猪原始生殖细胞生物学特性的研究

Biological Characteristics of Porcine Primordial Germ Cells

胚胎生殖细胞(embryonic germ cell,EGC)是由胎儿原始生殖细胞(primordial germ cell,PGC)经体外驯化培养获得的一种多潜能干细胞。研究猪PGC生物学特性对于建立猪EGC及了解猪生殖细胞发育机制具有重要意义。该研究以原代培养的猪PGC为对象,探讨了其生长行为特征及其重编程过程中多能性、生殖系标志基因的表达模式。结果显示,26 d胚胎生殖嵴分离的PGC呈碱性磷酸酶阳性,细胞体积及核质比较大;体外培养初期呈现出较强的增殖及迁移能力,培养第5 d细胞增殖达到平台期,此时克隆高表达Oct4、Sox2、Nanog、c-Myc、Klf4和Ifi tm3(P<0.05),低表达Blimp1(P<0.05),Nanos1和Stella的表达水平与猪胎儿成纤维细胞无差异;猪PGC形成的原代克隆已经具有多向分化潜能。

Embryonic germ cells （EGCs） are a kind of pluripotent stem cells derived from primordial germ cells （PGCs）. Studies on biological characteristics of PGCs are favorable for the establishment of EGCs and understanding the development program of germ cells. In this study, we observed growth behaviors of primary porcine PGCs as well as expression patterns of pluripotency and germline markers during their reprograrrmaing. The result showed that PGCs isolated from genital ridge of porcine embryos age of 26 d were alkaline phosphatase-positive cells, with larger size and nuclear-cytoplasmic ratio; the PGCs exhibited enhanced migration and proliferation abilities at the beginning of ex vivo cultivation, and the propagation reached a plateau at day 5, when the clones were with elevated levels of Oct4, Nanog, Sox2, c-Myc, Klf4 and Ifitm3 （P〈0.05） and depressed level of Blimp1 （P〈0.05）, compared with porcine embryonic fibroblasts. Besides, the primary clones had the potential to differentiate into different cell types.