子宫内膜容受期宫腔液外泌体miRNA在胚胎着床中的作用及调控机制初探

As a liquid microenvironment, uterine luminal fluid(ULF) contains nano-packages called exosomes, which mediate the intercellular communication and harmonize maternal-fetus conversation to facilitate the embryo implantation. miRNAs which are proved to play an important role in embryo implantation are differentially enrich in the exosomes and potentially participate the maternal-fetus negotiation. During the endometrial receptive period, the endometria secrets exosomes, which are specifically packaged with miRNAs, into the uterine cavity fluid and regulate embryo implantation. To elucidate uterine cavity fluid exosome-miRNAs who paly important role in the implantation and uncover the mysterious mechanism, we are planning to use high-throughput sequencing to reveal the differential expression of exosome-miRNAs profile by comparing the receptive and non-receptive uterine cavity fluid derived exosomes and select the miRNA which are predicted to participate in embryo implantation signaling pathways. By using gene transfection technology, we will verify the miRNA which truly regulate embryo implantation and detail its mechanism. Result of our project will provide a great progress to the development of non-invasive endometrial receptivity biomarkers and help to guide individual embryo transfer in clinical implementation.

子宫宫腔液作为胚胎着床的微环境，内含的外泌体可以通过介导细胞间通迅，协调母胎对话，参与调节胚胎着床。miRNA是外泌体的分子内容物，也是胚胎着床的重要调控分子。在子宫内膜容受期，子宫内膜细胞选择性的将关键miRNAs包装至外泌体，并将其释放到宫腔液中，调控胚胎着床。为寻找人类子宫内膜容受期宫腔液外泌体中与胚胎植入相关的关键miRNAs，并初步探索其在胚胎着床中的作用及调控机制，我们拟采用高通量技术对人类子宫内膜容受期及非容受期宫腔液的外泌体miRNAs进行测序分析，构建差异表达谱，筛选并验证与胚胎植入信号通路相关的关键miRNAs，再用基因转染技术从功能上再次筛选关键miRNAs，得到目的miRNAs并探究其在胚胎着床中的作用及调控机制，为未来开发无创子宫内膜容受性生物标志物及临床实施个体化胚胎移植奠定基础。

子宫宫腔液（uterine fluid）作为胚胎着床的微环境，内含的外泌体（extracellular vesicle，EV）可以通过介导细胞间通迅，协调母胎对话，参与调节胚胎着床。miRNA是EVs的分子内容物，也是胚胎着床的重要调控分子。在子宫内膜容受期，子宫内膜细胞选择性的将关键miRNAs包装至EVs，并将其释放到宫腔液或者胚胎，调控胚胎着床。本研究通过收集首次IVF即妊娠的女性患者的容受前期与容受期的UF EVs，建立了容受期UF EVs miRNA表达谱，筛选并验证了差异表达基因从而得到了关键基因miR-223-3p。通过滋养细胞对宫腔液及内膜上皮细胞来源的EVs的摄取以及细胞运动能力研究，证明了滋养细胞可以摄入EVs并与浓度及孵育时间呈正相关，且EVs增强了滋养细胞的迁移、侵袭及黏附能力。通过对滋养细胞进行miR-223-3p的上调/下调转染，我们发现miR-223-3p上调表达会明显促进滋养细胞的着床能力。miR-223-3p下调表达的滋养细胞着床能力下降，与容受期UF EVs共培养后，其着床能力有所上升。通过在线数据库对miR-223-3p靶标基因预测，TP53、FOXO1和FOXO3可能是其调控胚胎着床的靶基因。该研究表明宫腔液及内膜上皮细胞外泌体促进胚胎着床，容受期宫腔液外泌体可以通过输送miR-223-3p至滋养细胞调控胚胎着床，为未来开发无创子宫内膜容受性生物标志物及改善患者内膜容受性提供了实验基础。