人胚胎干细胞(human embryonic stem cells,hESCs)由囊胚期胚胎内细胞团分离培养获得,具有保持未分化状态的无限增殖能力。hESCs具有多向分化潜能,在体内和体外均可分化形成所有三个胚层(外胚层、中胚层、内胚层)的衍生物。hESCs一般在鼠胚胎成纤维细胞(mouse embryonic fibroblast,MEF)饲养层上培养和扩增。为了优化培养条件,目前人们已发展了多种人类细胞饲养层和无饲养层、非条件培养基体系。hESCs可以在体外定向诱导分化为多种细胞类型,为揭示人胚早期发育机制和发展多种疾病的细胞移植治疗奠定了基础。hESCs可以在体外进行遗传修饰,将有助于揭示特定基因在发育过程中的调控和功能。对hESCs的深入研究将极大地推动医学和生命科学的进展,并将最终应用于临床,造福人类。
Human embryonic stem cells (hESCs) can be derived from the inner cell mass of blastocyst embryo and propagate infinitely in an undifferentiated state. hESCs display pluripotency and can be differentiated into derivatives of all three embryonic germ layers (ectoderm, mesoderm and endoderm) both in vitro and in vivo. Generally hESCs culture requires mouse embryonic fibroblast (MEF) feeder cells to maintain the undifferenti- ated state. In order to optimize the culture conditions, human feeder cells and feeder-free, unconditioned culture systems have been developed. In vitro, hESCs can be directed to differentiate into various cell types, which lays a foundation for cell transplantation therapy and clarification of the human embryonic development. hESCs can be genetically modified in vitro, which will help to elucidate the specific genes’ regulation and functions in embryonic development. Deeper studies of hESCs will greatly further the progression of medical and life sciences, and will be finally applied in clinical medicine to benefit mankind.