Towards understanding the role of immune regulation of Apolipoprotein E function in Alzheimer's disease proteostasis

了解载脂蛋白 E 功能的免疫调节在阿尔茨海默氏病蛋白质稳态中的作用

• 批准号: 9643985
• 负责人: PARAMITA CHAKRABARTY
• 金额: $ 38.13万
• 依托单位: UNIVERSITY OF FLORIDA
• 依托单位国家: 美国
• 财政年份: 2017
• 资助国家: 美国
• 起止时间: 2017-03-15 至 2023-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/9643985
• 关键词: AD transgenic mice; Address; Affect; Age; Alleles; Alzheimer like pathology; Alzheimer' s Disease; Alzheimer' s disease model; Alzheimer' s disease risk; Alzheimer' s disease therapy; Amyloid; Amyloid beta-Protein; Anti-Inflammatory Agents; Antigen-Antibody Complex; Apolipoprotein E; Behavioral; Binding; Biological; Brain; CX3CL1 gene; Cell-Free System; Code; Cognition; Complex; Coupled; Data; Deposition; Disease; E protein; Genes; Genotype; Gliosis; Goals; Human; Immune; Immune signaling; Immunologic Receptors; Impairment; Inflammatory; Innate Immune System; Interleukin-10; Interleukin-10 Overexpression; Interleukin-4; Knock-out; Knowledge; Literature; Maps; Mediating; Microglia; Modeling; Molecular Chaperones; Mus; Natural Immunity; Nerve Degeneration; Neurodegenerative Disorders; Neuroimmune; Pathogenesis; Pathogenicity; Pathologic; Pathology; Pathway interactions; Phagocytosis; Phenotype; Physiological; Play; Pre-Clinical Model; Property; Prosencephalon; Protein Isoforms; Proteins; Recombinant adeno-associated virus (rAAV); Reporting; Research Design; Research Personnel; Rodent Model; Role; Senile Plaques; Series; Signal Pathway; Signal Transduction; Study models; System; Systems Biology; Tauopathies; Technology; Testing; Therapeutic; Time; Toll-like receptors; Transgenic Mice; Transgenic Organisms; Ursidae Family; Work; apolipoprotein E-2; base; cognitive function; cohort; cytokine; design; efficacy testing; experience; experimental study; genetic risk factor; genomic locus; immune activation; immunomodulatory strategy; immunoregulation; inhibition of autophagy; insight; interest; interleukin-10 receptor; link protein; mouse model; pre-clinical; proteostasis; receptor; risk variant; systematic review; tau Proteins; tool; transcriptomics; uptake; β-amyloid burden

The goal of our proposal is to determine the role of the master regulatory cytokine, Interleukin 10 (IL10), in regulating proteostasis in mouse models of Alzheimer’s disease (AD) in an Apolipoprotein E (ApoE) isoform dependent manner. Our proposal addresses two key questions that are relevant to understanding of AD pathogenesis: (1) how does immune pathways interact with and modulate the function of AD risk genes, such as APOE and (2) can we harness this knowledge to disrupt the IL-10/APOE axis and achieve therapeutic benefits in AD-relevant mouse models? Our preliminary data has shown that the anti-inflammatory cytokine Interleukin (IL)-10, has unexpected negative effect on Aβ and tau proteostasis in transgenic mouse models of AD. This demonstrates a complex interplay between innate immunity and proteostasis in AD type neurodegenerative diseases, an interaction we call immunoproteostasis. The mechanism(s) underlying such immunoproteostasis leading to neurodegenerative pathology in AD remain unknown; studying the mechanisms underlying immunoproteostasis can enable us to design immunobiotherapies targeting such signaling pathways. We have observed that overexpression of IL-10 in APP transgenic mice worsens Aβ plaque pathology and cognitive functions via an ApoE-dependent mechanism. Mechanistically, we could attribute the negative effects of IL-10 on Aβ proteostasis to synergistic effects of decreased Aβ phagocytosis by microglia, increased endogenous ApoE expression and enhanced accumulation of ApoE in insoluble amyloid plaques. In our study, the increased level of insoluble ApoE was plaque-associated, consistent with mouse ApoE functioning as a pathological chaperone for Aβ aggregates. Blocking IL-10 signaling using the soluble decoy receptor against IL-10 abrogated this effect and reduced brain amyloid plaque burden. We observed similar ApoE dependent effects on tau proteostasis following IL-10 overexpression in two independent mouse models of tauopathy. Essentially, IL-10 accelerated tauopathy and reduced time to survival in JNPL3 mice; it also promoted forebrain neurodegeneration and tauopathy in the rTg4510 mice. While this was an unexpected phenotype, we provide preliminary data that ApoE specifically interacts with fibrillar tau in a cell free system, which could partially explain the proteostasis, though other mechanisms, such as autophagy inhibition also need to be considered. Guided by these robust preliminary data, we will undertake the following specific aims: Aim 1. Assess whether APOE genotype affects IL10-induced proteostasis in APP mice and evaluate whether interaction of human APOE isoforms with Aβ aggregates alters microglial clearance of insoluble Aβ. We will test the effects of IL- 10 immunoproteostasis on amyloid plaque deposition in an APP transgenic mouse expressing human APOE protein (2 or 3 or 4) and provide mechanistic insights into APOE-dependent microglial uptake and clearance of aggregated Aβ. We expect that promoting expression of the protective APOE2 isoform will have beneficial effects while APOE4 induction will have harmful effects. Aim2. Determine the effects of an AAV-delivered soluble IL-10 receptor decoy (sIL10R1) strategy in APP, tau and non- transgenic mice. Given that IL-10 worsens proteostasis and AD-relevant phenotype in mouse models of Aβ and tau, herein, we will test the efficacy of a decoy receptor strategy against IL-10. By blocking IL-10 signaling, we expect the decoy receptor strategy to be a potentially translatable disease modifying therapy against both Aβ and tau proteostasis. Aim3. Replicate and extend our studies of IL-10 overexpression as a driver of tau pathology. Herein, using the AAV toolkit, and systems biology approach, we propose to reproduce our observations of IL-10/APOE-dependent proteostasis phenotype in a well-controlled and behaviorally-characterized tau transgenic cohort and further provide insights into possible mechanisms underlying such amyloidogenic properties of the IL-10/APOE axis. The strength of this proposal lies in the teamwork between a new investigator with continuing commitment to studying the neuroimmune axis in mouse models of AD and an established investigator with experience in creating transgenic AD mouse models. We expect that this proposal will enhance our knowledge of the complex immune signaling cascades in AD proteostasis and uncover translatable immune decoy receptor strategies targeting APOE-regulated proteostasis.

