Role of interleukin-8 receptor in skin.

Interleukin-8 (IL-8) is a potent chemotactic and proinflammatory cytokine, produced in the skin by a variety of cells in response to inflammatory stimuli. Recent studies suggest that in addition to its potent actions on leukocytes, IL-8 exerts a direct influence on several functions of human epidermal cells such as chemotaxis, Candida albicans killing activity or proliferation. The effects of IL-8 are mediated by binding to two types of specific high-affinity receptors which contain seven transmembrane domains typical of guanine nucleotide binding protein (G protein)-coupled receptors. In the skin, a broad spectrum of cells such as neutrophils, T lymphocytes, mast cells, dermal macrophages, endothelial cells and keratinocytes possess binding sites for IL-8. Recently, increased expression of epidermal IL-8 receptors has been observed in psoriasis an inflammatory and hyperproliferative skin disease. Since the effects of IL-8 may be modulated at the receptor level, the pharmacological manipulation of the IL-8 receptor may prove an important target for the therapy of skin diseases with increased IL-8 levels.