Gerami-Naini Behzad, Dovzhenko Oksana V, Durning Maureen, Wegner Frederick H, Thomson James A, Golos Thaddeus G
Wisconsin National Primate Research Center, University of Wisconsin-Madison, 53715-1299, USA.
Endocrinology. 2004 Apr;145(4):1517-24. doi: 10.1210/en.2003-1241. Epub 2003 Dec 18.
Trophoblast differentiation and early placental development are essential for the establishment of pregnancy, yet these critical events are not readily investigated in human pregnancy. We used embryoid bodies (EBs) prepared from human embryonic stem (hES) cells as an in vitro model of early human development. The levels of human chorionic gonadotropin (hCG), progesterone, and estradiol-17beta in medium from hES cell-derived EBs grown in suspension culture for 1 wk were higher than unconditioned culture medium or medium from undifferentiated hES cells or spontaneously differentiated hES cell colonies. EBs were explanted into Matrigel (MG) "rafts" and cultured for up to 53 d. During the first 7-10 d of three-dimensional growth in MG, small protrusions appeared on the outer surface of EBs, some of which subsequently extended into multicellular outgrowths. The secretion of hCG, progesterone, and estradiol-17beta began to increase on approximately d 20 of MG culture and remained dramatically elevated over the next 30 d. EBs maintained in suspension culture failed to demonstrate this elevation in hormone secretion. Suspension-cultured and MG-embedded EBs exhibited widespread expression of cytokeratins 7/8, demonstrating extensive epithelial differentiation as well as consistent hCG expression. We propose that hES cell-derived EBs may be a useful model for investigation of human trophoblast differentiation and placental morphogenesis.
滋养层细胞分化和早期胎盘发育对于妊娠的建立至关重要，但这些关键事件在人类妊娠中难以直接进行研究。我们使用从人胚胎干细胞（hES）制备的胚状体（EBs）作为早期人类发育的体外模型。在悬浮培养1周的hES细胞来源的EBs培养基中，人绒毛膜促性腺激素（hCG）、孕酮和雌二醇-17β的水平高于未处理的培养基或未分化的hES细胞或自发分化的hES细胞集落的培养基。将EBs植入基质胶（MG）“筏”中并培养长达53天。在MG中三维生长的前7 - 10天，EBs的外表面出现小突起，其中一些随后延伸为多细胞生长物。hCG、孕酮和雌二醇-17β的分泌在MG培养约第20天开始增加，并在接下来的30天内显著升高。维持在悬浮培养中的EBs未能显示出这种激素分泌的升高。悬浮培养和MG包埋的EBs均广泛表达细胞角蛋白7/8，表明广泛的上皮分化以及持续的hCG表达。我们认为，hES细胞来源的EBs可能是研究人类滋养层细胞分化和胎盘形态发生的有用模型。
