In AD patients, astrocytes and microglia react with Aβ plaques, cerebral amyloid angiopathy-laden arteries and capillaries, as well as neurofibrillary tangles, and therefore activate transcription of APOE in microglia, down-regulation in astrocytes, and dysregulation of lipid metabolism [11,17,18]. Here, APOE is linked to cerebral amyloid angiopathy.