Inflammatory signals increase Fas ligand expression by inner ear cells

J Neuroimmunol. 2002 Aug;129(1-2):10-7. doi: 10.1016/s0165-5728(02)00143-1.

Abstract

There is considerable evidence that hearing and vestibular function can be influenced by immune processes. The inner ear has evolved mechanisms, such as the blood-labyrinthine barrier that limit immune responses and autoimmune processes to reduce the potential for damage to cochlear cells. Recently, expression of Fas ligand (FasL) in some non-lymphoid tissue, as in the anterior chamber of the eye, has been hypothesized to play a role in protection of sensitive organs from activated T-cells. We show that under resting conditions, cochlear cells express little or no FasL. However, after exposure to interferon-gamma in vitro, FasL is induced in many neonatal cochlear cells. In addition, we show that FasL is upregulated in adult cochlear cells after induction of a sterile labyrinthitis in vivo. The induction of FasL by inflammation may serve to limit cochlear immune responses, and to protect sensorineural tissue from immune and autoimmune damage.

Publication types

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

MeSH terms

  • Animals
  • Cells, Cultured
  • Fas Ligand Protein
  • Hair Cells, Auditory / drug effects
  • Hair Cells, Auditory / immunology*
  • Hair Cells, Auditory / metabolism
  • Immunohistochemistry
  • Interferon-gamma / immunology
  • Interferon-gamma / pharmacology
  • Labyrinthitis / immunology*
  • Labyrinthitis / metabolism
  • Labyrinthitis / physiopathology
  • Membrane Glycoproteins / immunology
  • Membrane Glycoproteins / metabolism*
  • Mice
  • Mice, Inbred CBA
  • Signal Transduction / drug effects
  • Signal Transduction / immunology
  • T-Lymphocytes / drug effects
  • T-Lymphocytes / immunology*
  • Up-Regulation / drug effects
  • Up-Regulation / immunology*
  • fas Receptor / immunology*

Substances

  • Fas Ligand Protein
  • Fasl protein, mouse
  • Membrane Glycoproteins
  • fas Receptor
  • Interferon-gamma