Demonstration of human cell engraftment in ESS <i>in vivo</i>.

Immunohistochemistry was performed using an antibody against HLA-ABC (green) to localize human keratinocytes in ESS after grafting to mice. Merkel cells were visualized by staining with an antibody against KRT20 (red). Nuclei were counterstained using DAPI (blue; C, F, I). Sections are oriented with the epidermis at the top of each image. Note that images in each row depict a single section. A-C, ESS at 4 weeks after grafting. D-F, ESS at 8 weeks after grafting. G-I, ESS from 12 weeks after grafting. Arrows indicate examples of KRT20-positive Merkel cells in grafted human ESS. Scale bar in A is same for all sections (50 μm).