Chemokines are low molecular weight inflammatory cytokines with chemoattractant properties as their major biologic effect. They are classified into at least two families. C-X-C chemokines (alpha subfamily) act primarily on neutrophils, while C-C chemokines act preferentially on monocytes. Chemokine receptors are G protein-coupled receptors that form a family of structurally and functionally related proteins. Chemokines are induced in cells and tissue in response to proinflammatory cytokines. They are produced by glomerular, tubular interstitial, and blood vessel cells. There is good evidence that chemokines contribute to neutrophil and mononuclear cell infiltration in glomeruli and interstitium. Their expression is increased in renal disease, and neutralization studies using antibodies in vivo demonstrated a role for certain chemokines in mediating renal pathology and proteinuria. Interleukin-8, RANTES, and monocyte chemotactic peptide are the best-studied chemokines in the kidney. Development of specific antibodies and receptor antagonists should help establish the precise role of these mediators in renal disease. Important therapeutic implications may result from this work.
