Sustained TNF production by central nervous system infiltrating macrophages promotes progressive autoimmune

Alice Valentin-Torres1, Carine Savarin2, David R Hinton3

  • 1Department of Neurosciences NC-30, Lerner Research Institute, The Cleveland Clinic, 9500 Euclid Ave., Cleveland, OH, 44195, USA. valenta@ccf.org.

Abstract

Insights

Targeting tumor necrosis factor (TNF) in experimental autoimmune encephalomyelitis (EAE) reduced disability and mortality. This study shows sustained TNF exacerbates central nervous system (CNS) inflammation and damage in progressive EAE.

Area of Science:

  • Neuroimmunology
  • Autoimmune Diseases

Background:

  • Tumor necrosis factor (TNF) plays a role in multiple sclerosis (MS) and its model, experimental autoimmune encephalomyelitis (EAE).
  • The precise role of TNF in progressive MS and EAE remains unclear.
  • This study investigates TNF's role in exacerbating CNS pathology and inflammation in a progressive EAE model.

Purpose of the Study:

  • To evaluate the role of sustained TNF in exacerbating central nervous system (CNS) pathology and inflammation during progressive EAE.
  • To assess the therapeutic effects of anti-TNF treatment on disability, demyelination, CNS inflammation, and blood-brain barrier (BBB) permeability.

Main Methods:

  • A progressive EAE model was established using myelin oligodendrocyte glycoprotein (MOG) peptide immunization in GFAPγR1∆ mice.
  • Mice were treated with anti-TNF or control monoclonal antibody during acute disease.
  • Therapeutic effects were monitored for clinical disability, demyelination, CNS inflammation, and BBB permeability.

Main Results:

  • TNF was sustained in infiltrating macrophages.
  • Anti-TNF treatment significantly decreased clinical disability and mortality within 7 days.
  • TNF neutralization reduced myelin loss, leukocyte infiltration, macrophage activation, mitigated CNS inflammation, restored BBB integrity, and enhanced CNS anti-inflammatory responses.

Conclusions:

  • Sustained TNF production by macrophages in progressive EAE worsens disease severity.
  • TNF exacerbates disease by promoting inflammation and disrupting BBB integrity.
  • Neutralizing TNF counteracts these effects, promoting an anti-inflammatory environment necessary for disease remission.