The germline cells are essential for the propagation of human beings, thus essential for the survival of mankind. The germline stem cells, as a unique cell type, generate various states of germ stem cells and then differentiate into specialized cells, spermatozoa and ova, for producing offspring, while self-renew to generate more stem cells. Abnormal development of germline stem cells often causes severe diseases in humans, including infertility and cancer. Primordial germ cells (PGCs) first emerge during early embryonic development, migrate into the gentile ridge, and then join in the formation of gonads. In males, they differentiate into spermatogonial stem cells, which give rise to spermatozoa via meiosis from the onset of puberty, while in females, the female germline stem cells (FGSCs) retain stemness in the ovary and initiate meiosis to generate oocytes. Primordial germ cell-like cells (PGCLCs) can be induced in vitro from embryonic stem cells or induced pluripotent stem cells. In this review, we focus on current advances in these embryonic and adult germline stem cells, and the induced PGCLCs in humans, provide an overview of molecular mechanisms underlying the development and differentiation of the germline stem cells and outline their physiological functions, pathological implications, and clinical applications.

生殖系细胞对于人类的繁殖至关重要，因此对于人类的生存至关重要。生殖干细胞作为一种独特的细胞类型，产生各种状态的生殖干细胞，然后分化为专门的细胞，精子和卵子，用于产生后代，同时自我更新以产生更多的干细胞。种系干细胞的异常发育通常会导致人类出现严重的疾病，包括不孕症和癌症。原始生殖细胞 (PGC) 在早期胚胎发育过程中首先出现，迁移到生殖嵴，然后参与性腺的形成。在男性中，它们分化为精原干细胞，从青春期开始通过减数分裂产生精子，而在女性中，雌性生殖系干细胞 (FGSC) 在卵巢中保持干性并启动减数分裂以产生卵母细胞。原始生殖细胞样细胞 (PGCLC) 可以在体外从胚胎干细胞或诱导多能干细胞中诱导产生。在这篇综述中，我们重点关注这些胚胎和成体生殖系干细胞以及人类诱导的 PGCLC 的最新进展，概述了生殖系干细胞发育和分化的分子机制，并概述了它们的生理功能、病理学意义、和临床应用。