Cytotoxic CD8+ T cell ablation enhances the capacity of regulatory T cells to delay viral elimination in Theiler's murine encephalomyelitis.

Abstract

Theiler's murine encephalomyelitis (TME) of susceptible mouse strains is a commonly used infectious animal model for multiple sclerosis. The study aim was to test the hypothesis whether cytotoxic T cell responses account for the limited impact of regulatory T cells on antiviral immunity in TME virus-induced demyelinating disease (TMEV-IDD) resistant C57BL/6 mice. TME virus-infected C57BL/6 mice were treated with (i) interleukin-2/-anti-interleukin-2-antibody-complexes to expand regulatory T cells ("Treg-expansion"), (ii) anti-CD8-antibodies to deplete cytotoxic T cells ("CD8-depletion") or (iii) with a combination of Treg-expansion and CD8-depletion ("combined treatment") prior to infection. Results showed that "combined treatment", but neither sole "Treg-expansion" nor "CD8-depletion," leads to sustained hippocampal infection and virus spread to the spinal cord in C57BL/6 mice. Prolonged infection reduces myelin basic protein expression in the spinal cord together with increased accumulation of β-amyloid precursor protein in axons, characteristic of myelin loss and axonal damage, respectively. Chronic spinal cord infection upon "combined treatment" was also associated with increased T and B cell recruitment, accumulation of CD107b+ microglia/macrophages and enhanced mRNA expression of interleukin (IL)-1α, IL-10 and tumor necrosis factor α. In conclusion, data revealed that the suppressive capacity of Treg on viral elimination is efficiently boosted by CD8-depletion, which renders C57BL/6 mice susceptible to develop chronic neuroinfection and TMEV-IDD.

• Authors: Malgorzata Ciurkiewicz, Vanessa Herder, Muhammad Akram Khan, Ann-Kathrin Uhde, René Teich, Stephan Floess, Wolfgang Baumgärtner, Jochen Huehn, Andreas Beineke
• Journal: Brain pathology (Zurich, Switzerland) (Brain Pathol) Vol. 28 Issue 3 Pg. 349-368 (05 2018) ISSN: 1750-3639 [Electronic] Switzerland
• PMID: 28452087 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)
• Copyright: © 2017 International Society of Neuropathology.

Topics

• Animals
• Brain (immunology, virology)
• CD8-Positive T-Lymphocytes (immunology)
• Cardiovirus Infections (immunology)
• Demyelinating Diseases (immunology, virology)
• Disease Models, Animal
• Female
• Mice, Inbred C57BL
• Spinal Cord (immunology, virology)
• T-Lymphocytes, Regulatory (immunology)
• Theilovirus (immunology)