Biology of IL-21 and the IL-21 receptor

Immunol Rev. 2004 Dec;202:84-95. doi: 10.1111/j.0105-2896.2004.00201.x.

Abstract

Interleukin-21 (IL-21) is the newest member of the common gamma-chain family of cytokines, which includes IL-2, IL-4, IL-7, IL-9, IL-13, and IL-15. Its private receptor, IL-21R, has been shown to activate the Janus kinase/signal transducers and activators of transcription signaling pathway upon ligand binding. Initial studies have demonstrated that IL-21 has pleiotropic effects on the proliferation, differentiation, and effector functions of B, T, natural killer, and dendritic cells. More recently, the potential therapeutic capacity of IL-21 in the treatment of cancers has been widely investigated. The biological role of IL-21 in the immune system is complex, as IL-21 has been shown to have the ability to both promote and inhibit immune responses. Overall, the current data point to IL-21 being a novel immunomodulatory cytokine, whose regulation of any given immune response is highly dependent on the surrounding environmental context.

Publication types

  • Review

MeSH terms

  • Animals
  • B-Lymphocytes / physiology
  • Dendritic Cells / physiology
  • Humans
  • Interleukin-21 Receptor alpha Subunit
  • Interleukins / genetics
  • Interleukins / physiology*
  • Killer Cells, Natural / physiology
  • Mice
  • Receptors, Interleukin / genetics
  • Receptors, Interleukin / physiology*
  • Receptors, Interleukin-21
  • Signal Transduction / physiology
  • T-Lymphocytes / physiology

Substances

  • IL21R protein, human
  • Il21r protein, mouse
  • Interleukin-21 Receptor alpha Subunit
  • Interleukins
  • Receptors, Interleukin
  • Receptors, Interleukin-21
  • interleukin-21