H&E staining demonstrates characteristic features of psoriasis (right), with epidermal acanthosis, elongation of rete ridges, parakeratosis (retention of nuclei in stratum corneum), enlarged blood vessels, and marked leukocytic dermal infiltrate. Immunohistochemistry of non-lesional and lesional psoriatic skin for Langerhans cells (Langerin), resident dermal DCs (CD1c/ BDCA-1+), resident and inflammatory myeloid DCs (CD11c), and plasmacytoid DCs (BDCA-2). Insert is a high power magnification of each cell type and is approximately 60μm length. Size bar = 100μm.