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

小胶质细胞激活在中枢神经系统退行性变相关神经炎中的作用 交替地被报告为进一步破坏或对疾病具有保护作用 进步。因此，靶向小胶质细胞在新药开发中的翻译潜力 中枢神经系统退行性疾病仍不确定。在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已经非常困难 在细胞系模型中，甚至在小胶质细胞的原代培养中进行总结。相反，小胶质细胞 体内研究是时间和成本密集型的，因此可扩展性有限。 为了满足这一需求，我们建议开发并验证一种新型的脑组织-- 基于新药发现模型的新药识别与机理评价 中枢神经系统退行性疾病中调节小胶质细胞激活的候选药物。 脑组织模型捕捉了完整的、局部的细胞间相互作用的重要方面 天然神经组织的三维结构，从而增加了生理性 相关性，与基于细胞的模型相比，可以更好地预测临床益处。 此外，我们以前已经证明，脑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)和中风的药物研发。 因此，本提案的目标是建立大脑的实验框架 基于切片的小胶质细胞-神经元相互作用的筛选和机制分析，并提供 初步验证小胶质细胞激活和/或数量的扰动导致明确和 对神经退行性变的速度和/或程度的可重复性影响。此外，我们还将延长 检测外周血单核细胞的潜在作用，其渗透与 中枢神经系统疾病的晚期。我们首先将重点放在我们使用的HD脑切片模型上 在筛查和机械研究中广泛使用，然后询问我们的发现是否 对淀粉样前体蛋白诱导的不同中枢神经系统变性模型的通用性 Tau亚型分别与AD和额颞叶痴呆(FTD)相关。 如果成功，拟议的研究将提供一个新的基于3-D脑组织的模型 捕获临床相关的小胶质细胞-神经元相互作用，可扩展到筛选吞吐量 治疗中枢神经系统退行性变的新候选药物和药物靶点的发现 机械化的评估和验证。

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.