Roquin-1通过Exosome调节巨噬细胞与Treg免疫应答参与肝缺血再灌注损伤的研究

Liver ischemia reperfusion （IR） injury is a complex pathophysiological process resulting in significantly impaired postoperative recovery. The liver resident macrophage (mø) and regulatory T cell (Treg) plays an important role in liver IR. Recent studies have shown the critical roles of Roquin-1 and exosome in regulating immune response. Our group found that Roquin-1 was inhibited by hepatic IR. The numbers of mø increased first and then decreased, while opposite changes were found in Treg.Roquin-1 san/san aggravated liver IR injury. Thus, we hypothesize that Roquin-1 signaling may alleviated liver IR injury by inhibiting pro-inflammatory activation of mø at the early stage, and promote hepatic recovery by enhancing regulatory function of Treg at the late stage. The exosome mediated regulation of mø/Treg by Roquin-1 may be the essencial underlying mechanism. We plan to take advantage of Roquin-1 san/san mice to study the regulation of the crosstalk between mø and Treg by Roquin-1 signaling. The underlying mechanism will be analyzed as well by in vivo IR model and in vitro mø/Treg co-culture model. Studies on how Roquin-1 regulate the crosstalk of mø/Treg will not only help to illustrate the mechanism involved in liver IR, but also provide new target and related theory basis for therapy.

肝脏缺血再灌注(IR)损伤发生机制复杂，直接影响手术预后。巨噬细胞(mø)和调节性T细胞(Treg)在肝脏IR损伤和修复中扮演了重要角色。近期研究发现，Roquin-1和外泌体介导的信号传递发挥了重要的免疫调节作用。本组研究发现，肝脏IR抑制了Roquin-1，肝内mø数量先升后降，而Treg呈现相反的变化。干扰Roquin-1的表达加重了肝脏损伤。由此，提出本假说：Roquin-1通过抑制mø的炎性反应减轻了早期损伤，并通过促进Treg的抑炎性反应加快了损伤修复。通过外泌体调控mø/Treg相互作用是Roquin-1影响肝脏IR的重要机制。本课题计划利用Roquin-1san/san小鼠，建立IR模型和体外细胞共培养模型，研究Roquin-1是否通过外泌体调控mø/Treg的相互作用，及其对肝脏IR的影响。探索肝IR中mø/Treg相互作用机制，有助于为临床干预提供新的靶点和理论依据。

Roquin-1是一种E3泛素，最初是在小鼠系统性红斑狼疮样症状的遗传因素突变筛查中发现的。已有研究证实Roquin-1有助于维持免疫稳态。巨噬细胞（macrophages，mø）中的Roquin-1通过其ROQ结构域与关键的免疫相关的mRNA相结合，并通过影响T细胞和B细胞的功能和外周稳态来调节其稳定性。我们的研究主要针对1) Roquin-1在肝脏缺血再灌注损伤中的作用2) Roquin-1对肝脏IR过程中mø极化的影响3) Roquin-1调节mø的极化和功能的分子机制。项目开展以来，我们的课题组1.成功建立相对稳定的小鼠肝脏缺血再灌注损伤模型，检测Roquin-1在肝脏IR过程中表达量的变化2.利用氯膦酸盐脂质体消除小鼠体内mø，通过尾静脉注射mø。在抑制Roquin-1的表达后，mø向M1增加，向M2减少。3.发现Roquin-1通过AMPKa/mTOR/STAT3途径调节mø极化和功能。研究Roquin-1在IR中对mø极化的调节作用及机制，为临床上减轻肝脏手术导致的缺血再灌注损伤提供新的思路及理论依据。