MAPT and Alzheimer disease: In support of this, the inhibition of exosome biosynthesis or microglia depletion was shown to suppress tau propagation in mouse models of tauopathy and to improve learning and memory in the 3xTg-AD mouse model (APP Swedish, MAPT P301L, and PSEN1 M146V; Asai et al., 2015; Dagher et al., 2015).