Differential regulation of interleukin-12 (IL-12)/IL-23 by Tim-3 drives T(H)17 cell development during hepatitis C virus infection

J Virol. 2013 Apr;87(8):4372-83. doi: 10.1128/JVI.03376-12. Epub 2013 Feb 6.

Abstract

Cytokine production by innate immunity is critical for shaping the adaptive immunity through regulation of T cell differentiation. In this report, we studied T cell immunoglobulin mucin domain protein 3 (Tim-3) expression on monocytes and its regulatory effect on interleukin-12 (IL-12)/IL-23 production by CD14(+) monocytes, as well as IL-17 production by CD4(+) T cells in individuals with chronic hepatitis C virus (HCV) infection. We found that Tim-3 and IL-23p19 are highly expressed and that IL-12p35 is inhibited in human CD14(+) monocytes, while IL-17 expression is upregulated in CD4(+) T cells, in chronically HCV-infected individuals compared to healthy subjects. Interestingly, Tim-3 expression is closely associated with the differential regulation of IL-12/IL-23 expression in CD14(+) monocytes and correlated to IL-17 production by CD4(+) T cells. These Tim-3-associated IL-12/IL-23/IL-17 dysregulations in HCV-infected individuals are also recapitulated in vitro by incubating healthy monocytes or peripheral blood mononuclear cells with Huh-7 hepatoma cells transfected with HCV RNA. Importantly, blocking Tim-3 signaling on monocytes restores the balance of IL-12/IL-23 through the intracellular STAT3 signaling, which in turn reverses the upregulated IL-17 expression both ex vivo and in vitro. Our findings suggest that Tim-3-mediated differential regulation of IL-12/IL-23 drives T(H)17 cell development, a milieu favoring viral persistence and autoimmune phenomenon during HCV infection.

Publication types

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

MeSH terms

  • Cell Differentiation*
  • Hepatitis A Virus Cellular Receptor 2
  • Hepatitis C, Chronic / immunology*
  • Humans
  • Interleukin-12 / biosynthesis*
  • Interleukin-23 / biosynthesis*
  • Lymphocyte Subsets / immunology
  • Lymphocyte Subsets / physiology
  • Membrane Proteins / metabolism*
  • Th17 Cells / immunology*
  • Th17 Cells / physiology

Substances

  • HAVCR2 protein, human
  • Hepatitis A Virus Cellular Receptor 2
  • Interleukin-23
  • Membrane Proteins
  • Interleukin-12