Transcriptional analyses identify pericyte-centered signaling programs altered by sex and brain region in Alzheimer's Disease.

Pericytes are critical components of the neurovascular unit (NVU), regulating endothelial cell stability, blood-brain barrier (BBB) integrity, and neuroimmune signaling. Their role in Alzheimer's Disease (AD), particularly regarding sex differences and brain region specificity, remains poorly defined. Using single-nucleus RNA sequencing analysis and cell-cell communication tools (LIANA, Tensor-cell2cell), we characterize pericyte transcriptional and signaling changes across the middle temporal gyrus (MTG) and dorsolateral prefrontal cortex (DLPFC) of AD and non-AD donors stratified by sex. We identify a pericyte-endothelial TGFβ signaling program upregulated in female AD donors specifically in the MTG, and a downregulated estrogen pathway involving pericyte-astrocyte ligand-receptor interactions, supported by increased pericyte-astrocyte separation in spatial transcriptomics. We also identify a microglia-to-pericyte program enriched for hypoxia and p53 pathways that is elevated in both sexes with regional specificity. Our findings implicate pericyte-driven communication as a mechanistic contributor to female-biased AD vulnerability, and support sex- and region-aware approaches in neurodegeneration research.