IFNgammaR2 trafficking tunes IFNgamma-STAT1 signaling in T lymphocytes

Trends Immunol. 2006 Feb;27(2):96-101. doi: 10.1016/j.it.2005.12.002. Epub 2005 Dec 27.

Abstract

Ligand-dependent downregulation of the interferon gamma receptor signaling chain (IFNgammaR2) has always been seen as a key mechanism for shielding T lymphocytes from the antiproliferative effects of the IFNgamma-signal transducer and activator of transcription 1 (STAT1) pathway. Now, however, a ligand-independent mechanism of IFNgammaR2 internalization is emerging as a more general way of limiting IFNgamma-STAT1 signaling in T cells, with insulin-like growth factor-1 (IGF-1) and iron as the main players. Here, we review the array of immunomodulatory effects exerted by these two factors on different cell types involved in the immune response; these effects suggest that an inflammatory environment generates signals that favor IFNgammaR2 cell-surface accumulation and IFNgamma-induced apoptosis in T cells, whereas an anti-inflammatory environment promotes IFNgammaR2 internalization and induces T cell unresponsiveness to IFNgamma signaling.

Publication types

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

MeSH terms

  • Animals
  • Humans
  • Interferon gamma Receptor
  • Interferon-gamma / immunology*
  • Interferon-gamma / metabolism*
  • Protein Transport
  • Receptors, Interferon / immunology*
  • Receptors, Interferon / metabolism*
  • STAT1 Transcription Factor / metabolism*
  • Signal Transduction*
  • T-Lymphocytes / cytology
  • T-Lymphocytes / immunology
  • T-Lymphocytes / metabolism*

Substances

  • Receptors, Interferon
  • STAT1 Transcription Factor
  • Interferon-gamma