MAPT and Alzheimer disease: In AD, EVs have been proposed to contribute to the spread of Aβ and Aβ pathology in the brain (Rajendran et al., 2006) as well as the spread of hyper-phosphorylated pathogenic tau between neurons (Saman et al., 2012; Wang et al., 2017; Guix et al., 2018; Winston et al., 2019).