Laboratory of Molecular and Cell Biology, Institute of Biochemistry and Cell Biology, China.
J Cell Biochem. 2011 Apr;112(4):1022-34. doi: 10.1002/jcb.22962.
Induction of definitive endoderm (DE) cells is a prerequisite for the whole process of embryonic stem (ES) cells differentiating into hepatic or pancreatic progenitor cells. We have established an efficient method to induce mouse ES cell-derived DE cells in suspension embryonic body (EB) culture. Similar to previous studies, mouse ES cell-derived DE cells, which were defined as Cxcr4(+) c-Kit(+) , Cxcr4(+) E-cadherin(+) cells or Cxcr4(+) PDGFRa(-) cells, could be induced in the serum-free EBs at Day 4 of induction. The activations of Wnt, Nodal, and FGF signaling pathways in differentiating EBs promoted DE cell differentiation, while activation of BMP4 signaling inhibited the process. In the present study, we found that chemical activation of canonical Wnt signaling pathway by LiCl could synergize with Activin A-mediated Nodal signaling pathway to promote induction of DE cells, and inhibition of Bmp4 signaling by Noggin along with Activin A/LiCl further improved the efficiency of DE cell differentiation. The derived DE cells were proved for their capacities to become hepatic progenitor cells or pancreatic progenitor cells. In conclusion, we significantly improved the efficiency of generating mouse ES cell-derived DE cells by combined Activin A/LiCl/Noggin treatment. Our work will be greatly helpful to generate ES cell-derived hepatic cells and ES cell-derived pancreatic cells for future regenerative medicine.
诱导终末内胚层（DE）细胞是胚胎干细胞（ES）分化为肝或胰腺祖细胞的整个过程的前提。我们已经建立了一种在悬浮胚胎体（EB）培养中诱导小鼠 ES 细胞衍生的 DE 细胞的有效方法。与以前的研究类似，在诱导的第 4 天，在无血清 EBs 中可以诱导出被定义为 Cxcr4(+) c-Kit(+)、Cxcr4(+) E-cadherin(+)细胞或 Cxcr4(+) PDGFRa(-)细胞的小鼠 ES 细胞衍生的 DE 细胞。分化 EBs 中 Wnt、Nodal 和 FGF 信号通路的激活促进了 DE 细胞的分化，而 BMP4 信号通路的激活则抑制了该过程。在本研究中，我们发现 LiCl 对经典 Wnt 信号通路的化学激活可以与 Activin A 介导的 Nodal 信号通路协同作用，促进 DE 细胞的诱导，并且 Noggin 与 Activin A/LiCl 联合抑制 Bmp4 信号通路进一步提高了 DE 细胞分化的效率。所得到的 DE 细胞被证明能够成为肝祖细胞或胰腺祖细胞。总之，我们通过联合使用 Activin A/LiCl/Noggin 处理显著提高了生成小鼠 ES 细胞衍生的 DE 细胞的效率。我们的工作将极大地有助于生成用于未来再生医学的 ES 细胞衍生的肝细胞和 ES 细胞衍生的胰腺细胞。
