Metabolic regulators of Treg/Th17 balance in CNS autoimmunity

项目总结/摘要 自身免疫组织炎症由效应T细胞和调节T细胞之间的平衡决定。 在自身免疫反应中，效应T细胞过度增殖，产生促炎细胞因子 并抑制导致炎症的调节性T细胞的扩增和产生。细胞因子发挥作用 在这一过程中起着关键作用，但其他因素，如新陈代谢和身体因素，如氧张力， 组织微环境中的pH和空间在调节效应子与Treg中起着同样重要的作用 平衡然而，组织中的T细胞代谢的分析是具有挑战性的，这是由于技术的局限性。 可用的细胞数量和当前的代谢技术。我们开发了一种新的计算 该算法称为Compass，可以使用单细胞RNAseq数据预测细胞的代谢状态。 通过这个工具，我们确定多胺代谢是Th17致病性的主要驱动力 细胞在此，我们观察到Odc1抑制可以通过增加线粒体功能来调节线粒体功能。 线粒体复合体稳定性基因与效应T细胞功能的潜在后果。此外，本发明还 我们的初步数据表明多胺途径（限速酶， Odc1）和表观基因组修饰物JMJD3/Kdm6b。我们还提供了证据， Odc1-JMJD3轴通过化学抑制剂或基因缺失修饰转录组和表观基因组 Th17细胞（基因组可及性）有利于TcB，与CNS中的组织炎症相关， 实验性自身免疫性脑脊髓炎（EAE）。根据这些数据，我们假设， 多胺途径是效应子与Treg分化的关键代谢和表观遗传调节因子 从而影响组织炎症的发展。该通路的关键元件Odc1- JMJD3轴是一个受细胞因子调控的检查点，可以感知环境信号， 并随后调节T细胞的代谢和表观基因组状态， 调节效应细胞与调节性T细胞的平衡。我们将从两个方面来检验这一假设：1）确定 多胺生物合成如何限制线粒体oxphos和促进反向电子传递， 在EAE期间发炎CNS中冲击效应物与Treg发育; 2）确定多胺是否 代谢酶Odc1干扰JMJD3功能以调节T细胞的基因组可及性 在EAE发展过程中，Th17细胞的发育优于Treg细胞。多胺代谢 这可能在T细胞生物学中具有更广泛的意义。因此，我们将重点讨论 Th17/Treg平衡背景下炎症CNS中的Odc1-JMJD3轴这项研究建议高度 与人类疾病有关，反映在多种疾病之间的重大重叠（约25%）- 硬化风险变体和差异调节效应子Th17与Treg分化的基因。

PROJECT SUMMARY/ ABSTRACT Autoimmune tissue inflammation is dictated by a balance between effector and regulatory T cells. During an autoimmune reaction, effector T cells hyper proliferate, produce pro-inflammatory cytokines and suppress expansion and generation of regulatory T cells resulting in inflammation. Cytokines play a key role in the process, but other factors such as metabolism and physical factors like oxygen tension, pH and space in tissue microenvironment play an equally important role in regulating effector vs. Treg balance. However, the analysis of T cell metabolism in tissue is challenging due to limitations of available cell numbers and current metabolic techniques. We developed a novel computational algorithm called Compass that can predict metabolic state of cells using single cell RNAseq data. Facilitated by this tool, we identified polyamine metabolism as a major driver of pathogenicity of Th17 cells. Herein we observed that Odc1 inhibition can regulate mitochondrial function by increasing mitochondrial complex stability genes with potential consequences in effector T cell function. Further, our preliminary data suggests a connection between the polyamine pathway (rate limiting enzyme, Odc1) and an epigenome modifier, JMJD3/Kdm6b. We also provide evidence that inhibition of the Odc1-JMJD3 axis by chemical inhibitors or genetic deletion modifies the transcriptome and epigenome (genome accessibility) of Th17 cells in favor of Tregs with relevance in tissue inflammation in CNS in experimental autoimmune encephalomyelitis (EAE). Based on these data we hypothesize that polyamine pathway is a critical metabolic and epigenetic regulator of effector vs. Treg differentiation and thereby affects development of tissue inflammation. The key element of the pathway, Odc1- JMJD3 axis is a checkpoint that can be regulated by cytokines and can sense environmental cues such as hypoxia and subsequently adjust metabolic and epigenomic state of T cells to regulate effector vs. regulatory T cell balance. We will test this hypothesis in two aims: 1) determine how polyamine biosynthesis restricts mitochondrial oxphos and promotes reverse electron transport to impact effector vs. Treg development in inflamed CNS during EAE; 2) determine whether polyamine metabolism enzyme Odc1 interferes with JMJD3 function to modulate the genome accessibility of T cells favoring Th17 over Treg development during EAE development. The polyamine metabolism pathway likely has broader implications in T cell biology. Hence, we will focus on the relevance of the Odc1-JMJD3 axis in inflamed CNS in the context of Th17/Treg balance. The proposed study is highly relevant in human diseases as reflected by a significant overlap (about 25%) between multiple- sclerosis risk variants and genes that differentially regulate effector Th17 vs. Treg differentiation.