Lymphatic vessel enlargement in patients with psoriasis. (A) Clinically uninvolved skin from patients with psoriasis showed normal patterns of blood (red; CD31) and lymphatic (green; LYVE-1) vessels. (B) Psoriatic skin was characterized by multiple enlarged blood vessels in the upper dermis adjacent to the thickened epidermis and by highly enlarged lymphatic vessels (arrows). Representative pictures from the lower back are shown. Scale bar: 100 μm.