Alzheimer's disease (AD) is an incurable neurodegenerative disease characterized by progressive decline of cognitive abilities. Amyloid beta peptides (Aβ), Tau proteins and the phosphorylated form of the Tau protein, p-Tau, are the core pathological biomarkers of the disease, and their detection for the diagnosis of patients is progressively being implemented. However, to date, their quantification is mostly performed on cerebrospinal fluid (CSF), the collection of which requires an invasive lumbar puncture. Early diagnosis has been shown to be important for disease-modifying treatment, which is currently in development, to limit the progression of the disease. Nevertheless, the diagnosis is often delayed to the point where the disease has already progressed, and the tools currently available do not allow for a systematic follow-up of patients. Thus, the search for a molecular signature of AD in a body fluid such as blood or saliva that can be collected in a minimally invasive way offers hope. A number of methods have been developed for the quantification of core biomarkers, especially in easily accessible fluids such as the blood, that improve their accuracy, specificity and sensitivity. This review summarizes and compares these approaches, focusing in particular on their use for Aβ detection, the earliest biomarker to be modified in the course of AD. The review also discusses biomarker quantification in CSF, blood and saliva and their clinical applications.

中文翻译：

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检测体液中的淀粉样β肽以诊断阿尔茨海默氏病：我们站在哪里？

阿尔茨海默氏病（AD）是一种不可治愈的神经退行性疾病，其特征是认知能力逐渐下降。淀粉样蛋白β肽（Aβ），Tau蛋白和Tau蛋白的磷酸化形式p-Tau是该疾病的核心病理生物标志物，其检测患者的诊断方法正在逐步实施。然而，迄今为止，它们的量化主要在脑脊液（CSF）上进行，其收集需要进行有创腰椎穿刺术。业已证明，早期诊断对疾病改良治疗很重要，目前这种疾病正在发展中，以限制疾病的进展。然而，诊断通常会延迟到疾病已经进展的程度，并且当前可用的工具无法对患者进行系统的随访。因此，寻找可以以微创方式收集的诸如血液或唾液之类的体液中AD的分子标记提供了希望。已经开发出许多用于定量核心生物标记物的方法，特别是在诸如血液等易于获取的液体中，可提高其准确性，特异性和敏感性。这篇综述总结并比较了这些方法，尤其着重于将它们用于Aβ检测的研究，Aβ检测是在AD过程中最早被修饰的生物标志物。该综述还讨论了脑脊液，血液和唾液中的生物标志物定量及其临床应用。已经开发出许多用于定量核心生物标记物的方法，特别是在诸如血液等易于获取的液体中，可提高其准确性，特异性和敏感性。这篇综述总结并比较了这些方法，尤其着重于将它们用于Aβ检测的研究，Aβ检测是在AD过程中最早被修饰的生物标志物。该综述还讨论了脑脊液，血液和唾液中的生物标志物定量及其临床应用。已经开发出许多用于定量核心生物标记物的方法，特别是在诸如血液等易于获取的液体中，可提高其准确性，特异性和敏感性。这篇综述总结并比较了这些方法，尤其着重于将它们用于Aβ检测的研究，Aβ检测是在AD过程中最早被修饰的生物标志物。该综述还讨论了脑脊液，血液和唾液中的生物标志物定量及其临床应用。