Extended Data Fig. 1. FACS analysis of MG epithelial cells.

a–d, Unicellular suspension of MG cells from adult K5CreER/tdTomato/K8rtTA/TetO-DTA mice induced at 8 weeks stained for endothelial, immune and fibroblast markers (Lin⁺) (CD31, CD45, CD140a) in APC, EpCAM in Apc-Cy7 and CD29 in FITC, were gated to eliminate debris (a), doublets were discarded with gates (b), the living cells were gated by DAPI dye exclusion (c) and the non-epithelial Lin⁺ cells were discarded (d). CD24/CD29 and EpCAM/CD29 expression was studied in Lin⁻. e–g, CD24/CD29 gates, EpCAM/CD29 gates and the absence of leakiness of fluorescent reporter recombination before tamoxifen injection (e), after tamoxifen injection (f) and after DOX injection (g). The CD29^low CD24^high and the CD29^low EpCAM^high gate corresponds to LCs, the CD29^high CD24^low and the CD29^high EpCAM^low gate corresponds to BCs, the CD29^high EpCAM^high correspond to the new population described in this manuscript. A total of 400,000 events is shown in the graphs. Percentages are calculated on the total LCs and BCs or LCs, CD29^high EpCAM^high and BCs shown. n = 3 independent experiments per condition. h, Graph showing the percentage of BCs that were tdTomato-labelled on the total number of BCs gated on CD24/CD29 before DOX injection (79.5 ± 2.2%; n = 20 mice, data are mean ± s.e.m.) after DOX injection (CD24 83.9 ± 2.6%; n = 23 mice, data are mean ± s.e.m.) and EpCAM/CD29 before DOX injection (84.8 ± 2.2%; n = 20 mice, data are mean ± s.e.m.) and after DOX injection (88.9 ± 1.9%; n = 23 mice, data are mean ± s.e.m.). P values are derived from unpaired two-sided t-tests.