Department of Surgery (Neurosurgery), UMDNJ-Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
Stem Cells Dev. 2010 Sep;19(9):1343-53. doi: 10.1089/scd.2009.0520.
We describe a rapid and efficient 5-step program of defined factors for the genesis of brain myelin-forming oligodendrocytes (OLs) from embryonic stem cells (ESCs). The OLs emerge on the same time frame in vitro as seen in vivo. Factors promoting neural induction (retinoids, noggin) are required, while exogenous Sonic hedgehog is not. In contrast we were unable to generate OLs by trans-differentiation of ethically neutral mesenchymal stem cells, indicating a requirement for cis-differentiation via neural ectoderm for OL genesis. In the ESC-derived cultures, our optimized protocol generated a mixed population with 49% O4(+), Olig2(+) OL lineage cells. These cultures also retained pluripotential markers including Oct4, and an analysis of embryoid body formation in vitro, and allogeneic grafts in vivo, revealed that the ESC-derived cultures also retained teratogenic cells. The frequency of embryoid body formation from terminal differentiated OL cultures was 0.001%, 100-fold lower than that from ESCs. Our results provide the first quantitative measurement of teratogenicity in ESC-derived, exhaustively differentiated allogeneic grafts, and demonstrate the unequivocal need to purify ESC-derived cells in order to generate a safe population for regenerative therapy.
我们描述了一个快速而有效的 5 步程序，使用明确的因子从胚胎干细胞（ESCs）中生成脑髓鞘形成少突胶质细胞（OLs）。OLs 在体外出现的时间框架与体内所见相同。需要促进神经诱导的因子（视黄酸、noggin），而外源性 Sonic hedgehog 则不需要。相比之下，我们无法通过伦理中性的间充质干细胞的转分化来生成 OLs，这表明需要通过神经外胚层的顺式分化来生成 OL。在 ESC 衍生的培养物中，我们优化的方案生成了一个混合群体，其中 49%的细胞为 O4(+)、Olig2(+) OL 谱系细胞。这些培养物还保留了多能性标记物，包括 Oct4，并且对体外胚状体形成和体内同种异体移植物的分析表明，ESC 衍生的培养物也保留了致畸细胞。从终末分化的 OL 培养物中形成胚状体的频率为 0.001%，比从 ESCs 中形成的频率低 100 倍。我们的结果提供了 ESC 衍生的、耗尽分化的同种异体移植物中致畸性的第一个定量测量，并证明明确需要纯化 ESC 衍生的细胞，以生成用于再生治疗的安全细胞群体。
