Directional proteome analysis of extracellular vesicles in AD models

阿尔茨海默病（Alzheimer's disease，AD）是一种严重的神经退行性痴呆，与A β和Tau蛋白有关 目前在美国有540万人患有大脑病理学。AD的主要假设是 A β/淀粉样蛋白假说，该假说认为A β的积累是一个早期和必要的事件， 促进tau蛋白病、线粒体和突触功能障碍的致病性进展，以及 神经炎症，导致突触和神经元损失。新出现的证据表明， 从一个细胞到另一个细胞的细胞外囊泡（EV）的摄取代表了细胞间相互作用的重要形式。 这是一种可以在不同细胞之间传递有益或致病信号的通信。我们的初步数据 表明A β 42寡聚体和突变Tau显著改变EV释放（外泌体& 微泡）。尽管有这些显著的变化，EV蛋白质组的具体变化和相互作用的 并且特定神经元隔室和小胶质细胞之间的定向效应是未知的。此外，鉴于 EV在生物液体如血浆中丰富，脑源性EV蛋白质组的改变 提供了从血浆中开发新的生物标志物的独特机会。我们的假设是 AD病理驱动因素显著改变EV蛋白质组（外泌体和MV）以及它们的 致病性通过局部和非局部机制，这些变化在EV蛋白质组的大脑将 用作血浆中有用的病理学和疾病特异性生物标志物。在本提案中，我们将1）概述 并验证了来自神经元/小胶质细胞培养物的EV在响应AD致病性时的蛋白质组变化 驱动因子和2）确定分离的A β 42处理衍生的外泌体的局部和定向致病性 从神经元和小胶质细胞的互动环境中。因此，这些研究的结果将提供关键的 深入了解A β 42，Tau和小胶质细胞在EV和EV释放中的相互作用和定向作用 蛋白质及其致病性，同时确定AD中EV蛋白质组的主要变化 致病环境这些信息共同将有助于识别基于EV的AD生物标志物 并建立一个平台，用于广泛的功能表征病理衍生的EV及其 蛋白质组含量

Alzheimer’s disease (AD) is a devastating neurodegenerative dementia associated with A and Tau pathologies in brain that currently afflicts 5.4 million individuals in the USA. The major hypothesis of AD is the A/amyloid hypothesis, which states that the accumulation of A is an early and necessary event in the pathogenic progression that promotes tauopathy, mitochondrial & synaptic dysfunction, and neuroinflammation, leading to synaptic and neuronal loss. Emerging evidence indicates that the release and uptake of extracellular vesicles (EVs) from one cell to another represent an important form of intercellular communication that could transmit beneficial or pathogenic signals across different cells. Our preliminary data indicate that A42 oligomers and mutant Tau dramatically alter the release of EVs (exosomes & microvesicles). Despite these significant changes, the specific changes in the EV proteome and the interactive and directional effects between specific neuronal compartments and microglia are unknown. Moreover, given that EVs are abundant in biological fluids such as plasma, alterations in the proteome of brain-derived EVs provides the unique opportunity to develop novel biomarkers from blood plasma. Our working hypothesis is that AD pathological drivers significantly alter the EV proteome (exosomes & MVs) as well as their pathogenicity via local and nonlocal mechanisms and that those changes in the EV proteome of brain will serve as useful pathology and disease-specific biomarkers in blood plasma. In this proposal, we will 1) profile and validate the changes in proteome of EVs from neuron/microglia cultures in response to AD pathogenic drivers and 2) determine the local and directional pathogenicity of A42 treatment-derived exosomes isolated from the interactive milieu of neurons and microglia. Therefore, the results of these studies will provide critical insights to the interactive and directional effects of A42, Tau, and microglia in the release of EVs and EV proteins as well as their pathogenicity, while identifying the major changes in the EV proteome in the AD pathogenic setting. Such information collectively will aid in the identification of EV-based biomarkers for AD and establish a platform for extensive functional characterization of pathologically-derived EVs and their proteome content.