Experimental Obstetrics and Gynecology, Medical Faculty, Otto-von-Guericke University Magdeburg, Magdeburg, Germany.
Front Immunol. 2019 Dec 10;10:2896. doi: 10.3389/fimmu.2019.02896. eCollection 2019.
Human chorionic gonadotropin (hCG) serves as one of the first signals provided by the embryo to the mother. Exactly at the time when the first step of the implantation process is initiated and the blastocyst adheres to the maternal endometrium, the embryonic tissue starts to actively secrete hCG. Shortly thereafter, the hormone can be detected in the maternal circulation where its concentration steadily increases throughout early pregnancy as it is continuously released by the forming placenta. Accumulating evidence underlines the critical function of hCG for embryo implantation and placentation. hCG not only regulates biological aspects of these early pregnancy events but also supports maternal immune cells in their function as helpers in the establishment of an adequate embryo-endometrial relationship. In view of its early presence in the maternal circulation, hCG has the potential to influence both local uterine immune cell populations as well as peripheral ones. The current review aims to summarize recent literature on the participation of innate and adaptive immune cells in embryo implantation and placentation with a specific focus on their regulation by hCG.
人绒毛膜促性腺激素（hCG）是胚胎向母体提供的第一个信号之一。就在着床过程的第一步开始，囊胚附着在母体子宫内膜上的时候，胚胎组织开始积极分泌 hCG。此后不久，这种激素就可以在母体循环中被检测到，其浓度在整个早期妊娠期间稳步增加，因为它不断地由正在形成的胎盘释放。越来越多的证据强调了 hCG 对胚胎着床和胎盘形成的关键作用。hCG 不仅调节这些早期妊娠事件的生物学方面，还支持母体免疫细胞作为建立适当胚胎-子宫内膜关系的助手的功能。鉴于其在母体循环中的早期存在，hCG 有可能影响局部子宫免疫细胞群和外周免疫细胞群。本综述旨在总结关于先天和适应性免疫细胞参与胚胎着床和胎盘形成的最新文献，并特别关注 hCG 对它们的调节作用。
