Suppressor cell function in psoriasis.

Recent studies suggest that autoimmunity may play a role in the pathogenesis of psoriasis. In view of these findings, it is postulated that the immunologic defect may be associated with regulation of the immune system. A study was undertaken to determine whether a suppressor cell defect was present. Two groups of patients with active psoriasis who were receiving no therapy were selected. Peripheral blood lymphocytes were pulsed with concanavalin A, 40 microgram/cc, for 48 hours. Their ability to suppress a mixed lymphocyte reaction with both autologous and allogeneic responding cells was assessed. There was a significant decrease in suppressor activity in psoriasis patients compared with normal individuals. Although we have not demonstrated that this mechanism is implicated directly in a causal relationship to psoriasis, it nevertheless gives further support to the possible role of the immune system in the pathogenesis of psoriasis.