title: Interleukin-21 as a new therapeutic target for immune-mediated diseases.
abstract: Cytokines have a decisive role in initiating and shaping pathologic responses in patients with various immune-inflammatory diseases. Recent studies indicate that interleukin (IL)-21, a cytokine produced mostly by activated CD4+ T cells, participates in the tissue damage in various tissues, owing to its ability to regulate the function of immune and non-immune cells. For instance, IL-21 controls the differentiation and functional activity of T cells, B cells and NK cells, limits the differentiation of inducible regulatory T cells (Tregs), and makes T cells resistant to the Treg-mediated immunesuppression. It also stimulates epithelial cells and fibroblasts to produce inflammatory mediators. Here, we focus on data supporting the pathogenic role of IL-21 in human inflammatory diseases and discuss pre-clinical studies that suggest that neutralization of IL-21 in vivo could be a new biological therapy to combat immune-mediated pathologies, such as inflammatory bowel diseases, diabetes, rheumatoid arthritis and systemic lupus erythematosus.
authors.affiliation: Department of Internal Medicine, University of Rome Tor Vergata, Rome 00133, Italy. gi.monteleone@med.uniroma2.it
authors.forename: Giovanni
authors.initials: G
authors.lastname: Monteleone
authors.forename: Francesco
authors.initials: F
authors.lastname: Pallone
authors.forename: Thomas T
authors.initials: TT
authors.lastname: Macdonald
mesh_terms: D000818:Animals; D001327:Autoimmune Diseases / Q000188:drug therapy / Q000503:physiopathology; D004195:Disease Models, Animal; D016503:Drug Delivery Systems; D006801:Humans; D007154:Immune System Diseases / Q000188:drug therapy* / Q000276:immunology / Q000503:physiopathology*; D007166:Immunosuppressive Agents / Q000627:therapeutic use*; D007249:Inflammation / Q000188:drug therapy* / Q000503:physiopathology; D007378:Interleukins / Q000037:antagonists & inhibitors / Q000276:immunology / Q000502:physiology*; D018448:Models, Immunological; D015398:Signal Transduction / Q000502:physiology; D000098546:Interleukin-21
chemical_list: D007166:Immunosuppressive Agents; D007378:Interleukins; D000098546:Interleukin-21