High-sensitivity Immunomagnetic System for "Liquid Biopsy" of Alzheimer's Disease

用于阿尔茨海默病“液体活检”的高灵敏度免疫磁系统

• 批准号: 10539340
• 负责人: Hui Mao
• 金额: $ 56.65万
• 依托单位: EMORY UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-02-01 至 2025-12-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10539340
• 关键词: Address; Adsorption; Alzheimer disease detection; Alzheimer' s Disease; Alzheimer' s disease patient; Alzheimer’s disease biomarker; Amyloid beta-42; Amyloid beta-Protein; Amyloid beta-Protein Precursor; Antibodies; Archives; Attenuated; Biological Markers; Blocking Antibodies; Blood; Blood specimen; Brain; Brain imaging; Cerebrospinal Fluid; Clinical; Clinical Management; Communities; Coupled; Data; Detection; Development; Devices; Diagnosis; Disease Progression; Early Diagnosis; Economic Burden; Enhancement Technology; Enzyme-Linked Immunosorbent Assay; Equipment; Goals; Healthcare; Image; Imaging Techniques; Immunomagnetic Separation; In Vitro; Individual; Ligands; Liquid substance; Magnetic Resonance Imaging; Magnetism; Measurement; Measures; Microfluidic Microchips; Microfluidics; Microspheres; Microtubules; Monitor; Nanotechnology; Noise; Patient Care; Patients; Plasma; Polymers; Population; Population Heterogeneity; Positron-Emission Tomography; Prognostic Marker; Protein Analysis; Proteins; Proteomics; Radioactive; Research; Resources; Risk; Sampling; Scanning; Sensitivity and Specificity; Serum; Specificity; Surface; System; Technology; Testing; Time; abeta deposition; antibody conjugate; biomarker discovery; cost; cost effective; detection platform; diagnostic accuracy; diagnostic biomarker; diagnostic tool; early screening; effective therapy; improved; in-vitro diagnostics; innovation; iron oxide; liquid biopsy; multiplex detection; nano; nanoparticle; nanorod; nanosized; nanotechnology platform; neuroimaging; peripheral blood; point of care; programs; radiotracer; social; surface coating; targeted biomarker; tau Proteins; tau-1

Project Summary Alzheimer’s disease (AD) is a major healthcare and social-economic burden. With effective treatment yet to be developed, the early detection at the prodromal stage and surveillance of the progression are the best approach to control and intervene AD development. While non-invasive positron emission tomography (PET) can measure amyloid-β peptides (Aβs) and microtubule tau proteins in the brain to confirm the onset of AD, the availability of imaging equipment, diagnostic accuracy of single Aβ or tau specific radiotracer and the cost and exposure of radioactive materials limit imaging applications from early screening of large and diverse populations and repeated scans in monitoring disease progression. Therefore, there is an unmet need in developing robust, accessible and cost-effective in vitro diagnostic tools for detecting and measuring the levels of Aβs and tau proteins in cerebrospinal fluid or even blood samples of patients or at-risk individuals at the “point-of-care”. However, serum detection of these AD biomarker demands high sensitivity because of low concentrations of Aβs or tau proteins in blood samples and slow and gradual change of the levels of these biomarkers during disease progression. One major challenge to the current biospecimen based in vitro diagnostics is the biofouling effect, i.e., adsorption of proteins and biomolecules on the surface of the detecting agents and devices. This leads to the formation of the layer of unwanted molecules, which reduces the detection specificity and sensitivity by (1) blocking antibodies to the targeted biomarkers, and (2) causing high “background noise” from adsorbed non-specific proteins and other molecules interfering the detection of targeted biomarkers. We believe that these problems can be overcome by our innovative solutions, i.e., 1) the anti-biofouling polymer to coat nanoparticle capturing agents to block the non-specific protein adsorption, thus protecting the sensitivity and specificity of the targeting ligands/antibodies; 2) high magnetism magnetic iron oxide nanorods (IONRs) with nano-sized magnetic stir bar action to enhance mixing of capturing agents and targeted biomarkers in the microfluidic detection system. By integrating these technologies, our project aims to develop a multiplexing based “liquid biopsy” system with ultra-high sensitivity and specificity for serum detection of selected AD biomarkers, Aβ40, Aβ42, total-tau (tTau), phosphorylated-Tau (pTau)181 and amyloid precursor protein (APP) in one sample. We will make and optimize antibody-conjugated anti-biofouling IONRs with different aspect ratios for highly efficient fluid mixing and multiplex detection of spiked Aβ40, Aβ42, tTau and pTau proteins and APP669-711 in blood samples (Aim 1), coupled with developing a microfluidic device with effective nano-stir bar mixing for improved detection efficiency (Aim 2), and then evaluate and validate the developed “liquid biopsy” system by multiplexed measuring serum Aβ40, Aβ42, tTau, pTau proteins and APP669-711 levels in AD patients longitudinally, and comparing and correlating the serum measurement with results from Aβ and tau PET imaging and proteomics analysis done on the same patients (Aim 3).

