Double immunofluorescent staining with IL-17 and Foxp3 in skin biopsies of patients with acute, chronic, and no GVHD. (A) Skin biopsies showed infiltrates and apoptotic bodies (arrows) in acute and chronic lichenoid eruption but not in patients without GVHD. (B) Overlay of double immunofluorescent staining with IL-17 (red) and Foxp3 (green) antibodies showed Foxp3 expressing cells in skin biopsies of patients with acute and chronic GVHD and IL17-expressing cells in skin biopsies of patients without GVHD. (C) Enlargement of the stained cells showed that none of them expressed both IL-17 and Foxp3.