The Role of Myeloid Cell-Specific Ten-Eleven Translocase 2 (TET2) in Regulation of Neuroinflammation

骨髓细胞特异性 10-11 转位酶 2 (TET2) 在神经炎症调节中的作用

• 批准号: 10228836
• 负责人: Ashley Munie Gardner
• 金额: $ 3.82万
• 依托单位: UNIVERSITY OF MICHIGAN AT ANN ARBOR
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-04-01 至 2023-09-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10228836
• 关键词: Address; Adoptive Transfer; Aggressive Clinical Course; Animal Model; Anti-Inflammatory Agents; Antigen Presentation; Autoimmune; Blocking Antibodies; Blood; Bone Marrow; CD4 Positive T Lymphocytes; CD86 gene; CNS autoimmune disease; CNS autoimmunity; Cell physiology; Cells; Cellular Infiltration; ChIP-seq; Clinical; Cytokine Activation; Cytosine; DNA; Data; Demyelinations; Development; Dioxygenases; Disease; Down-Regulation; Enterobacteria phage P1 Cre recombinase; Enzymes; Epigenetic Process; Etiology; Experimental Autoimmune Encephalomyelitis; Family; Flow Cytometry; Fluorescence-Activated Cell Sorting; Frequencies; Gene Expression; Genetic; Genetic Predisposition to Disease; Genetic Transcription; Goals; Immunohistochemistry; In Vitro; Inflammation; Inflammatory; Interleukin-1 beta; Interleukin-4; Interleukin-6; Knock-out; Laboratories; Lead; Malignant Neoplasms; Measures; Mediating; Methylation; Microarray Analysis; Modification; Multiple Sclerosis; Multiple Sclerosis Lesions; Mus; Myelin; Myelogenous; Myeloid Cell Activation; Myeloid Cells; Nervous System Trauma; Neuraxis; Nucleic Acid Regulatory Sequences; Outcome; PTPRC gene; Pathogenesis; Pathologic; Pathology; Pathway interactions; Patients; Peripheral Blood Mononuclear Cell; Phagocytosis; Phenotype; Play; Population; Production; Property; Regulation; Reporter; Research; Role; Severities; Spleen; Susceptibility Gene; System; Tamoxifen; Time; Transcript; Transgenic Mice; alpha ketoglutarate; central nervous system demyelinating disorder; chemokine; conditional knockout; cytokine; demethylation; disability; experience; genetic risk factor; interest; loss of function mutation; member; mouse model; multiple sclerosis patient; multiple sclerosis treatment; neuroimmunology; neuroinflammation; neuropathology; neurotoxicity; new therapeutic target; novel; oxidation; programmed cell death ligand 1; promoter; single-cell RNA sequencing; therapeutic target; translocase

PROJECT SUMMARY Multiple sclerosis (MS) is an inflammatory demyelinating disease of the central nervous system (CNS) believed to be autoimmune in etiology. Analysis of MS lesions, as well as studies in experimental autoimmune encephalomyelitis (EAE), a murine model of MS, have indicated that myeloid cells are likely a critical component of the pathogenesis of CNS autoimmunity. Recently, Ten-Eleven Translocase 2 (TET2) was identified as a genetic susceptibility locus for MS. TET2 is a Fe(III)-, α-ketoglutarate-dependent enzyme that catalyzes the oxidation of methylated cytosine to 5’-hydroxymethyl cytosine (5hmC) and promotes active demethylation. 5hmC is a stable epigenetic mark that can either activate or repress gene expression in a cell- and loci-dependent manner. There is growing evidence that TET2 acts as a negative regulator of myeloid cell activation and function, promoting a homeostatic or anti-inflammatory cell state. My hypothesis is that TET2 restrains the pro- inflammatory functions of myeloid cells to limit inflammation, neurological damage, and disability during CNS autoimmunity. Supporting this hypothesis, TET2 and 5hmC were found to be reduced in peripheral blood mononuclear cells of MS patients when compared with controls. Preliminary data from our laboratory demonstrates that the reduction of TET2 and 5hmC in peripheral blood mononuclear cells is recapitulated in EAE, and that TET2 transcripts and 5hmC content are further reduced in CNS-infiltrating myeloid cells compared with the periphery. Additionally, adoptive transfer of encephalitogenic Th17 cells into Tet2+/- mice led to an exacerbated clinical course compared with Tet2+/+ mice. To continue addressing my hypothesis, I will first examine the impact of TET2 deficiency in myeloid cells on clinical and pathological outcomes of EAE (Aim 1). I will do this by examining the EAE disease course, pathology, and cellular infiltration in mice where Tet2 is knocked out specifically in myeloid cells using a Cre/lox genetic system. Additionally, I will identify the targets of TET2 in CNS-infiltrating myeloid cells, such as the suppression of pro-inflammatory cytokine production and the conversion of myeloid cells from a pro-inflammatory phenotype to an anti-inflammatory phenotype (Aim 2). Completion of these aims will contribute to the fields of neuroimmunology and epigenetics by exploring a novel mechanism of myeloid cell regulation during CNS autoimmunity, and may lead to the discovery of novel myeloid cell-specific therapeutic targets for the treatment of MS and related disorders.

项目概要 多发性硬化症 (MS) 是一种中枢神经系统 (CNS) 炎症性脱髓鞘疾病 从病因学上看是自身免疫性的。 MS 病变分析以及实验性自身免疫研究 脑脊髓炎 (EAE) 是 MS 的一种小鼠模型，表明骨髓细胞可能是 MS 的关键组成部分 中枢神经系统自身免疫的发病机制。最近，10-11 易位酶 2 (TET2) 被确定为 MS 的遗传易感性位点。 TET2 是一种 Fe(III)-、α-酮戊二酸依赖性酶，可催化 甲基化胞嘧啶氧化为 5'-羟甲基胞嘧啶 (5hmC) 并促进主动去甲基化。 5hmC 是一种稳定的表观遗传标记，可以激活或抑制细胞和基因座依赖性的基因表达 方式。越来越多的证据表明 TET2 作为骨髓细胞激活和功能的负调节因子， 促进体内平衡或抗炎细胞状态。我的假设是 TET2 抑制亲 骨髓细胞的炎症功能，以限制中枢神经系统期间的炎症、神经损伤和残疾 自身免疫。外周血中 TET2 和 5hmC 的减少支持了这一假设 与对照组相比，多发性硬化症患者的单核细胞。我们实验室的初步数据 证明外周血单核细胞中 TET2 和 5hmC 的减少重现于 EAE，并且与 CNS 浸润性骨髓细胞相比，TET2 转录本和 5hmC 含量进一步减少 与外围。此外，将致脑炎 Th17 细胞过继转移至 Tet2+/- 小鼠中导致 与 Tet2+/+ 小鼠相比，临床病程加剧。为了继续解决我的假设，我首先 检查骨髓细胞 TET2 缺乏对 EAE 临床和病理结果的影响（目标 1）。我 将通过检查 Tet2 所在小鼠的 EAE 病程、病理学和细胞浸润来做到这一点 使用 Cre/lox 遗传系统在骨髓细胞中特异性敲除。此外，我将确定以下目标： CNS 浸润性骨髓细胞中的 TET2，例如抑制促炎细胞因子的产生和 骨髓细胞从促炎表型转变为抗炎表型（目标 2）。 完成这些目标将通过探索一种新颖的方法为神经免疫学和表观遗传学领域做出贡献 中枢神经系统自身免疫过程中骨髓细胞调节机制，并可能导致新骨髓细胞的发现 用于治疗多发性硬化症和相关疾病的细胞特异性治疗靶点。