A Novel Multiparameter Blood Test for Early Detection of Alzheimer's Disease

项目摘要 我们的目标是开发一种基于血液的诊断方法，用于阿尔茨海默病的症状前检测 (Ad)基于多参数分析(前置放大器)。 目前全世界有超过1800万例AD病例，预计病例数量将增加近一倍 在未来的15年里。仅在美国，每年的总经济成本估计接近2000亿美元1。 诊断是复杂、昂贵和耗时的。部分原因是缺乏诊断工具，以及 AD代表具有重叠症状和蛋白质的神经退行性疾病的连续体 病理学。由于这些原因，约58%的痴呆症被认为完全没有被诊断出来，这导致 许多患者得不到充分、及时的护理或治疗。最近的研究表明，不同形式的 在AD患者的大脑中常见的聚集蛋白也可以在血液中检测到，这表明 承诺开发一种基于血液的诊断方法。然而，到目前为止，不同的研究强调 单标记物优于多参数方法，对于哪一个标记物优于3-9没有达成共识。 因此，多参数生物标记物检测可能被证明是非常有价值的早期诊断。 针对一系列痴呆症的不同患者。 绝大多数生物标记物的努力都集中在无毒变体的检测上，而不是实际的 参与神经退行性变的有毒聚集蛋白物种。最近，我们的项目组开发了 新的生物扫描技术使我们能够产生单链抗体可变区抗体 (ScFv)与AD及相关的四个关键神经元蛋白的疾病特异性变体结合 痴呆：Tau、Aβ、Tdp-43和α-syn。我们的单链抗体只对大脑和 来自ADRD患者的血浆样本，但不是认知正常对照10-12。Aβ和TdP-43水平 我们的四个单链抗体识别的寡聚体在最初诊断为轻度糖尿病前数年显著升高。 认知障碍(MCI)9。在疾病发展过程中，我们发现生物标记物的特征会改变，所以我们的 基于抗体的诊断也可以用于AD从症状前期到晚期的进展阶段 阶段，允许对患者进行临床分层，以支持ADRD9的实验性治疗决策。 在这项工作的基础上，这项建议旨在开发一种基于血液的AD诊断方法，称为PREAMP。 其具体目的是：1)建立一种用于血浆蛋白定量的小体积、多重抗体检测方法。 变种。2)确定AD症状前诊断的最佳生物标志物集合；3)验证检测方法 纵向AD患者样本的盲法回顾研究中的表现。

Project Summary Our objective is to develop a blood-based diagnostic for Pre-symptomatic detection of Alzheimer's disease (AD) based on a Multiparameter Profiling (PreAMP). Currently there are over 18 million cases of AD worldwide, with the number of cases expected to nearly double over the next 15 years. In the US alone, total economic costs are estimated at nearly $200 billion per year1. Diagnosis is complex, costly and time-consuming. In part because of the lack of diagnostic tools and because AD represents a continuum of neurodegenerative disorders that share overlapping symptoms and protein pathologies. For these reasons, ~58% of dementia is thought to be undiagnosed altogether, which result that many patients do not receive adequate, timely care or treatment2. Recent work has revealed that forms of the aggregated proteins commonly found in the brains of AD patients can also be detected in the blood, showing promise for the development of a blood-based diagnostic. So far, however, different studies have emphasized single markers over a multiparameter approach, with no consensus as to which marker is superior3-9. Therefore, a multiparameter biomarker assay may prove to be extremely valuable for early diagnosis of a diverse range of patients against a continuum of dementias. The vast majority of biomarker efforts have focused on detection of non-toxic variants rather than the actual toxic aggregated protein species involved in neurodegeneration. Recently, our project team has developed novel biopanning technologies that enabled us to generate single chain antibody variable domain antibodies (scFvs) that bind to disease-specific variants of four key neuronal proteins implicated in AD and Related Dementias (ADRD): tau, Aβ, TDP-43, and α-syn. Our scFvs react only to the variants found in brain and plasma samples from ADRD patients but not cognitively normal controls10-12. Levels of Aβ and TDP-43 oligomers recognized by four of our scFvs were significantly elevated years before an initial diagnosis of mild cognitive impairment (MCI)9. During disease progression, we found that biomarker profiles change, so our antibody-based diagnostic could also be used to stage progression of AD from pre-symptomatic through late stage, permitting clinical stratification of patients to support experimental therapy decision-making for ADRD9. Building from this work, this proposal is designed to develop a blood-based diagnostic for AD called PreAMP. The specific aims are to: 1) develop a low-volume, multiplex antibody assay for quantitation of plasma protein variants. 2) determine the optimal biomarker set for pre-symptomatic diagnosis of AD, 3) validate the assay performance in a blinded retrospective study of longitudinal AD patient samples.