MRC1 and Alzheimer disease: To identify brain myeloid cell subsets associated with AD pathology, we analyzed the percentage of myeloid cell nuclei per cluster from high and low-pathology donors, including microglia and perivascular macrophages (PvMs) as identified by marker genes LYVE1, MRC1, F13A1, and CD163. We reasoned that AD-associated brain myeloid cell clusters should have a significantly higher proportion of nuclei from high vs. low-pathology donors and/or correlate positively with any of the local tau and Aβ pathology readouts.