MAPT and early-onset autosomal dominant Alzheimer disease: NCAM has been used as a neuronal marker for the immunocapture of nEVs from plasma in several previous studies which compared levels of Alzheimer disease-related proteins such as tau and amyloid beta 42 (Aβ42) in nEVs from patients and healthy controls to determine their potential use as biomarkers of disease [14,15,26,27].