(F) Higher magnification of boxed regions in E shows reduced staining for H3 in nevus (bottom panels), compared with epidermalmelanocytes (top panels). Bars, 20 µm. (G) Quantitative immunofluorescence of H3 in epidermal and nevusmelanocytes. Images were obtained in blue (DAPI), green (S100), and red (H3) channels and then H3 intensity was measured in either S100+epidermal cells, strictly adjacent to the basal membrane, or in S100+nevusmelanocytes. H3 intensity histograms represent fluorescence intensity distribution, combined from three individual nevi. At least 150 epidermal (50 per nevus) and 300 nevus (100 per nevus) melanocytes were assessed. 