Centre for Neuroscience, University of Melbourne, Parkville, Australia.
Stem Cells. 2010 Oct;28(10):1805-15. doi: 10.1002/stem.510.
Generation of mesencephalic dopamine (mesDA) neurons from human embryonic stem cells (hESCs) requires several stages of signaling from various extrinsic and intrinsic factors. To date, most methods incorporate exogenous treatment of Sonic hedgehog (SHH) to derive mesDA neurons. However, we and others have shown that this approach is inefficient for generating FOXA2+ cells, the precursors of mesDA neurons. As mesDA neurons are derived from the ventral floor plate (FP) regions of the embryonic neural tube, we sought to develop a system to derive FP cells from hESC. We show that forced expression of the transcription factor GLI1 in hESC at the earliest stage of neural induction, resulted in their commitment to FP lineage. The GLI1+ cells coexpressed FP markers, FOXA2 and Corin, and displayed exocrine SHH activity by ventrally patterning the surrounding neural progenitors. This system results in 63% FOXA2+ cells at the neural progenitor stage of hESC differentiation. The GLI1-transduced cells were also able to differentiate to neurons expressing tyrosine hydroxylase. This study demonstrates that GLI1 is a determinant of FP specification in hESC and describes a highly robust and efficient in vitro model system that mimics the ventral neural tube organizer.
从中胚层诱导多巴胺（mesDA）神经元需要来自各种外在和内在因素的几个阶段的信号。迄今为止，大多数方法都采用外源性处理 Sonic hedgehog（SHH）来诱导产生 mesDA 神经元。然而，我们和其他人已经表明，这种方法对于诱导 FOXA2+细胞（mesDA 神经元的前体）效率不高。由于 mesDA 神经元来源于胚胎神经管的腹侧基板（floor plate，FP）区域，我们试图开发一种从 hESC 中诱导产生 FP 细胞的系统。我们发现，在神经诱导的最早阶段强制表达转录因子 GLI1，会促使其向 FP 谱系分化。GLI1+细胞共表达 FP 标志物 FOXA2 和 Corin，并通过对周围神经祖细胞进行腹侧模式化表现出外分泌性 SHH 活性。该系统可使 hESC 神经祖细胞分化阶段的 FOXA2+细胞达到 63%。转导 GLI1 的细胞也能够分化为表达酪氨酸羟化酶的神经元。本研究表明，GLI1 是 hESC 中 FP 特异性的决定因素，并描述了一种高度稳健和高效的体外模型系统，可模拟腹侧神经管组织者。
