Differential effects of IL-21 during initiation and progression of autoimmunity against neuroantigen

J Immunol. 2005 Mar 1;174(5):2696-701. doi: 10.4049/jimmunol.174.5.2696.

Abstract

The cytokine IL-21 is closely related to IL-2 and IL-15, a cytokine family that uses the common gamma-chain for signaling. IL-21 is expressed by activated CD4(+) T cells. We examined the role of IL-21 in the autoimmune disease experimental autoimmune encephalomyelitis (EAE), an animal model for human multiple sclerosis. IL-21 administration before induction of EAE with a neuroantigen, myelin oligodendrocyte glycoprotein peptide 35-55, and adjuvant enhanced the inflammatory influx into the CNS, as well as the severity of EAE. Autoreactive T cells purified from IL-21-treated mice transferred more severe EAE than did the control encephalitogenic T cells. No such effects were observed when IL-21 was administered after EAE progressed. Additional studies demonstrated that IL-21 given before the induction of EAE boosted NK cell function, including secretion of IFN-gamma. Depletion of NK cells abrogated the effect of IL-21. Therefore, IL-21, by affecting NK cells, has differential effects during the initiation and progression of autoimmune responses against neuroantigens.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Animals
  • Autoantibodies / biosynthesis*
  • B-Lymphocyte Subsets / immunology
  • Cells, Cultured
  • Disease Progression
  • Dose-Response Relationship, Immunologic
  • Encephalomyelitis, Autoimmune, Experimental / immunology*
  • Encephalomyelitis, Autoimmune, Experimental / pathology*
  • Female
  • Glycoproteins / administration & dosage
  • Glycoproteins / immunology*
  • Immunization Schedule
  • Interferon-gamma / biosynthesis
  • Interleukin-21
  • Interleukins / administration & dosage*
  • Interleukins / antagonists & inhibitors
  • Interleukins / physiology*
  • Killer Cells, Natural / immunology
  • Lymphocyte Depletion
  • Mice
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Molecular Sequence Data
  • Myelin-Oligodendrocyte Glycoprotein
  • Peptide Fragments / administration & dosage
  • Peptide Fragments / immunology*
  • T-Lymphocyte Subsets / immunology
  • T-Lymphocyte Subsets / pathology
  • Th1 Cells / immunology

Substances

  • Autoantibodies
  • Glycoproteins
  • Interleukins
  • Myelin-Oligodendrocyte Glycoprotein
  • Peptide Fragments
  • myelin oligodendrocyte glycoprotein (35-55)
  • Interferon-gamma
  • Interleukin-21