Novel 3D brain tissue-based screening assay for targeting microglia in CNS neurodegeneration

小胶质细胞活化与CNS神经退行性变相关的神经炎症 据报道，它们会进一步造成损害，或对疾病有保护作用， 进展因此，靶向小胶质细胞在新药开发中的翻译潜力， CNS神经退行性疾病仍不确定。这方面的一个主要挑战是 相关的小胶质细胞表型和激活状态非常难以 在细胞系模型中或甚至在小胶质细胞的原代培养物中重现。相反，小胶质细胞 体内研究是时间和成本密集型的，因此具有有限的可扩展性。 为了满足这一需求，我们建议开发并验证一种新的脑组织- 的药物发现模型，用于新药的鉴定和机理评价， 用于调节CNS神经变性疾病中小胶质细胞活化的药物靶候选物。 脑组织模型捕捉了完整的局部脑组织中细胞间相互作用的重要方面。 3-天然神经组织的三维结构，从而具有增加的生理功能， 相关性，并且与基于细胞的模型相比可以更好地预测临床益处。 此外，我们以前已经表明，脑切片分析可以扩展到有用的吞吐量 用于亨廷顿病（HD）、阿尔茨海默病（AD）和中风的药物发现。 因此，本提案的目标是建立大脑的实验框架， 小胶质细胞-神经元相互作用的基于切片的筛选和机制测定，并提供 初步验证小胶质细胞激活和/或数量的扰动导致了明确的 对神经变性的速率和/或程度的可再现的影响。此外，我们会延长 检测外周单核细胞的潜在作用，其浸润与 中枢神经系统疾病的晚期。我们将首先关注我们使用的HD脑切片模型 在筛选和机制研究中广泛使用，然后询问我们的发现是否 可推广到由淀粉样前体蛋白驱动的CNS神经变性的不同模型 和分别与AD和额颞痴呆（FTD）相关的tau亚型。 如果成功的话，这些研究将提供一个新的基于三维脑组织的模型， 捕获临床相关的小神经胶质细胞-神经元相互作用， 新的候选药物和药物靶点的发现CNS神经退行性变， 机械评估和验证。

Aspects of microglial activation in neuroinflammation associated with CNS neurodegeneration have alternately been reported to be further damaging or to be protective against disease progression. Thus, the translational potential of targeting microglia in new drug development for CNS neurodegenerative diseases remains uncertain. A major challenge in this context has been that relevant microglial phenotypes and activation states have been exceedingly difficult to recapitulate in cell line models or even in primary cultures of microglia. Conversely, microglial studies in vivo are time- and cost-intensive, and consequently have limited scalability. To address this need, we propose to develop and provide validation for a novel, brain tissue- based drug discovery model for the identification and mechanistic evaluation of new drug and drug target candidates for modulating microglial activation in CNS neurodegenerative disorders. Brain tissue models capture important aspects of intercellular interactions within the intact, local 3-dimensional structure of native neural tissues, and thereby have increased physiological relevance and can be more predictive of clinical benefit compared to cell-based models. Moreover, we have shown previously that brain slice assays can be scaled to useful throughputs for drug discovery in Huntington's disease (HD), Alzheimer's disease (AD), and stroke. The goal of the present proposal is thus to establish the experimental framework for a brain slice-based screening and mechanistic assay for microglial-neuronal interactions, and to provide initial validation that perturbation of microglial activation and/or numbers leads to clear and reproducible effects on rates and/or extents of neurodegeneration. In addition, we will extend the assay to interrogate potential effects of peripheral monocytes, whose infiltration is associated with later stages of CNS disease. We will initially focus on an HD brain slice model that we have used extensively in both screening as well as mechanistic studies, and then ask if our findings are generalizable to different models of CNS neurodegeneration driven by amyloid precursor protein and tau isoforms relevant to AD and frontotemporal dementias (FTD), respectively. If successful, the proposed studies should provide a new 3-D brain tissue-based model for capturing clinically relevant microglial-neuronal interactions scalable to screening throughputs for the discovery of new candidate drugs and drug targets for CNS neurodegeneration, and for their mechanistic evaluation and validation.