A novel blood-CSF adaptive immune response in Alzheimer's disease

阿尔茨海默病（AD）是一种无法治愈的神经退行性疾病，神经炎症在其中起着至关重要的作用。虽然先天炎症与阿尔茨海默病有关，但对适应性免疫反应的贡献知之甚少。本应用程序的初步数据表明，AD的外周免疫特征以高度分化的CD8+ T效应记忆CD45RA+ (TEMRA)细胞数量增加为特征。引人注目的是，患者脑脊液（CSF）中也存在CD8+ TEMRA细胞，T细胞受体（TCR）测序显示它们的克隆扩增，表明这些适应性免疫细胞具有抗原特异性。TCR克隆和肽筛选表明，克隆扩增的AD CSF TCR亚群对eb病毒（EBV） BZLF1抗原具有特异性。这些结果提供了克隆的第一个证据，抗原经历的T细胞巡逻脑鞘内空间受年龄相关性神经变性的影响。这项K99/R00应用将测试有害适应性免疫反应促进AD病理生物学的新理论。在Specific Aim 1中，AD血-CSF T细胞克隆型将与CSF生物标志物相关。这种方法将确定AD中的特定T细胞群以及这些细胞是否与疾病严重程度有关。在Specific Aim 2中，抗原鉴定筛选将用于检测AD中驱动T细胞克隆扩增的自身/非自身抗原。这些检测可能会发现一种新的AD治疗靶点或生物标志物。特异性Aim 3将通过诱导神经元（in）细胞与患者CSF CD8+ T细胞共培养，确定AD中T细胞介导的神经元死亡和恢复机制。这些实验将评估AD CSF CD8+ T细胞是否对感染EBV和/或BZLF1分子模拟物的iN细胞产生细胞毒效应反应。候选人David Gate博士在T细胞生物学方面拥有丰富的经验，并花了十多年的时间研究AD。在该奖项的指导阶段，Gate博士旨在提高他在下一代测序分析、复杂统计方法、抗原筛选、in培养方法和CRISPR基因编辑方面的知识。Gate博士的导师和共同导师Tony Wyss-Coray博士和Mark Davis博士分别在这些领域拥有全面的专业知识。他们将为盖茨博士提供丰富的环境，使他成为神经免疫学研究领域的杰出独立研究者。作为一名独立研究者，Gate博士将利用该奖学金下的培训，全面定量地评估T细胞分子成分与神经变性之间的相互作用。

Alzheimer’s disease (AD) is an incurable neurodegenerative disorder in which neuroinflammation is increasingly recognized to play a critical function. While innate inflammation has been implicated in AD, little is known about the contribution of the adaptive immune response. Preliminary data featured in this application demonstrate a peripheral immune signature of AD characterized by increased numbers of highly differentiated CD8+ T effector memory CD45RA+ (TEMRA) cells. Strikingly, CD8+ TEMRA cells were also present in-patient cerebrospinal fluid (CSF) and T cell receptor (TCR) sequencing indicated their clonal expansion, suggesting antigen specificity of these adaptive immune cells. TCR cloning and peptide screens demonstrated specificity of a subset of clonally expanded AD CSF TCRs to the Epstein-Barr virus (EBV) BZLF1 antigen. These results provide the first evidence of clonal, antigen-experienced T cells patrolling the intrathecal space of brains affected by age-related neurodegeneration. This K99/R00 application will test the novel theory of a detrimental adaptive immune response contributing to AD pathobiology. In Specific Aim 1, AD blood-CSF T cell clonotypes will be related to CSF biomarkers. This approach will determine specific T cell populations in AD and whether these cells relate to disease severity. In Specific Aim 2, antigen identification screens will be used to detect the self/non-self-antigen(s) driving T cell clonal expansion in AD. These assays could uncover a novel therapeutic target or biomarker for AD. Specific Aim 3 will determine mechanisms of T cell-mediated neuronal death and resiliency in AD using induced neuronal (iN) cells co-cultured with patient CSF CD8+ T cells. These experiments will assess whether AD CSF CD8+ T cells mount cytotoxic effector responses to iN cells infected with EBV and/or to a molecular mimic of BZLF1. The candidate, Dr. David Gate, has extensive experience in T cell biology and has spent more than a decade studying AD. During the mentoring phase of this award, Dr. Gate aims to advance his knowledge in next-generation sequencing analysis, sophisticated statistical methods, antigen screening, iN culturing methods and CRISPR gene editing. Dr. Gate's mentor and co-mentor, Dr. Tony Wyss-Coray and Dr. Mark Davis, respectively, have comprehensive expertise in these areas. They will provide an enriching environment for Dr. Gate to develop as a prominent independent investigator in neuroimmunology research. As an independent investigator, Dr. Gate will leverage the training under this fellowship to comprehensively and quantitatively evaluate the interactions between T cell molecular components and neurodegeneration.