The potential to reconstitute LCs resides preferentially in the fraction of CLPs and CMPs expressing the Flt3 receptor. (A) Histograms in upper panel show CD45.1 expression profile of total epidermal cells derived from CD45.2 mice reconstituted with 10⁴ CD45.1 CMPs or CLPs either expressing or lacking Flk2. Contour plots show CD11c/I-A^b expression profile of gated donor (CD45.1⁺) epidermal cells derived from the respective progenitor populations. Epidermal cells were analyzed for the presence of progenitor-derived LCs at 2 weeks (CMPs) or 3 weeks (CLPs). Percentages of LCs derived from transplanted cells (CD45.1⁺) or host cells (CD45.1^-) are indicated. (B) Epidermal sheets from mice were prepared from mice that received transplants of 10⁴ CD45.1⁺ CMPs (Flk2⁺ or Flk2^-) at 2 weeks after transplantation and from mice reconstituted with either 10⁴ CD45.1 Flk2⁺ CLPs or CD45.1 Flk2^- CLPs at 3 weeks after transplantation. Shown are the overlays of photomicrographs obtained after immunofluorescence staining of epidermal sheets with anti-CD45.1-PE (red) and anti-I-A^b-FITC (green). Scale bar: 100 μm. Data are representative of at least 3 transplantations for each progenitor population with similar results. (C) Chart shows average LC reconstitution (% of total LCs) obtained per 10⁴ progenitor cells (Flk2⁺, Flk2^-, or unseparated) at 2 weeks (CMP populations) and 3 weeks (CLP populations) after adoptive transfer. Data are representative of at least 3 transplantations per progenitor population with similar results.