项目摘要 阿尔茨海默病 (AD) 是一项重大的医疗保健和社会经济负担。 有效的治疗方法尚待开发，前驱阶段的早期发现和监测 进展是控制和干预 AD 发展的最佳方法，而非侵入性正电子。 发射断层扫描 (PET) 可以测量大脑中的淀粉样β肽 (Aβ) 和微管 tau 蛋白， 确认 AD 的发病、成像设备的可用性、单个 Aβ 或 tau 特异性的诊断准确性 放射性示踪剂以及放射性材料的成本和暴露限制了早期筛查的成像应用 因此，需要对大量且多样化的人群进行重复扫描来监测疾病进展。 开发强大、易于使用且具有成本效益的体外诊断工具来检测和治疗的需求尚未得到满足 测量患者或高危人群脑脊液甚至血液样本中 Aβ 和 tau 蛋白的水平 然而，这些 AD 生物标志物的血清检测需要高灵敏度。 由于血液样本中 Aβ 或 tau 蛋白的浓度较低，并且 Aβ 或 tau 蛋白的变化缓慢且逐渐 当前基于生物样本的一大挑战是疾病进展期间这些生物标志物的水平。 体外诊断是生物污垢效应，即蛋白质和生物分子在物体表面的吸附 这会导致不需要的分子层的形成，从而减少 通过 (1) 阻断针对目标生物标志物的抗体，以及 (2) 引起检测的特异性和灵敏度 来自吸附的非特异性蛋白质和其他干扰检测的分子的高“背景噪音” 我们相信这些问题可以通过我们的创新解决方案来克服，即 1) 抗生物污染聚合物涂覆纳米颗粒捕获剂以阻止非特异性蛋白质吸附，从而 保护靶向配体/抗体的敏感性和特异性2)高磁性磁铁； 氧化物纳米棒（IONR）具有纳米级磁力搅拌棒作用，可增强捕获剂和 通过整合这些技术，我们的项目旨在微流体检测系统中的目标生物标记物。 开发基于多路复用的“液体活检”系统，对血清具有超高灵敏度和特异性 检测选定的 AD 生物标志物、Aβ40、Aβ42、总 tau (tTau)、磷酸化 Tau (pTau)181 和淀粉样蛋白 我们将在一份样品中制备和优化抗体偶联的抗生物污染 IONR。 具有不同的纵横比，可实现高效流体混合和加标 Aβ40、Aβ42、tTau 的多重检测 以及血液样本中的 pTau 蛋白和 APP669-711（目标 1），同时开发具有 有效的纳米搅拌棒混合以提高检测效率（目标 2），然后评估和验证 开发了“液体活检”系统，通过多重测量血清 Aβ40、Aβ42、tTau、pTau 蛋白和 AD 患者中 APP669-711 水平的纵向分析，并将血清测量值与 对同一患者进行 Aβ 和 tau PET 成像和蛋白质组学分析的结果（目标 3）。