Hubrecht Institute, Uppsalalaan 8, Utrecht 3584CT, The Netherlands.
Trends Cell Biol. 2013 Sep;23(9):442-8. doi: 10.1016/j.tcb.2013.04.004. Epub 2013 May 17.
Embryonic stem cells (ESCs) are pluripotent stem cells derived from the inner cell mass (ICM) of blastocyst embryos. Although first characterized over 30 years ago, the ontology of these cells remains elusive. Identifying the in vivo counterpart of murine ESCs will be essential for the derivation of stable ESC lines from other species. Several hypotheses exist concerning the ontology of murine ESCs. Recent data demonstrate that ESCs emerge from a subpopulation of ICM cells that transit through a Blimp1-positive state, suggesting that perhaps a germ cell developmental program underlies ESC derivation and maintenance. Alternatively, the common dependence of ESCs and diapause embryos on the cytokine LIF (leukemia inhibitory factor) has been thought to signify that murine ESCs employ a diapause-like program for their maintenance of pluripotency. Here we review different hypotheses regarding the nature of murine ESCs and discuss their implications for human pluripotent stem cell biology.
胚胎干细胞（ESCs）是多能干细胞，来源于囊胚胚胎的内细胞团（ICM）。尽管这些细胞在 30 多年前就被首次描述，但它们的本体论仍然难以捉摸。鉴定小鼠 ESC 的体内对应物对于从其他物种中获得稳定的 ESC 系至关重要。关于小鼠 ESC 的本体论存在几种假设。最近的数据表明，ESC 来源于 ICM 细胞的一个亚群，该亚群通过 Blimp1 阳性状态转化，这表明 ESC 的衍生和维持可能基于生殖细胞发育程序。或者，ESC 和休眠胚胎对细胞因子 LIF（白血病抑制因子）的共同依赖性被认为表明，小鼠 ESC 采用休眠样程序来维持其多能性。在这里，我们回顾了关于小鼠 ESC 本质的不同假设，并讨论了它们对人类多能干细胞生物学的影响。
