Department of Genomic Science, Central University of Kerala, Kerala, India.
Institute for Stem Cell Research and Regenerative Medicine, Medical Faculty, Heinrich Heine University, Düsseldorf, Germany.
Reproduction. 2019 Sep;158(3):R97-R111. doi: 10.1530/REP-18-0083.
Pluripotency is the developmental potential of a cell to give rise to all the cells in the three embryonic germ layers, including germline cells. Pluripotent stem cells (PSCs) can be embryonic, germ cell or somatic cell in origin and can adopt alternative states of pluripotency: naïve or primed. Although several reports have described the differentiation of PSCs to extra-embryonic lineages, such as primitive endoderm and trophectoderm, this is still debated among scientists in the field. In this review, we integrate the recent findings on pluripotency among mammals, alternative states of pluripotency, signalling pathways associated with maintaining pluripotency and the nature of PSCs derived from various mammals. PSCs from humans and mouse have been the most extensively studied. In other mammalian species, more research is required for understanding the optimum in vitro conditions required for either achieving pluripotency or preservation of distinct pluripotent states. A comparative high-throughput analysis of PSCs of genes expressed in naïve or primed states of humans, nonhuman primates (NHP) and rodents, based on publicly available datasets revealed the probable prominence of seven signalling pathways common among these species, irrespective of the states of pluripotency. We conclude by highlighting some of the unresolved questions and future directions of research on pluripotency in mammals.
多能性是细胞产生所有三个胚胎生殖层细胞（包括生殖细胞）的发育潜能。多能干细胞（PSCs）可以来源于胚胎、生殖细胞或体细胞，并可以采用不同的多能状态：原始或初始。尽管有几个报告描述了 PSCs 向胚胎外谱系的分化，如原始内胚层和滋养外胚层，但这在该领域的科学家之间仍存在争议。在这篇综述中，我们整合了哺乳动物多能性、多能状态、与维持多能性相关的信号通路以及各种哺乳动物来源的 PSCs 的性质的最新发现。来自人类和小鼠的 PSCs 已得到最广泛的研究。在其他哺乳动物物种中，需要进行更多的研究以了解实现多能性或保存不同的多能状态所需的最佳体外条件。基于公开可用数据集，对人类、非人类灵长类动物（NHP）和啮齿动物的原始或初始状态的 PSCs 进行的基因表达的高通量比较分析表明，无论多能状态如何，这七个信号通路在这些物种中可能都很重要。最后，我们强调了哺乳动物多能性研究中一些未解决的问题和未来的研究方向。
