Department of Developmental Biology and Cancer Research, The Institute for Medical Research Israel-Canada, The Hebrew University-Hadassah Medical School, Jerusalem 91120, Israel.
European Research Institute for the Biology of Ageing, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, AV Groningen 9713, the Netherlands.
Cell Stem Cell. 2015 Nov 5;17(5):543-56. doi: 10.1016/j.stem.2015.08.006. Epub 2015 Sep 24.
Induced pluripotent stem cells (iPSCs) undergo extensive nuclear reprogramming and are generally indistinguishable from embryonic stem cells (ESCs) in their functional capacity and transcriptome and DNA methylation profiles. However, direct conversion of cells from one lineage to another often yields incompletely reprogrammed, functionally compromised cells, raising the question of whether pluripotency is required to achieve a high degree of nuclear reprogramming. Here, we show that transient expression of Gata3, Eomes, and Tfap2c in mouse fibroblasts induces stable, transgene-independent trophoblast stem-like cells (iTSCs). iTSCs possess transcriptional profiles highly similar to blastocyst-derived TSCs, with comparable methylation and H3K27ac patterns and genome-wide H2A.X deposition. iTSCs generate trophoectodermal lineages upon differentiation, form hemorrhagic lesions, and contribute to developing placentas in chimera assays, indicating a high degree of nuclear reprogramming, with no evidence of passage through a transient pluripotent state. Together, these data demonstrate that extensive nuclear reprogramming can be achieved independently of pluripotency.
诱导多能干细胞（iPSCs）经历广泛的核重编程，在功能能力和转录组以及 DNA 甲基化谱方面通常与胚胎干细胞（ESCs）无法区分。然而，细胞从一种谱系直接转化为另一种谱系通常会产生不完全重编程的、功能受损的细胞，这就提出了一个问题，即是否需要多能性来实现高度的核重编程。在这里，我们表明，在小鼠成纤维细胞中转染 Gata3、Eomes 和 Tfap2c 的瞬时表达会诱导稳定的、不依赖转染的滋养层干细胞样细胞（iTSCs）。iTSCs 具有与囊胚来源的 TSCs 高度相似的转录组，具有可比的甲基化和 H3K27ac 模式以及全基因组 H2A.X 沉积。iTSCs 在分化后产生滋养外胚层谱系，在嵌合体试验中形成出血性病变，并有助于胎盘的发育，表明高度的核重编程，没有证据表明其经过短暂的多能状态。总之，这些数据表明，广泛的核重编程可以独立于多能性来实现。
