Extrinsically derived TNF is primarily responsible for limiting antiviral CD8+ T cell response magnitude

PLoS One. 2017 Sep 8;12(9):e0184732. doi: 10.1371/journal.pone.0184732. eCollection 2017.

Abstract

TNF is a pro-inflammatory cytokine produced by both lymphoid and non-lymphoid cells. As a consequence of the widespread expression of its receptors (TNFR1 and 2), TNF plays a role in many important biological processes. In the context of influenza A virus (IAV) infection, TNF has variably been implicated in mediating immunopathology as well as suppression of the immune response. Although a number of cell types are able to produce TNF, the ability of CD8+ T cells to produce TNF following viral infection is a hallmark of their effector function. As such, the regulation and role of CD8+ T cell-derived TNF following viral infection is of great interest. Here, we show that the biphasic production of TNF by CD8+ T cells following in vitro stimulation corresponds to distinct patterns of epigenetic modifications. Further, we show that a global loss of TNF during IAV infection results in an augmentation of the peripheral virus-specific CD8+ T cell response. Subsequent adoptive transfer experiments demonstrated that this attenuation of the CD8+ T cell response was largely, but not exclusively, conferred by extrinsic TNF, with intrinsically-derived TNF making only modest contributions. In conclusion, TNF exerts an immunoregulatory role on CD8+ T cell responses following IAV infection, an effect that is largely mediated by extrinsically-derived TNF.

MeSH terms

  • Animals
  • CD8-Positive T-Lymphocytes / metabolism*
  • Chromatin Immunoprecipitation
  • Female
  • Influenza A virus / pathogenicity
  • Mice
  • Mice, Inbred C57BL
  • RNA Polymerase II / metabolism
  • Receptors, Tumor Necrosis Factor / metabolism*
  • Receptors, Tumor Necrosis Factor, Type I / metabolism
  • Receptors, Tumor Necrosis Factor, Type II / metabolism

Substances

  • Receptors, Tumor Necrosis Factor
  • Receptors, Tumor Necrosis Factor, Type I
  • Receptors, Tumor Necrosis Factor, Type II
  • RNA Polymerase II

Grants and funding

This work was supported by Australian National Health and Medical Research Council (NHMRC) funding (APP1071916). and a Sylvia and Charles Viertel Senior Medical Research Fellowship awarded to N.L.L.G.