[A newly discovered chemotactic factor for neutrophil: interleukin 8]

A potent peptide chemotactic factor for leukocytes has been purified from lipopolysaccharide (LPS)-stimulated human peripheral blood mononuclear cell culture supernatant, followed by its cDNA cloning and its expression in Escherichia coli. This factor was named interleukin-8 (IL-8) since it is produced by various kinds of cells in response to inflammatory stimuli including LPS, IL-1 and tumor necrosis factor (TNF) and has pleiotropic effects on T lymphocytes and basophils as well as neutrophils. The receptors for IL-8 contain seven transmembrane domains as revealed by cDNA cloning, suggesting that they are a member of superfamily of G-protein-coupled receptors. The transcription of IL-8 gene is presumed to be regulated by the action of two kinds of transcription factors, NF-kappa B and NF-IL6, both of which are supposed to be involved in the activation of acute phase reactant genes, suggesting that the activation of IL-8 gene is a good model for elucidating the molecular mechanism of the transcription of these genes. In various kinds of diseases in which neutrophilia or neutrophil infiltration is found, the increase of IL-8 level in body fluids is often observed. The clarification of the role of IL-8 in the process of these inflammatory diseases will lead to the development of a novel kind of anti-inflammatory or immunomodulating agents.