我们提案的目标是确定主要调节细胞因子白细胞介素 10 (IL10) 在调节中的作用 阿尔茨海默病 (AD) 小鼠模型中的蛋白质稳态以载脂蛋白 E (ApoE) 亚型依赖性方式实现。 我们的提案解决了与理解 AD 发病机制相关的两个关键问题：（1）免疫如何影响 AD 发病机制？ 通路与 AD 风险基因（例如 APOE）相互作用并调节其功能，（2）我们可以利用它吗？ 破坏 IL-10/APOE 轴并在 AD 相关小鼠模型中获得治疗效果的知识？ 我们的初步数据表明，抗炎细胞因子白细胞介素（IL）-10，具有意想不到的负面影响 AD 转基因小鼠模型中 Aβ 和 tau 蛋白稳态的影响。这表明先天之间存在着复杂的相互作用 AD 型神经退行性疾病中的免疫和蛋白质稳态，我们将这种相互作用称为免疫蛋白质稳态。这 这种免疫蛋白稳态导致 AD 神经退行性病变的机制仍然未知； 研究免疫蛋白稳态的机制可以使我们能够设计针对此类疾病的免疫生物疗法 信号通路。 我们观察到 APP 转基因小鼠中 IL-10 的过度表达会恶化 Aβ 斑块病理学和认知能力 通过 ApoE 依赖机制发挥作用。从机制上讲，我们可以将 IL-10 对 Aβ 的负面影响归因于 蛋白质稳态与小胶质细胞 Aβ 吞噬作用减少、内源 ApoE 表达增加的协同作用 并增强 ApoE 在不溶性淀粉样斑块中的积累。在我们的研究中，不溶性 ApoE 水平增加 与斑块相关，与小鼠 ApoE 作为 Aβ 聚集体的病理伴侣的功能一致。阻塞 使用针对 IL-10 的可溶性诱饵受体进行 IL-10 信号传导消除了这种效应并减少了脑淀粉样斑块 负担。我们在两个细胞中观察到 IL-10 过表达后对 tau 蛋白稳态的类似 ApoE 依赖性影响 独立的tau蛋白病小鼠模型。从本质上讲，IL-10 加速了 JNPL3 中的 tau 蛋白病变并缩短了生存时间 老鼠；它还促进 rTg4510 小鼠的前脑神经变性和 tau 蛋白病变。虽然这出乎意料 表型，我们提供了 ApoE 在无细胞系统中与纤维状 tau 特异性相互作用的初步数据，这 可以部分解释蛋白质稳态，尽管还需要研究其他机制，例如自噬抑制 经过考虑的。在这些可靠的初步数据的指导下，我们将实现以下具体目标： 目标 1. 评估 APOE 基因型是否影响 APP 小鼠中 IL10 诱导的蛋白质稳态，并评估是否存在相互作用 人 APOE 亚型与 Aβ 聚集体的结合会改变小胶质细胞对不溶性 Aβ 的清除。我们将测试IL-的效果 10 表达人 APOE 蛋白（2 或 3 或 4) 并提供对 APOE 依赖性小胶质细胞摄取和聚集 Aβ 清除的机制见解。我们 预计促进保护性 APOE2 同工型的表达将在 APOE4 诱导的同时产生有益效果 会产生有害影响。 目标2。确定 AAV 递送的可溶性 IL-10 受体诱饵 (sIL10R1) 策略对 APP、tau 和非 转基因小鼠。鉴于 IL-10 会恶化 Aβ 和 tau 小鼠模型中的蛋白质稳态和 AD 相关表型， 在此，我们将测试针对 IL-10 的诱饵受体策略的功效。通过阻断 IL-10 信号传导，我们预计 诱饵受体策略成为一种潜在的可转化的针对 Aβ 和 tau 蛋白稳态的疾病修饰疗法。 目标3。重复并扩展我们关于 IL-10 过度表达作为 tau 病理学驱动因素的研究。这里，使用AAV 工具包和系统生物学方法，我们建议重现我们对 IL-10/APOE 依赖性蛋白质稳态的观察结果 在良好控制和行为特征的 tau 转基因队列中观察表型，并进一步提供见解 IL-10/APOE 轴的此类淀粉样蛋白生成特性的可能机制。 该提案的优势在于新研究者之间的团队合作，并继续致力于研究 AD 小鼠模型中的神经免疫轴以及具有创建转基因 AD 经验的知名研究者 鼠标模型。我们期望该提案将增强我们对复杂免疫信号级联的了解 AD 蛋白质稳态并揭示针对 APOE 调节的蛋白质稳态的可翻译免疫诱饵受体策略。