Langerhans cells may trigger the psoriatic disease process via production of nitric oxide.

Psoriasis is a skin disease that appears to result from a dysfunction in the normal mechanism(s) that regulates wound healing. The Langerhans cell is a specialized epidermal macrophage that may instigate wound healing via production of nitric oxide and epidermal growth factor. Here, Vera Morhenn suggests that, whereas precise coordination of the synthesis of these two substances regulates normal wound healing, a disturbance of this regulation could lead to psoriasis.