Fig 2. The CD1a⁺ dDC subset is the phenotypically most mature human skin APC subset under steady conditions.

A. Subset distribution in percentages of CD1a⁺ and CD14⁺ dermal cells (upper panel) or CD1a⁺ LCs (lower panel) after gating on isolated HLA-DR⁺ cells. Dot plots of a representative experiment are shown. N = 8. B. Surface expression of MHC class I and II, CD86 and CD83 was measured by flow cytometry on isolated HLA-DR⁺CD14⁺ cells, HLA-DR⁺CD1a⁺ dDCs and HLA-DR⁺CD1a^high LCs. Grey histograms depict matching isotype controls. Histograms of a representative experiment are shown. N = 3. C. Relative mRNA levels of CD83 and CD86 compared to the housekeeping gene GAPDH are shown present in FACS-sorted, steady state DN, CD14⁺ or CD1a⁺ dermal cells and LCs. Due to low cell numbers of each subset after sorting, the subsets contain combined cells of at least 4 skin donors. Mean values ± SEM; n = 3. ***p<0.001, as measured by the one-way ANOVA followed by the Bonferroni multiple comparison test.