Fig 2: Establishment of human epidermal stem cell (EpSC) Culture. a Schematic overview of tissue processing, EpSC culturing, and extracellular vesicle analysis. b Representative images show the generation of human EpSCs (scale bar 100 µm). c Immunostaining of COL17A1, K14, K10, ITGB1, Ki67, PLEC, and ITGA6 in human skin (scale bar 100 µm). d Immunostaining of K14, DSC2, ITGB1, DSG1, and ITGA6 in EpSCs (scale bar 100 µm). All biological experiments were repeated three times (n = 3, biological replicates)

Fig 3: Epidermal stem cell (EpSC)-derived extracellular vesicles mediate EpSC development. a Transmission electron microscopy (TEM) and western blot analysis of EpSC-derived extracellular vesicles. b Schematic of percentage of cell components in EpSC-derived extracellular vesicles. Tissue expression (c) and biological process (d) analysis of EpSC-derived extracellular vesicles. e Schematic of cellular component and biological process in spatial function of the epidermis. The depth of the color indicates protein abundance according to log2 normalized protein intensity of EpSC-derived extracellular vesicles. f Interaction network between ITGB1 and other proteins of EpSC-derived extracellular vesicles. g Selected cellular pathways of hemidesmosome and focal adhesion. h Western blot analysis of KRT10, KRT14, ITGB1, ITGA6, ERK1, ICAM1, and ECAD in EpSCs and EpSC-derived vesicles. All biological experiments were repeated three times (n = 3, biological replicates)