Plasma biomarkers for Alzheimer's disease: from amyloid to CNS derived extracellular vesicles, overview of changes through age, sex and risk factor in control and AD populations

摘要: Background Hallmark proteins pathogenic in Alzheimer's disease (AD), amyloid and tau, can now be quantified in plasma samples using single‐molecule array (SIMOA). However, proteins are not only circulating in plasma, but are also present in nervous system‐derived extracellular vesicles (NDBEs) secreted by neurons in the plasma. We aim to quantify plasmatic NBDEs to evaluate whether their number or content are modified in symptomatic AD. Method Plasma samples were obtained in clinically normal (CN) participants (N = 76, sex ratio F/M = 1.5, mean age 57.5 ± 16.3, Apoε4 positive n=31, Apoε4 negative n=43) and in patients with symptomatic AD (N=17, sex ratio F/M = 0.7, mean age 70.1 ± 7.6). Quantification of amyloid 42 – 40 peptides and Tau protein was achieved with SIMOA multiplex analysis. For relative quantification of NDBEs circulating in plasma, we used DELFIA ELISA immunoassay with …