慢性子宫内膜炎引起的母-胎对话调节紊乱是造成奶牛繁殖障碍的主要原因。子宫内膜上皮细胞源外泌体（exosomes）及其包含miRNA在动物生殖功能发挥和胚胎早期发育等过程中具有重要作用。揭示其对胚胎滋养层细胞的影响及其机制可为全面认识母-胎对话的调控和奶牛不孕防治提供新的理论基础和依据。前期研究发现，bta-miR-218是子宫内膜炎症条件下牛子宫内膜上皮细胞来源外泌体中一个高表达的miRNA，其具体调控胚胎滋养层细胞功能的机制尚不清楚。本项目通过原位杂交、qRT-PCR、免疫荧光等方法明确bta-miR-218在子宫内膜炎奶牛子宫中表达及随外泌体在子宫内膜细胞-胚胎滋养层细胞间传递规律；通过细胞3D培养模型和基因沉默/过表达技术，进一步阐明bta-miR-218及其调节的下游靶基因影响胚胎滋养层细胞增殖、凋亡、迁移力和侵袭力的分子机制，进而从新的角度揭示子宫内膜炎影响奶牛胚胎附植的机制。

Maternal-fetal dialogue adjustment disorder caused by chronic endometritis is the main reason of causing cow reproduction obstruction. Endometrial epithelial cells derived exosomes miRNA play important roles in reproductive function of animals and early embryo development. Revealling the impact and mechanism of endometrial epithelial cells derived exosomes miRNA on trophoblast cell will provide new theoretical foundation and basis for a comprehensive understanding of maternal-fetal dialog and cows infertility prevention and control. Our previous study found that bta-miR-218 is a high expression miRNA in endometrial epithelial cell derived exosomes under endometrial inflammation conditions. However, the specific regulation mechanism of bta-miR-218 on trophoblast cell implantation function is still unknown. In this project, in situ hybridization, qRT-PCR and immunofluorescence methods were used to firstly clarify the bta-miR-218 differential expression in endometritis cows uterus and its transmission rule from endometrial epithelial cells to trophoblast cells. After that, endometrial stereoscopic/3D model and gene silence/overexpression techniques were used to further explore the molecular mechanisms of bta-miR-218 and its downstream target genes on bovine trophoblast cell proliferation, apoptosis, migration and invasion. Thus illustrating the mechanism of dairy cow embryo implantation influenced by endometritis from a new perspective.