Previously, we and others have shown that IAPP is present in Aβ deposits in the human brain (Jackson et al., 2013; Oskarsson et al., 2015), and proximity ligation assay (PLA) was used to confirm co-localization of Aβ and IAPP in amyloid deposits in both cortex and blood vessel walls of AD patients (Oskarsson et al., 2015). Here, IAPP is linked to Alzheimer disease.