胚胎干细胞的研究进展

胚胎干细胞（ESC）是来源于哺乳动物早期胚胎的内细胞团中的一种二倍体细胞，具有发育的全能性。ESC的体内和体外分化在分子水平有许多相似之处。在现有培养条件下。小鼠ESC体外分化的细胞类型或结构主要有4种：内皮细胞与血管，肌细胞和心肌、造血细胞和神经细胞，最近的研究提示；造血干细胞（HSC）来源于胚胎内的特定区域，HSC的产生可能受尚未发现的胚胎生长因子调节。ESC为从胚胎着手明确早期造血过程提供了方便有效的实验途径。人ESC的研究及应用尚面临一系列伦理问题，对ESC的研究具有广阔的应用前景。

Progress in Research on Embryonic Stem Cells

Embryonic stem cells are continuously growing stem cell lines of embryonic origin. The distinguishing features of ES cells are their capacity to be maintained in an undifferentiated state indefinitely in culture and their potential to develop into various kinds of cells in the body. At molecular level, in vivo and in vitro differentiation of ES cells are similar in many ways. To date, ES cells can differentiate in vitro into myocytes and myocardial cells, neural precursor cells, hematopoietic cells and endothelial cells. Recent evidence suggests that hematopoietic stem cells (HSCs) originate from a region within the embryo proper. It is likely that the genesis of HSCs is regulated by embryonic growth factors, which have not been discovered yet. ES cells have provided a convenient and effective experimental approach to define early hematopoietic process within embryos. Research on ES cells has broad application prospect.