Final answer:
Psoriasis is a skin disease characterized by itchy or sore patches of thick, red skin with silvery scales. It can affect various parts of the body and may be accompanied by psoriatic arthritis. The condition results from a complex interplay between keratinocytes, dendritic cells, and T cells.
Step-by-step explanation:
Psoriasis is a skin disease that causes itchy or sore patches of thick, red skin with silvery scales on elbows, knees, scalp, back, face, palms, feet, and sometimes other areas. Some individuals with psoriasis also get a form of arthritis called psoriatic arthritis, in which the joints can become inflamed. Psoriasis results from the complex interplay between keratinocytes, dendritic cells, and T cells, and the cytokines produced by these various cells.