Fig. 4

Contribution of AF-1⁰, AF-2⁰ and ERα^−/− cells to chimeric ducts with WT MECs. a Scheme of experimental design. After cell dissociation, 10,000 ERα mutant (ERmt) or WT GFP⁺ epithelial cells were mixed with 90,000 WT.DsRed⁺ epithelial cells and injected into the cleared mammary fat pad of peripubertal recipient mice. b Representative fluorescence stereomicrographs of chimeric epithelia from WT.GFP⁺ or ERα.mutant.GFP⁺ and WT.DsRed⁺ cells mixed in a 1:10 ratio. Hosts were analysed 10 weeks after engraftment. Scale bars; 1 mm (left) 0.2 mm (right). c Pie charts showing the proportion of engrafted mammary glands appearing exclusively DsRed⁺, exclusively GFP⁺, or mixed (red and green stripes) based on evaluation at low (7.8×) magnification of fluorescence stereomicrographs. From top to bottom, n = 51, 21, 17 and 13. d Dot plot showing the percentage of the reconstituted ductal epithelium that is GFP⁺ in virgin mice based on images at 7.8× magnification, (n = 13–51) bars indicate medians. e Dot plot showing the ratio of GFP/DsRed signal intensity of the reconstituted ductal epithelia based on images at 7.8× magnification, bars indicate medians (n = 29, 15, 7 and 7). f, g Bar graphs showing flow cytometric analysis of the percentage of GFP⁺ cells in the CD24^high CD49f^low f and CD24^low CD49f^high g cell populations of reconstituted chimeric mammary epithelia. From left to right, n = 20, 5, 8 and 6. Shown are means ± SEM; Mann–Whitney test, two-tailed, ^**p < 0.01, ^****p < 0.0001, n.s. not significant