Fig. 1.

PDGFRα⁺ mammary cells are a stromal adipogenic population enriched in progenitors. a Maximum intensity Z-projection of confocal immunofluorescence for luminal (K8; red) and basal (K14; green) epithelial-specific keratins with PDGFRα (magenta) and nuclear DAPI (blue) on a representative adult mouse mammary tissue section (n = 3 mice, 5 fields per section); scale bar = 25 µm. b Droplet digital PCR analysis of Pdgfrα and epithelial keratins K14, K18 normalized to Gapdh in fluorescence-activated cell sorting (FACS)-sorted stromal (CD49f^-EpCAM^-, n = 5) and luminal (CD49f^loEpCAM⁺, n = 4), basal (CD49f^hiEpCAM⁺, n = 3) mammary epithelial cells. c FACS gating strategy used to exclude doublets and dead cells (PI⁺) from analysis of PDGFRα⁺ cells within the lineage⁺ (Lin⁺) population that consists of haematopoietic (CD45⁺), endothelial (CD31⁺) cells and erythrocytes (Ter119⁺), and the Lin^- population that consists of mammary stromal and epithelial subpopulations segregated using indicated cell surface markers; fluorescence minus one (FMO) control. d Flow cytometry analyses of PDGFRα⁺ cells within distinct mammary subpopulations derived from adult mammary glands of untreated or sex hormone (E+P) treated mice (n = 3 mice per group). e Quantification of PDGFRα⁺ cells in (d). f Image of adipocyte differentiation and lipid accumulation in FACS-sorted PDGFRα⁺ cells as detected by Oil Red O staining (representative of cultured sorted cells from n=6 individual mice); scale bar = 100 µm. g Colony forming cell (CFC) assay performed on sorted PDGFRα^- and PDGFRα⁺ stromal cells (n = 6 mice); scale bar = 5 mm. h Representative stromal colonies generated by PDGFRα⁺ cells (n = 6 mice); scale bar = 200 µm. i CFC capacity of PDGFRα^- and PDGFRα⁺ cells (n = 3 mice). Data represent mean ± s.e.m. *p< 0.05, **p<0.01, ***p<0.001 (t-test). Source data are provided as a Source Data file