The authors would like to acknowledge K. Probst and N Sirivansanti for creating schematics for the summary figure, Fig. 1, and Fig. 3. Funding: National Institutes of Health grant U54NS065705 (E.A.W., H.K., S.W.); National Institutes of Health grant R01NS034949 (H.K.); National Institutes of Health grant R01NS099268 (H.K.); National Institutes of Health grant R01EB012031 (K.N.); National Institutes of Health grant R01NS034467 (B.V.Z.); National Institutes of Health grant 5P01AG052350 (B.V.Z.); National Institutes of Health grant R01NS112357 (D.A.L.); National Institutes of Health grant F32CA228372 (E.A.W.); National Institutes of Health grant U01MH115747 (T.J.N.); Brain Aneurysm Foundation grant (E.A.W.); Veterans Affairs Merit award (D.A.L.); Gifts from the William K. Bowes Jr Foundation, the Shurl and Kay Curci Foundation, and Schmidt Futures (T.J.N.). Author contributions: Conceptualization: E.A.W., C.N.K., D.L.C., M.T.L., B.V.Z., A.A.A., D.A.L., and T.J.N. Methodology: E.A.W., C.N.K., I.O., L.Q.C., and T.J.N. Formal analysis: E.A.W., C.N.K., J.M.R., I.O., L.Q.C., and T.J.N. Investigation: E.A.W., C.N.K., J.M.R., J.H.G., E.G., I.O., L.Q.C., D.W., J.S.C., K.R., and K.N. Visualization: E.A.W., J.M.R, and C.N.K. Resources: A.A.A., E.F.C., M.T.L., and N.G. Funding acquisition: E.A.W., H.K., B.P.W., N.G., and T.J.N. Project administration: E.A.W., H.K., S.W., D.A.L., and T.J.N. Supervision: A.A.A., D.A.L., and T.J.N. Writing—original draft: E.A.W., C.N.K., T.N., and D.A.L. Writing—review and editing: E.A.W., C.N.K., J.S.C., K.R., K.N., H.K., D.L.C., M.T.L., N.G., B.V.Z., D.A.L., and T.J.N. Competing interests: Authors declare they have no competing interests. Data and materials availability: Data are available to explore via an interactive cell viewer: https://adult-brain-vasc.cells.ucsc.edu. Sequencing data have been deposited at dbGAP phs002624.v2.p1. All code is available at https://github.com/cnk113/vascular-analysis (86). All other data are available in the main text or the supplementary materials.