MAPT and amyloidosis: In support of synergistic interactions, Bassil and colleagues demonstrated that the unilateral hippocampal injection of mouse αsyn PFF (mPFF) into the aggressive 5xFAD amyloid model leads to more severe and widespread αsyn pathology, hyperphosphorylated tau detection, hippocampal and midbrain neuronal loss, and cognitive and motor deficits [217].