Figure 3.

Mouse epidermal progenitor cells expanded by TGF-β inhibition are capable of differentiation in response to Ca²⁺ stimulation in vitro. (a) Representative images of newborn mouse-derived, RepSox-expanded P18 epidermal cells before (upper) and after (lower) treatment with 0.3 mM Ca²⁺ for 3 days. Bar = 25 μm. (b) Quantitative RT-PCR analysis of epidermal cell differentiation marker genes. Newborn mouse-derived, RepSox-expanded P17 epidermal cells were induced to differentiate by treatment with 0.3 mM Ca²⁺ (for CK1, CK10, Lor, Flg, and Ivl) or 1.3 mM Ca²⁺ (for p63) for 0–3 days as indicated. Data shown are normalized to the housekeeping gene Gapdh and expressed as mean ± s.e.m. (n = 3). *P < 0.05; **P < 0.01; ***P < 0.005; ns, not significant. (c) Western blot analysis using antibodies against p63, CK10, loricrin (LOR), and involucrin (IVL). Newborn mouse-derived, RepSox-expanded P17 epidermal cells were induced to differentiate by the treatment with 0.3 mM Ca²⁺ for 0 (Ctrl) and 3 (Ca²⁺) days. Tubulin-α (Tub) was used as a loading control. The full-length blots are included in Supplementary Figure S12.