IFN-γ通路相关miRNA在人早孕蜕膜NK细胞中的表达及其在不明原因复发流产发生中的作用

The natural killer cells（NK cells） in endometrial layers have been associated with the maintenance of pregnancy immunological intolerance．And the regulation roles of NK cells are reviewed in relation to maternal-fetal interface immune dysfunction in unexplained recurrent spontaneous abortions （URSA ）．The dominant lymphocytes in healthy human and murine implantation sites are pregnancy-associated uNK cells. These cells produce 90% of pregnancy induced uterine interferon γ (IFN-γ) , a cytokine that regulates cross-talk between immune cells in decidual layers. Reseachers have found that secretion of IFN-γ by mouse uterine NK cells positively regulates fetal trophoblasts and is unexpectedly associated with spontaneous abortions. However, the mechanism is still unknown..miR-146a is a miRNA that supposed to regulate innate immune, in?ammatory response and antiviral pathway negatively. In contrast, little is known regarding miR-146a function and mechanism in maternal-fetal interface immune dysfunction. To elucidate the mechanism miRNA have recently been identified as regulators that modulate target gene expression and are involved in maternal-fetal interface immune dysfunction in URSA. Our examination of the public databases predicted a number of potential targets. Prominent among these are IRAK1 (IL-1 receptor-associated kinase 1) and TRAF6 (TNF receptor-associated factor 6), which are known to be part of the common signalling pathway of IFN-γ. Regarded our previous results, we hypothesized that miR-146a was a negative regulator of the IFN pathway to induce URSA.This study is designed to investigate the contribution of miR-146a, which may be an potential pathogenesis of URSA. Transfection and stimulation of cultured cells were conducted to determine the biologic function of miR-146a. Bioinformatics prediction and validation by reporter gene assay and western blotting were performed to identify miR-146a targets.

母胎界面蜕膜NK细胞分泌过量IFN-γ是导致其微环境免疫紊乱引起临床早期不明原因反复自然流产（URSA）发生的关键因素，然而其机制不清。前期工作发现URSA患者蜕膜NK细胞miR-146a表达下降而IFN-γ分泌显著高于正常妊娠组。由于miRNA是在转录后水平通过对mRNA的靶向沉默发挥调控机制，同时生物信息学已预测出miR-146a靶基因为IFN-γ信号通路（TLR-IL-1R）中的关键基因（IRAK1、TRAF6）。因此，推测miR-146a可能作用于其靶基因，通过激活IFN-γ通路导致URSA发生。本项目拟通过扩大样本分析蜕膜NK细胞miR-146a、IFN-γ 的表达变化与早期URSA发生的相关性，进一步通过鉴定miR-146a在蜕膜NK细胞中靶基因及靶位点，从过表达及沉默miR-146a角度阐明其在IFN-γ产生中的作用机制，为早期诊断和靶向药物干预提供理论依据。

母胎界面蜕膜NK 细胞分泌过量IFN-γ 是导致其微环境免疫紊乱引起临床早期 不明原因反复自然流产（URSA）发生的关键因素，然而其机制不清。前期工作发现URSA 患者蜕膜NK 细胞miR-146a 表达下降而IFN-γ 分泌显著高于正常妊娠组。由于miRNA 是在转录后水平通过对mRNA 的靶向沉默发挥调控机制，同时生物信息学已预测出miR-146a 靶基因为IFN-γ 信号通路（TLR-IL-1R）中的关键基因（IRAK1、TRAF6）。本项目分析了蜕膜NK 细胞miR-146a、IFN-γ 的表达变化与早期URSA 发生的相关性，进一步完成了蜕膜NK 细胞miRNA表达谱及靶基因预测，探讨了URSA外周血和蜕膜NK细胞、T细胞、NKT样细胞及其1型、2型比值的多色流式细胞术检测方法，为早期诊断和靶向药物干预提供理论依据。