Embryonic stem cells (ESC) are pluripotent cells derived from the inner cell mass (ICM) of pre-implantation mouse embryos or primordial germ cells (PGC) of embryos, and are capable of both self-renewal and multilineage differentiation.

• 胚胎干细胞(embryonic stem cells，ESC)是从囊胚期的内细胞团(inner cell mass，ICM)和早期胚胎的原始生殖细胞(primordial germ cell，PGCs)中分离到一类具有自我更新能力的多潜能性细胞。 自胚胎干细胞建系成功以来，人们对干细胞的生物学特性(如：具有自我更新能力及多向分化潜能)有了深入的了解。