟阶段，可能代表DA神经元祖细胞。综上所述，结果证明了成人BM来源的MSCs体外形成DA细胞的能力。
