Role of mitochondria in SLE and its cardiovascular complications

摘要：细胞死亡后，细胞释放受损的线粒体，导致局部 发炎。本研究的总体目标是研究线粒体是如何 清除以避免引起异常免疫反应，并确定自身抗体 靶向线粒体蛋白在评估血栓形成进展中的临床价值 系统性红斑狼疮(SLE)患者。研究的前提是系统性红斑狼疮患者 损害线粒体的清除，促进线粒体抗体的发展， 炎症和器官损伤，包括血栓形成。为了调查这一点，我们主要有三个方面 目标。第一个目标是研究线粒体挤出如何促进自身免疫 线粒体蛋白抗原，试图确定新的主要线粒体的确切靶点 自身抗体，AMA-17，在体外暴露自身抗原的过程，以及 潜在的治疗靶点，例如线粒体ROS，参与在体内产生AMA-17。 第二个目的是研究抗线粒体抗体如何参与血栓形成。 发展。使用一个大型纵向系统性红斑狼疮队列(n=500)，跟踪超过10年，我们将 测定AMA-17与静脉发育相关和/或预测静脉发育的能力 血栓形成。亲和纯化的AMA-17抗体将用于检测血小板活化和 体外血栓形成的流式细胞术、聚集率测定和尖端模型 利用一种新的抗体介导的静脉模型进行微血管工程和体内实验 血栓形成是奈特博士开发的。最后，在目标3中，我们将调查潜在的 线粒体清除的机制，重点是补体的作用 C1q和C3，以方便无声通关。这些研究将在体外使用SELECT 分离补体成分，以及在体内使用独特的C1q和C3缺陷小鼠。 结果测量包括吞噬、细胞因子产生和净形成。 参与线粒体介导的炎症的下游信号通路将是 使用基于质谱学的磷酸蛋白质组学进行鉴定。总而言之，我们的研究旨在 确定炎症、血栓形成和自身免疫的基本调控机制 人类疾病的背景，强调补体系统在沉默中的作用 去除线粒体。我们期望拟议的研究能提供新的治疗靶点。 破坏线粒体的炎症和免疫原性，适用于许多 疾病，包括系统性红斑狼疮和类风湿性关节炎，以及识别预后线粒体- 衍生生物标志物使静脉血栓的早期和预防性治疗成为可能。

Summary: Upon cellular death, cells release damaged mitochondria, contributing to local inflammation. The overall aims of the present study are to investigate how mitochondria are cleared to avoid evoking an aberrant immune response, and to determine if autoantibodies targeting mitochondrial proteins have clinical utility in assessing development of thrombosis in patients with systemic lupus erythematosus (SLE). The premise of the study is that SLE patients have impaired clearance of mitochondria, promoting development of mitochondrial antibodies, inflammation and organ damage, including thrombosis. To investigate this we have three main aims. The first aim investigates how mitochondrial extrusion promotes autoimmunity towards mitochondrial protein antigens, attempting to define the exact target of novel main mitochondrial autoantibody, AMA-17, the processes involved in exposing the autoantigen in vitro, as well as potential therapeutic targets, e.g. mitochondrial ROS, involved in generating AMA-17 in vivo. The second aim investigates how anti-mitochondrial antibodies partake in thrombosis development. Using a large longitudinal SLE cohort (n=500), followed over 10 years, we will determine the capacity of AMA-17 to associate with and/or predict development of venous thrombosis. Affinity-purified AMA-17 antibodies will be tested for platelet activation and thrombus formation in vitro using flow cytometry, aggregometry and a cutting-edge model of engineered microvessels, as well as in vivo using a novel model of antibody-mediated venous thrombosis developed by Dr. Knight. Finally, in Aim 3, we will investigate underlying mechanisms involved in clearance of mitochondria, with an emphasis on the role of complement C1q and C3 to facilitate silent clearance. These studies will be done both in vitro using select isolated complement components, as well as in vivo using unique C1q and C3 deficient mice. Outcome measures include phagocytosis, cytokine production, and NET formation. Downstream signaling pathways involved in mitochondrial-mediated inflammation will be identified using mass spectrometry-based phosphoproteomics. In all, our study aims at identifying fundamental mechanisms regulating inflammation, thrombosis and autoimmunity in the context of human disease, with an emphasis on the role of the complement system in silent removal of mitochondria. We expect the proposed research to provide novel therapeutic targets disrupting the inflammatory and immunogenic properties of mitochondria, applicable for many diseases, including SLE and rheumatoid arthritis, as well as identify prognostic mitochondrial- derived biomarkers enabling early and preventive treatment of venous thrombosis.