WSB.APP/PS1 mice develop age-dependent cerebral amyloid angiopathy, cerebrovascular dysfunction, and white matter deficits

INTRODUCTION: Cerebrovascular deficits, including cerebral amyloid angiopathy (CAA), play a key role in Alzheimer's disease (AD) pathogenesis. Here, we characterize the susceptibility of the WSB/EiJ genetic context to human AD-relevant cerebrovascular phenotypes. METHODS: CAA and parenchymal plaque analysis and in vivo neurovascular imaging were performed on WSB.APP/PS1 brains. Transcriptomics was performed on WSB.APP/PS1 and B6.APP/PS1 brains. B6 and WSB cerebrovascular reactivity was assayed ex vivo. Additional CAA and parenchymal plaque analysis was performed on WSB.APP/PS1 mice with APOE², APOE³, or APOE⁴ alleles. RESULTS: WSB.APP/PS1 brains exhibited plaque deposition, CAA, transcriptomic overlap with human AD, myelin deficits, cerebrovascular/metabolic uncoupling, and altered cerebrovascular morphology. Aged WSB vasculature retained vasoreactivity but exhibited increased stiffness. Compared to WSB.APOE2/2APP/PS1, WSB.APOE4/4APP/PS1 mice had increased CAA and plaque-associated microglial area. DISCUSSION: These data illustrate the utility of the WSB genetic context to model CAA and uncover vascular contributions to AD.