The number of AT8 intensely stained neurons in the mice injected with AD p-Tau was several-fold higher than that in the mice injected with saline in both the ipsilateral and contralateral hippocampus, suggesting that AD p-Tau was taken up by neurons at the injection site and that the Tau pathology from the seeded neurons of the ipsilateral hippocampus spread to the contralateral hippocampus (Fig. 4a and b). Here, MAPT is linked to Alzheimer disease.