The Role of APOE Signaling in Microglia in Glaucoma

APOE 信号传导在青光眼小胶质细胞中的作用

• 批准号: 10238886
• 负责人: Milica Margeta
• 金额: $ 23.43万
• 依托单位: MASSACHUSETTS EYE AND EAR INFIRMARY
• 依托单位国家: 美国
• 财政年份: 2019
• 资助国家: 美国
• 起止时间: 2019-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10238886
• 关键词: Ablation; Address; Age related macular degeneration; Alleles; Alzheimer' s Disease; Alzheimer' s disease model; Amyotrophic Lateral Sclerosis; Animals; Apolipoprotein E; Apoptotic; Area; Behavioral; Biological Response Modifiers; Biology; Brain; Cell Differentiation process; Cell Survival; Cells; Chronic; Clinical; Data; Development; Disease; Electroretinography; Endothelin-1; Exhibits; Eye; Genes; Glaucoma; Goals; Human; Immune; Knowledge; Laboratories; Late Onset Alzheimer Disease; Link; Lipoproteins; Literature; LoxP-flanked allele; Microglia; Microspheres; Modeling; Molecular Profiling; Monoclonal Antibodies; Multiple Sclerosis; Mus; Myeloid Cells; Nerve Degeneration; Nervous system structure; Neurodegenerative Disorders; Neurons; Optic Nerve; Pathogenesis; Peripheral; Personal Communication; Phagocytosis; Phenotype; Physiologic Intraocular Pressure; Play; Population; Production; Program Development; Protein Isoforms; Publishing; Research; Retina; Retinal Ganglion Cells; Risk Factors; Role; Scientist; Signal Transduction; Tamoxifen; Testing; Training Programs; Variant; Visual Fields; Visual evoked cortical potential; apolipoprotein E-2; apolipoprotein E-4; career; cell injury; cell type; common treatment; cytokine; macrophage; modifiable risk; monocyte; mouse model; neurodegenerative phenotype; neuroinflammation; neuroprotection; neurotoxic; novel; optic cup; recruit; response; retinal ganglion cell degeneration; transcriptome sequencing

This proposal describes a 3-year training program for the development of an academic career focused on understanding the role of retinal neuroinflammation in glaucoma. My research goal is to elucidate the role of microglia, resident immune cells in the retina and the brain, in the pathogenesis of glaucoma. Our preliminary data demonstrate that in the microbead glaucoma model, microglia suppress homeostatic genes and induce a disease-associated molecular signature (MGnD), which is shared with brain neurodegenerative diseases. In addition to the induction of proinflammatory cytokines and neurotoxic substances, MGnD microglia also significantly upregulate production of APOE, the major lipoprotein in the brain. APOE has recently been found to critically regulate MGnD molecular signature in brain microglia, and is genetically linked to Alzheimer’s disease, age-related macular degeneration, and glaucoma. Furthermore, we have found that mice in which APOE has been targeted only in myeloid cells (microglia and peripheral monocytes/macrophages) are protected from microbead-induced glaucoma. We hypothesize that APOE controls the switch of retinal microglia from homeostatic to a harmful neurodegenerative phenotype, and that in the absence of APOE, microglia remain in the homeostatic state, leading to a decreased retinal neuroinflammatory response and RGC degeneration following intraocular pressure (IOP) elevation. We will address this hypothesis in the following specific aims: 1) Determine the functional impact of microglia-specific APOE targeting in glaucoma. In this aim, we will address whether selective ablation of APOE in microglia utilizing tamoxifen-inducible Cx3cr1-CreERT2 APOEfl/fl mice leads to behavioral and functional neuroprotection after IOP induction, as assessed by optokinetic response, electroretinogram, and visual evoked potential testing. 2) Investigate the mechanism by which APOE signaling contributes to glaucoma pathogenesis. We will investigate the hypothesis that targeting APOE in microglia maintains these cells in the homeostatic state, resulting in decreased apoptotic neuron phagocytosis and cytokine production. 3) Characterize the role of human APOE isoforms in the mouse model of glaucoma. By using novel humanized-floxed APOE e2, e3 and e4 mice, we will investigate the hypothesis that mice with APOE e4 allele exhibit an altered microglial molecular signature and are less susceptible to RGC loss after microbead-induced IOP elevation. The research outlined in this proposal will serve to investigate the role of APOE signaling in microglia in glaucoma, with the ultimate goal of developing novel neuroprotective treatments for this common blinding disease. This research addresses an understudied area of neuroinflammation in glaucoma while also preparing me for a successful career as an independent clinician-scientist.

该建议描述了一个为期3年的培训计划，以开发专注于学术职业 了解视网膜神经炎症在青光眼中的作用。我的研究目标是阐明 小胶质细胞，视网膜和大脑中的居民免疫细胞，在青光眼的发病机理中。我们的初步 数据表明，在微片青光眼模型中，小胶质细胞抑制稳态基因并诱导A 与脑神经退行性疾病共享疾病相关的分子特征（MGND）。在 增加促炎细胞因子和神经毒性物质的诱导，也是MGND小胶质细胞 明显上调了APOE的产生，APOE是大脑中主要的脂蛋白。最近发现了Apoe 严重调节脑小胶质细胞中的MGND分子特征，并与阿尔茨海默氏症相关 疾病，与年龄相关的黄斑变性和青光眼。此外，我们发现的老鼠 APOE仅针对髓样细胞（小胶质细胞和周围单核细胞/巨噬细胞）。 来自微珠诱导的青光眼。我们假设APOE控制着视网膜小胶质细胞的转换 对有害神经退行性表型的稳态，并且在没有APOE的情况下，小胶质细胞仍然存在 稳态状态，导致残留神经炎症反应和RGC变性下降 后压（IOP）升高后。我们将在以下具体目的中解决这一假设： 1）确定小胶质细胞特异性APOE靶向青光眼中的功能影响。在这个目标中，我们将 解决使用他莫昔芬诱导的CX3CR1-CREERT2 APOEFL/FL/FL的选择性消融小胶质细胞中的ApoE 小鼠导致IOP诱导后的行为和功能性神经保护 响应，电子图和视觉诱发的潜在测试。 2）研究APOE信号传导有助于青光眼发病机理的机制。我们将 研究以下假设：小胶质细胞中的apoE将这些细胞保持在稳态状态， 导致凋亡神经元吞噬作用和细胞因子产生减少。 3）表征人APOE同工型在青光眼小鼠模型中的作用。通过使用小说 人源化的APOE E2，E3和E4小鼠，我们将研究具有APOE E4等位基因的小鼠的假设 表现出改变的小胶质分子签名，在微片诱导后不太容易受到RGC的损失 IOP海拔。 该提案中概述的研究将有助于研究ApoE信号在小胶质细胞中的作用 青光眼，最终目标是为这种常见的盲目开发新的神经保护疗法 疾病。这项研究介绍了青光眼中神经炎症的知识领域，同时还准备 我从事独立临床科学家的成功职业。