IL-21 as a therapeutic target in inflammatory disorders

Abstract

Introduction: IL-21, a cytokine produced by activated CD4⁺ cells, activated natural killer T cells and T helper cells in the germinal centers, is involved in the control of the function of both immune and parenchymal cells.

Areas covered: IL-21 is overproduced in many chronic inflammatory disorders, including inflammatory bowel diseases, psoriasis, rheumatoid arthritis, type I diabetes and systemic lupus erythematosus, and studies in experimental models indicate that IL-21 plays an important role in sustaining tissue-damaging immune responses in such pathologies. However, genetic deficiency of IL-21 associates with inflammatory bowel diseases and blockade of IL-21 in the early phases exacerbates the disease progression in some models of rheumatoid arthritis and systemic lupus erythematosus, thus suggesting a dual role of IL-21 in the control of immune-mediated diseases. IL-21 can exert additional protective functions for the host as it promotes cytotoxic responses against tumors and viruses.

Expert opinion: We here review the available data on the role of IL-21 in chronic inflammatory diseases and discuss the therapeutic benefit of IL-21 inhibitors in such diseases as well as the potential risks of such treatments.

Keywords::

• Crohn’s disease
• diabetes
• IL-21 receptor
• psoriasis
• rheumatoid arthritis
• systemic lupus erythematosus
• ulcerative colitis

Notes

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