血清外泌体miRNA-766-3p促进巨噬细胞异常活化参与狼疮性肾炎发生发展的机制研究

Exosomes are crucial in the development of systemic lupus erythematosus (SLE).In the preliminary experiments,we discovered that serum exosomes in lupus nephritis (LN) patients promoted the infiltration of renal macrophages and the development of LN in mice.The low expression of miR-766-3p in LN exosomes could regulate Akt expression. Based on these findings,we hypothesize that the low expression of miR-766-3p in exosomes could regulate PI3K/Akt/mTOR signaling,inhibit autophagy,lead to NLRP3 inflammasome activation, promote macrophage infiltration in the kidney and finally result in LN. To test our hypothesis,we will use transgenic mice, gene interference and inhibitor treatmenttechniques to clarify the effect of serum exosomes on macrophage activation and the developmentof LN. We will analyze the effect of miR-766-3p on the regulation of PI3K/Akt/mTOR signaling.Then test whether miR-766-3p regulates autophagy and NLRP3 inflammasome activation. Finally, we will observe the effects of miR-766-3p and NLRP3 inflammasome activation on LN in SLE model mice. Results from this project will help us to understand the mechanism of LN and provide basis for better diagnosis and treatments of LN.

外泌体（exosomes）在SLE发生发展中至关重要。课题组发现LN患者血清外泌体移植促进小鼠肾脏巨噬细胞浸润及LN的发生，且LN患者外泌体中低表达的miR-766-3p可调节Akt表达。据此提出假说：外泌体中低表达miR-766-3p调节PI3K/Akt/mTOR信号转导，抑制自噬，促进NLRP3炎症小体激活，导致巨噬细胞活化及LN发生。本项目拟在SLE动物模型、巨噬细胞中，利用转基因小鼠，使用基因干扰、抑制剂处理等技术，首先明确LN患者来源的外泌体对LN发生及巨噬细胞激活的影响并分析miR-766-3p的作用，阐明miR-766-3p对PI3K/Akt/mTOR信号转导的调节机制，并明确miR-766-3p调节细胞自噬与NLRP3炎症小体激活关系。最后观察干预miR-766-3p及NLRP3炎症小体激活对SLE小鼠LN发生的影响。研究结果为阐明LN的发生机制及寻找治疗方法提供理论依据。

系统性红斑狼疮（SLE）是一种累及全身多系统的自身免疫性疾病，狼疮性肾炎（LN）是其最严重的并发症之一，Exosomes是细胞间通讯的重要工具，研究表明，exosomes的异常参与SLE发生发展过程。本项目组首先分离SLE不伴LN患者及伴LN患者血清的exosomes，并鉴定成功，且LN患者血清的exosomes可促进MRL/lpr鼠肾炎的疾病进展及巨噬细胞活化；接着大样本验证miR-766-3p在伴有LN患者血清exosomes中低表达，有多条信号通路富集，并且miR-766-3p与患者病史、白蛋白、IgA呈正相关，与肾炎呈负相关，与SLEDAI评分、自身抗体、用药等无相关性。在此基础上项目组也探讨miR-766-3p调节巨噬细胞激活与细胞自噬及NLRP3炎症小体之间关系，初步探讨可exosomes中miR-766-3p对LN的影响。我们发现SLE不伴LN和伴LN患者血清exosomes中miRNA存在差异，伴LN患者exosomes中miR-766-3p低表达，可通过PI3K/Akt/mTOR信号通路导致巨噬细胞自噬减少，NLRP3炎症小体增多，促进巨噬细胞活化，进而导致LN的发生发展。本研究将进一步阐明LN的发病机制，寻找新的LN新的治疗靶点，对于丰富LN的发病机制及寻找新的治疗方案具有极为重要的意义。项目经费按照预算计划使用，共发表论文14篇，共培养研究生3名。