Fig. 2: Loss of Mcam promotes MEC regenerative capacity.

a Immunostaining of K14 (red) and Ki67 (green) expression in mammary ducts and TEBs of WT and cKO mice by MMTV-Cre. Scale bar, 10 μm. b Ki67⁺ cells in basal and luminal cell populations of mammary ducts and TEBs in WT and cKO mice. n = 10 sections in each group. c, d FACS analysis (c) and statistical ratios of basal cell population (Lin⁻CD24⁺CD29⁺) and luminal cell population (Lin⁻CD24⁺CD29^-) (d) in WT and cKO mice. n = 6 mice for each genotype. e Representative images (left) and the reconstitution efficiency at limiting dilution (right) of whole-mount-stained mammary outgrowths derived from transplantation of isolating WT or cKO Lin^- cells and harvested at 6 weeks after transplantation. Scale bar, 5 mm. n = 8 mice for each group. f Representative images (left) and the reconstitution efficiency at limiting dilution (right) of whole-mount-stained mammary outgrowths derived from transplantation of WT or cKO basal cells and harvested at 6 weeks after transplantation. Scale bar, 5 mm. n = 5 in 200-cell of cKO group, n = 6 mice in the other groups. g–i Representative images (g), clone numbers (h, n = 6 biological replicates), and clone diameters (i, n = 93 for WT and n = 125 for cKO by MMTV-Cre) of colonies formed by MECs derived from WT and cKO mice. Scale bar, 500 μm. Data are means ± SEM. Two-sided Student’s t test was used to evaluate statistical significance. Source data are provided as a Source Data file.