β-arrestin 2 inhibits proinflammatory chemokine production and attenuates contact allergic inflammation in the skin

J Invest Dermatol. 2014 Aug;134(8):2131-2137. doi: 10.1038/jid.2014.117. Epub 2014 Feb 27.

Abstract

β-Arrestins participate in G-protein receptor signaling and act as adapter proteins that direct the recruitment, activation, and scaffolding of various cytoplasmic signaling complexes. β-Arrestin 2-deficient (Arrb2(-/-)) mice show decreased T-cell recruitment into allergic lung tissue but increased neutrophil infiltration into wounded skin. Given these opposing effects in different immune cell subsets, we investigated the role of β-arrestin 2 in the regulation of contact hypersensitivity responses. We observed significantly increased allergic ear swelling to the obligate contact sensitizers DNFB and FITC in Arrb2(-/-) compared with wild-type mice. Immunohistological analyses revealed strikingly increased neutrophil infiltration with abundant subcorneal pustules in inflamed ear tissue of DNFB-allergic Arrb2(-/-) mice. Experiments involving adoptive transfers of sensitized lymphocytes and bone marrow chimeric mice indicated that β-arrestin 2 exerts its anti-inflammatory effects predominantly through radioresistant, skin-resident cells in the challenge phase of contact hypersensitivity. As a potential mechanism, we found that primary cultures of β-arrestin 2-deficient keratinocytes secreted higher levels of neutrophil-attracting chemokines including CXCL1/KC in response to T cell-derived cytokines in vitro. These experimental results support a model in which β-arrestin 2 inhibits the production of proinflammatory chemokines, which limits the recruitment of myeloid immune cells and thereby attenuates allergic skin inflammation.

MeSH terms

  • Animals
  • Arrestins / physiology*
  • Chemokine CXCL2 / biosynthesis
  • Chemokines / biosynthesis*
  • Dermatitis, Allergic Contact / immunology*
  • Dermatitis, Allergic Contact / prevention & control
  • Dinitrofluorobenzene
  • Keratinocytes / immunology
  • Mice
  • Mice, Inbred C57BL
  • Neutrophils / physiology
  • Radiation Tolerance
  • beta-Arrestin 2
  • beta-Arrestins

Substances

  • Arrb2 protein, mouse
  • Arrestins
  • Chemokine CXCL2
  • Chemokines
  • Cxcl2 protein, mouse
  • beta-Arrestin 2
  • beta-Arrestins
  • Dinitrofluorobenzene