Lu X J, Deb S, Soares M J
Department of Physiology, University of Kansas Medical Center, Kansas City 66160.
Dev Biol. 1994 May;163(1):86-97. doi: 10.1006/dbio.1994.1125.
The purpose of this study was to examine part of the trophoblast cell multilineage pathway and its modulation by retinoic acid. A method for studying trophoblast cell differentiation along the spongiotrophoblast cell pathway in vitro was established and characterized. Cells were isolated from junctional zones of Day 13 rat chorioallantoic placentas via mechanical dissection, enzymatic digestion, and enrichment through a Percoll cushion. The cells were cultured up to 8 days and analyzed for their purity, morphology, and ability to express members of the placental prolactin (PRL) family. Cell preparations contained minimal mesenchymal contamination as estimated by immunocytochemical analysis for vimentin. The cells expressed PRL-like protein-A (PLP-A), PLP-B, PLP-C, and placental lactogen-I variant (PL-Iv) indicative of their differentiated spongiotrophoblast cell phenotype. Expression of members of the PRL family increased markedly during culture. Temporally the increase in PLP-A expression preceded the increased expression of PLP-B (0.9 kb), PLP-C, and PL-Iv. These in vitro observations paralleled the behavior of spongiotrophoblast cells developing in situ. Some differences were evident, including the immediate activation of PLP-B (1.2 kb) following enzymatic isolation of the cells. These cells were also susceptible to experimental manipulation. Exposure to retinoic acid influenced the morphology of the cells and the profile of members of the placental PRL family expressed by in vitro differentiated cells. In summary, a culture system has been devised to examine the control of spongiotrophoblast cell differentiation and the regulation of expression of members of the placental PRL gene family. Spongiotrophoblast cells spontaneously differentiate in vitro through discrete developmental phases that are susceptible to modulation by retinoic acid.
本研究的目的是检测滋养层细胞多谱系途径的一部分及其受视黄酸的调节作用。建立并表征了一种在体外研究沿海绵滋养层细胞途径的滋养层细胞分化的方法。通过机械解剖、酶消化以及经Percoll垫层富集，从第13天大鼠绒毛尿囊胎盘的结合区分离细胞。将细胞培养长达8天，并分析其纯度、形态以及表达胎盘催乳素（PRL）家族成员的能力。通过波形蛋白的免疫细胞化学分析估计，细胞制剂中含有极少的间充质污染。这些细胞表达催乳素样蛋白-A（PLP-A）、PLP-B、PLP-C和胎盘催乳素-I变体（PL-Iv），表明其具有分化的海绵滋养层细胞表型。在培养过程中，PRL家族成员的表达显著增加。在时间上，PLP-A表达的增加先于PLP-B（0.9 kb）、PLP-C和PL-Iv表达的增加。这些体外观察结果与原位发育的海绵滋养层细胞的行为相似。一些差异很明显，包括细胞酶解分离后PLP-B（1.2 kb）的立即激活。这些细胞也易于进行实验操作。暴露于视黄酸会影响细胞的形态以及体外分化细胞所表达的胎盘PRL家族成员的情况。总之，已设计出一种培养系统来检测海绵滋养层细胞分化的控制以及胎盘PRL基因家族成员表达的调节。海绵滋养层细胞在体外通过离散的发育阶段自发分化，这些阶段易于受到视黄酸的调节。
