Establishment of bovine trophoblastic cell lines

本研究的目的是从体外受精的胚胎细胞中培养出滋养层细胞系，为分析牛着床和胎盘形成的机制奠定基础。在探索这些机制时，滋养层细胞系可以提供大量信息。不幸的是，由于很难长期培养连续的细胞群，牛身上几乎没有用于这一目的的细胞系。本研究用骨形态发生蛋白4(BMP4)建立了12个新的细胞系。这些细胞系传代约30代，它们保留了滋养细胞的特征，并表达牛滋养细胞基因：胎盘催乳素、干扰素-τ、妊娠相关糖蛋白1和催乳素相关蛋白1。尽管不同细胞系的基因表达模式不同，且取决于细胞，但至少有四个特征。表达牛POU结构域5类转录因子1和尾型Homebox 2。定量RT-PCR和免疫组织化学检测证实了这些基因的表达。这些结果表明，BMP4参与了从早期胚胎细胞向滋养层细胞系的培养，新开发的细胞系可以为不同类型的牛滋养层细胞提供不同的细胞系。这可能成为检查滋养细胞分化的一个重要的新工具。

The purpose of this study is to raise the trophoblastic cell lines from in vitro fertilized embryonic cells for analyzing the mechanism of bovine implantation and placentogenesis. In exploring these mechanisms, trophoblastic cell lines can provide substantial information. Unfortunately, there are few cell lines for this purpose in cattle because of the difficulty of raising successive cell stock in the long term. In this study, 12 new cell lines were established using bone morphogenetic protein 4 (BMP4). These cell lines were maintained for around 30 passages, and they retained trophoblastic characteristics and expressed bovine trophoblastic genes: placental lactogen, interferon-τ, pregnancy-associated glycoprotein 1, and prolactin-related protein 1. Although the gene expression patterns were different among cell lines and depended on the cells, there were at least four characteristics. All of them expressed bovine POU domain class 5 transcription factor 1 and caudal-type home box 2. The expression of these genes was confirmed by quantitative RT-PCR and immunohistochemical detection. These results suggest that BMP4 is involved in the raising of trophoblast cell lines from early embryonic cells and the newly developed cell lines can provide different types of bovine trophoblastic cells with different cell lineages. This may constitute a significant new tool for the examination of trophoblastic differentiation.