Aβ3pE-42–positive signals corresponding to PiB-binding sites were detected preferentially in the core of amyloid plaques, whereas Aβ1-42–positive signals were observed in larger amyloid plaques (Fig 5A) and the PiB binding was increased in Mme−/−APP-Tg mice in a manner colocalizing with N3pE-positive cored plaques in a significant way (Fig 5B, left panel, and Fig 5C). Here, MME is linked to amyloidosis.