血液中的小胞外囊泡在急性脑缺血后炎症应答中作用和机制的系统生物学研究

炎症应答在脑缺血后的组织损伤修复中发挥重要作用，是开发卒中新疗法的关键靶标。小胞外囊泡(sEV)是细胞间信息传递的新途径，参与炎症在内的多种生物学过程。前期研究发现卒中患者血清sEV中脑特异及炎症相关miRNA含量增加，我们推测：随血脑屏障破坏，脑内sEV释放入血，血液sEV也可进入受损部位并参与炎症应答。sEV成分复杂且功能多样，本研究将利用患者血清样本结合小鼠MCAO模型，通过系统生物学方法从4个方面验证该假说：①通过测序和蛋白质组学检测脑缺血对血液sEV中RNA和蛋白成分的影响；②构建Flag标签sEV追踪血液sEV在缺血脑组织中的时空分布；③通过体内外实验解析血液sEV在脑缺血后炎症应答中的作用及可能的细胞分子机制；④构建工程化sEV, 探讨改变sEV成分调控脑缺血后炎症应答、减轻损伤促进修复的可能。本研究将加深对脑缺血后炎症应答机制的认识，为减轻脑缺血损伤提供新的思路和实验基础。

Post-stroke inflammation plays essential roles in tissue damage and repair after cerebral ischemia, and is a primary target for the development of new therapies for stroke. Small EV, a new way of intercellular communication, is involved in multiple biological processes, including inflammation. Our previous studies found the increased brain-specific and inflammation-related miRNA in serum sEV from stroke patients. We speculated that with the destruction of the blood-brain barrier, intracerebral sEV was released into the blood, and blood sEV could also enter the damaged site and participate in the inflammatory response. Due to the complexity of sEV components and functions，in this study, by using the serum samples of stroke patients and the MCAO mice model, the hypothesis will be tested from four aspects through systematic biology. 1. To reveal the effects of cerebral ischemia on the expression profiles of blood sEV RNA and protein through second-generation sequencing and quantitative proteomics; 2. To track the spatial and temporal distribution of blood sEV in ischemic brain tissue by a Flag-labeled sEV; 3. To analyze the roles of blood sEV in post-stroke inflammation and the possible underlying cellular and molecular mechanisms by in vivo and in vitro experiments. 4. To construct engineered sEV and explore the possibility of regulating the post-stroke inflammation, reducing the damage, and promoting repair by modifying the components of sEV. This study will deepen our understanding of the mechanism underlying the post-stroke inflammatory response and provide new ideas and experimental basis for the alleviation of cerebral ischemia injury.