MAPT and early-onset autosomal dominant Alzheimer disease: However, the selective packaging of brain-derived extracellular vesicles (BDEVs) hasn’t been well documented with few studies demonstrating the presence of disease-associated proteins in BDEVs, such as α-synuclein in dementia with lewy bodies (DLB), Aβ and phosphorylated tau in DLB and Alzheimer’s disease (AD) and toxic oligomer Aβ in AD [57,58,59].