A novel mechanism by which interferon-gamma can regulate interleukin (IL)-13 responses. Evidence for intracellular stores of IL-13 receptor alpha -2 and their rapid mobilization by interferon-gamma

J Biol Chem. 2002 Mar 22;277(12):10387-93. doi: 10.1074/jbc.M108109200. Epub 2002 Jan 10.

Abstract

Interleukin (IL)-13 mediates its activities via a complex receptor system. Interleukin-13 receptor alpha-1 chain (IL-13Ralpha1) binds IL-13 with low affinity, but does not signal. However, when IL-13Ralpha1 combines with IL-4 receptor alpha (IL-4Ralpha), a signaling high affinity receptor complex for IL-13 is generated. In contrast, IL-13Ralpha2 alone binds IL-13 with high affinity, but does not signal and has been postulated to be a decoy receptor. Herein, we investigated the cellular localization of IL-13Ralpha2 and the regulation of its expression by confocal microscopy and flow cytometry in primary and cultured cells. Our results demonstrate that IL-13Ralpha2 is largely an intracellular molecule, which is rapidly mobilized from intracellular stores following treatment with interferon (IFN)-gamma. Up-regulation of IL-13Ralpha2 surface expression in response to IFN-gamma was rapid, did not require protein synthesis, and resulted in diminished IL-13 signaling. These results provide the first evidence that the IL-13Ralpha2 is predominantly an intracellular molecule and demonstrate a novel mechanism by which IFN-gamma can regulate IL-13 responses.

Publication types

  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amino Acid Motifs
  • Cells, Cultured
  • Dose-Response Relationship, Drug
  • Flow Cytometry
  • Gene Expression Regulation*
  • Humans
  • Interferon-gamma / metabolism*
  • Interleukin-13 / metabolism*
  • Interleukin-13 Receptor alpha1 Subunit
  • Interleukin-4 / metabolism*
  • Kinetics
  • Microscopy, Confocal
  • Monocytes / metabolism
  • Protein Binding
  • Receptors, Interleukin / metabolism*
  • Receptors, Interleukin-13
  • Signal Transduction
  • Time Factors
  • U937 Cells
  • Up-Regulation

Substances

  • IL13RA1 protein, human
  • Interleukin-13
  • Interleukin-13 Receptor alpha1 Subunit
  • Receptors, Interleukin
  • Receptors, Interleukin-13
  • Interleukin-4
  • Interferon-gamma