Four fluid-based biomarkers have been developed into diagnostic tests for Alzheimer’s disease (AD) pathology: the ratio of 42 to 40 amino acid-long amyloid β, a marker of plaque pathology; total-tau and phosphorylated tau, markers of AD-related changes in tau metabolism and secretion; and neurofilament light, a marker of neurodegeneration. When measured in cerebrospinal fluid, these biomarkers can be used in clinical practice to support a diagnosis of mild cognitive impairment or dementia due to AD. Recently, technological breakthroughs have made it possible to measure them in standard blood samples as well. Here, we give an updated account of the current state of the fluid-based AD biomarker research field. We discuss how the new blood tests may be used in research and clinical practice, and what role they may play in relation to more established diagnostic tests, such as CSF biomarkers and amyloid and tau positron emission tomography, to facilitate the effective implementation of future disease-modifying therapies.

中文翻译：

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将阿尔茨海默病的液体生物标志物从研究工具转移到常规临床诊断

四种基于液体的生物标志物已被开发用于阿尔茨海默病 (AD) 病理学的诊断测试：42 到 40 个氨基酸长的淀粉样蛋白 β 的比率，斑块病理学的标志物；总 tau 和磷酸化 tau，tau 代谢和分泌中 AD 相关变化的标志物；和神经丝光，一种神经退行性变的标志物。当在脑脊液中测量时，这些生物标志物可用于临床实践以支持 AD 引起的轻度认知障碍或痴呆的诊断。最近，技术突破使得在标准血液样本中测量它们成为可能。在这里，我们对基于流体的 AD 生物标志物研究领域的当前状态进行了更新。我们讨论如何在研究和临床实践中使用新的血液检测，