Human primary LCs express IL-15R-α. (A) Epidermal sheets from healthy skin were cultured in complete RPMI-10% NHS. GM-CSF 1000 IU/mL was added or not to maintain LC viability.21 The cells recovered in culture after 40 to 48 hours were cytocentrifuged, fixed and permeabilized, and stained as indicated for IL-15R-α (red), HLA-DR (green), and 4,6-diamidino-2-phenylindole (blue nuclear DNA stain). Scale bars represent 10 μm. (B) At least 20 cells in randomly selected fields from each donor/condition were evaluated to calculate the average voxels, which represent digitalized 3-dimensional image data. Shown in the bar graph are the averaged replicate means from 3 independent experiments ± SEM. *P = .0254. Error bar not shown for the condition without GM-CSF, as lower viability yielded sufficient cells from only 2 independent experiments.
