Optimization and Validation of an Indicator Cell Assay for Blood-Based Diagnosis of Alzheimer's Disease

项目摘要。 PreCyte 正在开发指示细胞检测平台 (iCAP)，作为一种广泛适用和 廉价的基于血液的检测，可用于疾病的早期检测、疾病阶段分层、 预后和预测对多种疾病治疗的反应。 iCAP 使用经过培养的、标准化的 细胞作为生物传感器，利用细胞对血清中存在的疾病信号做出反应的能力 与依赖直接检测血液中分子的传统检测不同，其灵敏度极高。 开发 iCAP 涉及将培养的细胞暴露于正常或患病受试者的血清中，测量 全局差异反应模式，并用它来构建基于表达的可靠疾病分类器 少量的基因。部署 iCAP 只涉及测量分类基因的表达 使用具有成本效益的工具的功能。我们已经展示了用于肺癌血液检测的 iCAP 以及在临床前和早期症状阶段检测阿尔茨海默病 (AD)。 在 SBIR 第二阶段研究中，与系统生物学研究所、传染病中心合作进行 PreCyte 与疾病研究中心和西雅图生物医学和临床研究所合作开发了 iCAP- AD 能够在多个队列的临床前和早期症状阶段检测 AD。对于这个 IIb 期， 我们建议开发并验证临床 iCAP AD，这是 iCAP 的高通量且廉价版本 用于快速选择 AD 疗法临床试验的受试者。通过简单的血液测试，临床 AD iCAP 将 能够从 60 岁及以上的受试者群体中进行选择，这些受试者要么患有临床前疾病，要么患有早期疾病 有症状的 AD 和针对非 AD 痴呆症的特异性，并且可能具有额外的能力来识别 这些候选人中的一部分将在 2 年内进入 AD。临床开发和验证 iCAP-AD 将实现四个具体目标：1) 开发临床 iCAP-AD，2) 建立关键检测的限制 证明测定稳健性的参数，3) 验证临床 iCAP 的分析特征，以及 4) 验证临床 iCAP 的诊断特征。该提案的目标是降低使用风险 基于细胞的测定，并建立一个强大且经过验证的平台，用于选择 AD 临床试验受试者 和患者诊断。在 CLIA 环境中实施后，该工具将显着降低成本和 通过快速选择早期受试者来缩短 AD 治疗临床试验的持续时间，有可能 确定那些在 2 年内患 AD 的人。它还将提高开发有效的 AD 治疗，因为它能够针对处于疾病临床前和早期症状阶段的患者， 已被证明比后期更容易治疗，也可用于监测 AD 进展和治疗反应。

Project Summary. PreCyte is developing the Indicator Cell Assay Platform (iCAP) as a broadly applicable and inexpensive blood-based assay that can be used for the early detection of disease, disease stage stratification, prognosis and predicting response to therapy for a variety of diseases. The iCAP uses cultured, standardized cells as biosensors, capitalizing on the ability of cells to respond to disease signals present in serum with exquisite sensitivity, as opposed to traditional assays that rely on direct detection of molecules in blood. Developing the iCAP involves exposing cultured cells to serum from normal or diseased subjects, measuring a global differential response pattern, and using it to build a reliable disease classifier based on the expression of a small number of genes. Deploying the iCAP involves measuring only expression of genes that are classifier features using cost-effective tools. We have demonstrated the iCAP for blood-based detection of lung cancer and detection of Alzheimer's disease (AD) at preclinical and early symptomatic stages. In the SBIR Phase II study, conducted in collaboration with the Institute for Systems Biology, Center for Infectious Disease Research, and Seattle institute of Biomedical and Clinical Research, PreCyte has developed an iCAP- AD capable of detecting AD at preclinical and early symptomatic stages in multiple cohorts. For this Phase IIb, we propose to develop and validate a clinical iCAP AD, a high-throughput and inexpensive version of the iCAP for rapidly selecting subjects for clinical trials of AD therapies. From a simple blood test, the clinical AD iCAP will be able to select from a population of subjects 60 years and older, those with either preclinical or early symptomatic AD and specificity against those with non-AD dementia, and may have additional capacity to identify a subset of these candidates who will progress to AD within 2 years. Development and validation of the clinical iCAP-AD will be done in four specific aims: 1) Develop the clinical iCAP-AD, 2) Establish limits for key assay parameters to demonstrate assay robustness, 3) Validate analytical characteristics of the clinical iCAP, and 4) Validate diagnostic characteristics of the clinical iCAP. The goal of this proposal is to mitigate the risks of using a cell-based assay and establish a robust and validated platform for use in selecting subjects for AD clinical trials and patient diagnosis. After implementation in a CLIA environment, this tool will significantly reduce cost and shorten the duration of clinical trials for AD treatments by rapidly selecting early-stage subjects, with potential to identify those who are within 2 years of developing AD. It will also improve success rate of developing an effective treatment for AD as it enables the targeting of patients at preclinical and early symptomatic stages of the disease, which have been demonstrated to be more treatable than later stages, and could also be used for monitoring AD progression and response to treatment.