Interleukin 1a, Tumor Necrosis Factor a, and Interferon ? in Psoriasis

Abstract

• Although recent studies have suggested that a variety of cytokines released by keratinocytes and inflammatory leukocytes could contribute to induction or persistence of the inflammatory processes in psoriasis, it remains unclear how production of these cytokines is regulated in psoriatic patients. To elucidate the biologic relevance of these cytokines to the pathogenesis of psoriasis, we investigated serum levels of interleukin 1α, tumor necrosis factor α, and interferon γ in 21 patients with psoriasis vulgaris, together with 21 healthy controls. The mean serum levels of interleukin 1α and tumor necrosis factor α were not significantly different from those in controls, while those of interferon γ were significantly elevated in the patients with psoriasis. Serum levels of interleukin 1α correlated negatively with clinical disease severity expressed as psoriasis area and severity index score and with duration of psoriasis. In contrast, interferon γ levels were related, although not significantly, to disease severity. In addition, an inverse correlation was noted between the interleukin 1α levels and interferon γ levels. These results indicate that interleukin 1α and interferon γ may be relevant to the induction and perpetuation, respectively, of the inflammatory responses in psoriasis, and that these cytokines, which have similar biologic properties, may strictly regulate one another's production in vivo. (Arch Dermatol.1991;127:827-830)