The role of altered immune metabolism in the inflammatory CD4+ T-cell response in equine recurrent uveitis

马复发性葡萄膜炎（ERU）是一种非常重要的疾病，它在世界范围内发生，患病率为10%，可导致失明。由于这种疾病是自发发生的，它也被证明是人类自身免疫性葡萄膜炎传播的一种模式。由于病理性免疫反应和眼睛炎症越来越被认为是许多眼部疾病的重要组成部分，以前被认为是纯粹的神经退行性疾病，因此了解这种免疫特权器官中的异常免疫反应变得越来越重要。近年来，人们已经认识到免疫细胞代谢与免疫细胞效应功能密切相关，免疫代谢在病理免疫细胞功能中的作用也越来越被研究。ERU的主要驱动因子是CD4+ T细胞。通过我们的初步工作，我们知道这些细胞的免疫代谢发生了显著改变。通过对CD4+ T细胞线粒体的差异蛋白质组学分析，我们已经证明了线粒体中负责复合体I呼吸链功能的蛋白质的选择性改变。我们还发现了与线粒体裂变和融合相关的差异丰富的蛋白质。在这个项目中，我们将分析来自对照马和患有ERU的动物血液中的活CD4+ T细胞的线粒体形态，并将其与ERU中大量迁移到眼睛的玻璃体中的CD4+ T细胞进行比较。为此，我们将使用高分辨率的STORM显微镜和3D显微镜，这将允许线粒体定位和形态的详细研究。细胞代谢对这些细胞炎症反应的影响将使用复合物I抑制剂（鱼藤酮和二甲双胍）进行研究，以了解该复合物在ERU动物CD4+ T细胞中的选择性激活。在这种复合物中，NDUFAB1在ERU动物的CD4+ T细胞中特别丰富，因此我们在这里详细描述了它的功能，以及MUL1的功能，MUL1是一种在其他模型中与异常免疫反应相关的蛋白质。除了自发患病的动物外，我们还使用了20年前用IRBP免疫过的马的生物库中的细胞，从中我们获得了诱导疾病整个过程中的PBMC。最后，我们正在研究来自ERU病例的CD4+ T细胞的代谢灵活性，以确定选择性阻断代谢途径是否可用于治疗性地影响炎症，或者细胞是否随后切换到其他营养和能量产生途径。

Equine recurrent uveitis (ERU) is a disease of great importance as it occurs worldwide with a prevalence of 10% and can lead to blindness. Because the disease occurs spontaneously, it has also been shown to be a model for the transmission of autoimmune uveitis in humans. As pathologic immune responses and inflammation of the eye are increasingly recognized as an essential component of many ocular diseases previously thought to be purely neurodegenerative, it is becoming increasingly important to understand such abnormal immune responses in this immune-privileged organ. Recently, it has become known that immune cell metabolism and immune cell effector functions are intimately linked, and the role of immune metabolism in pathological immune cell functions is increasingly being investigated. The major drivers of ERU are CD4+ T cells.Through our preliminary work, we know that the immune metabolism of these cells is significantly altered. By differential proteomic analysis of the mitochondria of CD4+ T cells, we have demonstrated selective alteration of proteins responsible for complex I respiratory chain function in mitochondria. We have also identified differentially abundant proteins associated with mitochondrial fission and fusion. In this project, we will analyze the mitochondrial morphology of live CD4+ T cells from the blood of control horses and from animals with ERU and compare them with CD4+ T cells from the vitreous that migrate in large numbers into the eye in ERU. For this purpose, we will use high-resolution STORM microscopy and 3D microscopy, which will allow detailed study of mitochondria localization and morphology. The influence of cell metabolism on the inflammatory responses of these cells will be investigated using complex I inhibitors (rotenone and metformin) to understand the selective activation of this complex in the CD4+ T cells of ERU animals. Of this complex, NDUFAB1 was particularly abundant in CD4+ T cells from ERU animals, so we characterize its function in detail here, as well as that of MUL1, a protein that has been associated with aberrant immune responses in other models. In addition to spontaneously diseased animals, we are also using cells from biobanks of horses immunized with IRBP 20 years ago, from which we have PBMC from throughout the course of induced disease. Finally, we are investigating the metabolic flexibility of CD4+ T cells from ERU cases to determine whether selective blockade of a metabolic pathway could be used to therapeutically influence inflammation or whether the cells then switch to other nutrients and energy production pathways.