Figure 2.
Immunohistochemical localization of p40 in psoriatic skin. The four panels are from frozen sections of human skin from psoriasis patients. A and B are IgG isotype controls in uninvolved and lesional skin, respectively. C and D are stained with mouse anti–human IL-12p40 as indicated. The arrow indicates morphology consistent with DCs. The color represents 3-amino-9-ethylcarbazole deposition at the site of antibody binding. Melanin appears in A as dark stain in the basal cell layer.