Cellular and Molecular Aspects of Implantation

描述（由申请方提供）：着床后蜕膜的形成被认为是胚胎免受母体伤害的保护屏障。因此，着床缺陷和子宫蜕膜化可能是早期妊娠丢失的原因。胚胎细胞类型和胚胎因子的识别，以植入和蜕膜化将是一个重大成就，以提高生育力。紧密连接（TJ），创建一个限制细胞旁渗透性的屏障，只存在于上皮细胞，但不存在于基质中。 我们首次注意到，在妊娠第6天，围绕植入囊胚的初级蜕膜区（PDZ）的基质细胞表达TJ及其相关蛋白，闭合蛋白，claudin-1，闭合小带-1（ZO-1）和ZO-2，而次级蜕膜区（SDZ）的基质细胞不表达TJ及其相关蛋白。我们的初步研究结果表明，滋养层（Tr），而不是内细胞团（ICM），胚泡诱导植入和蜕膜化反应与正确表达ZO-1的PDZ。我们还提供了证据表明，肝素结合表皮生长因子样生长因子（HB-EGF）的胚泡是重要的植入，蜕膜化，ZO-1在PDZ的表达。这些观察结果与静脉内给药后正常囊胚诱导的大分子染料通过PDZ的限制一起，而不是通过人工诱导的蜕膜化，表明胚胎HB-EGF影响植入，PDZ形成和PDZ中TJ的发生，其产生无血管通透性屏障以保护胚胎。因此，我们的具体目标是在小鼠模型中确定：1）Tr在植入和PDZ形成中的影响，2）胚胎HB-EGF在植入和PDZ形成中的影响，3）HB-EGF在基质细胞向具有上皮特征的蜕膜细胞转化中的影响，以及4）PDZ作为母胎界面屏障的重要性。我们将使用多种实验方法，包括RT-PCR，北方和原位杂交，免疫组织化学/免疫荧光，Western印迹，磷酸化，电子显微镜，胚胎培养和转移，细胞培养，体内/体外腺病毒载体驱动的基因传递，以及其他来实现我们的目标。这些结果将进一步加深我们对子宫保护机制的理解，以保护早期妊娠期间的植入胚胎。

DESCRIPTION (provided by applicant): The formation of deciduum following implantation is considered to function as a protective barrier to the embryo from the maternal insults. Thus, defective implantation and uterine decidualization may account for early pregnancy losses. Identification of embryonic cell-type(s) and embryonic factor(s) for implantation and decidualization will be a major achievement to improve fecundity. The tight junction (TJ) that creates a barrier restricting the paracellular permeability is present only in cells of the epithelium, but not in the stroma. We noticed for the first time that the stromal cells of the primary decidual zone (PDZ) surrounding the implanting blastocyst, but not the secondary decidual zone (SDZ), on day 6 of pregnancy express the TJ and its associated proteins, occludin, claudin-1, and zonula occludens-1 (ZO-1) and ZO-2. Our preliminary results show that the trophoblast (Tr), but not the inner cell mass (ICM), of the blastocyst induces implantation and decidualization reactions with correct expression of ZO-1 in the PDZ. We also provide evidence here that heparin binding-epidermal growth factor-like growth factor (HB-EGF) produced by the blastocyst is important for implantation, decidualization, and ZO-1 expression in the PDZ. These observations together with the restriction of passage of macromolecular dye to the PDZ induced by normal blastocysts after intravenous administration, but not by artificially induced decidualization, suggest that the embryonic HB-EGF influences implantation, the PDZ formation, and genesis of the TJ in the PDZ which creates an avascular permeability barrier to protect the embryo. Therefore, our specific aims are to determine in a murine model: 1) Influence of the Tr in implantation and the PDZ formation, 2) Influence of embryonic HB-EGF in implantation and the PDZ formation, 3) Influence of HB-EGF in the transformation of stromal cells to decidual cells with epithelial characteristics, and 4) The importance of the PDZ as a barrier at the maternal-fetal interface. We will use multiple experimental approaches including RT-PCR, Northern and in situ hybridizations, immunohistochemistry/ immunofluorescence, Western blotting, phosphorylation, electron microscopy, embryo culture and transfer, cell culture, in vivo/in vitro adenoviral vector-driven gene delivery, and others to accomplish our goals. These results will further our understanding regarding uterine protective mechanism(s) to the safeguard of the implanting embryo during early pregnancy.