MPYS/STING-mediated TNF-α, not type I IFN, is essential for the mucosal adjuvant activity of (3'-5')-cyclic-di-guanosine-monophosphate in vivo

J Immunol. 2014 Jan 1;192(1):492-502. doi: 10.4049/jimmunol.1301812. Epub 2013 Dec 4.


The bacterial second messenger (3'-5')-cyclic-di-guanosine-monophosphate (CDG) is a promising mucosal adjuvant candidate that activates balanced Th1/Th2/Th17 responses. We showed previously that CDG activates stimulator of IFN genes (STING)-dependent IFN-I production in vitro. However, it is unknown whether STING or IFN-I is required for the CDG adjuvant activity in vivo. In this study, we show that STING(-/-) mice (Tmem173(<tm1Camb>)) do not produce Ag-specific Abs or Th1/Th2/Th17 cytokines during CDG/Ag immunization. Intranasal administration of CDG did not induce TNF-α, IL-1β, IL-6, IL-12, or MCP-1 production in STING(-/-) mice. Surprisingly, we found that the cytokine and Ab responses were unaltered in CDG/Ag-immunized IFNAR(-/-) mice. Instead, we found that CDG activates STING-dependent, IFN-I-independent TNF-α production in vivo and in vitro. Furthermore, using a TNFR1(-/-) mouse, we demonstrate that TNF-α signaling is critical for CDG-induced Ag-specific Ab and Th1/Th2 cytokine production. This is distinct from STING-mediated DNA adjuvant activity, which requires IFN-I, but not TNF-α, production. Finally, we found that CDG activates STING-dependent, but IRF3 stimulation-independent, NF-κB signaling. Our results established an essential role for STING-mediated TNF-α production in the mucosal adjuvant activity of CDG in vivo and revealed a novel IFN-I stimulation-independent STING-NF-κB-TNF-α pathway.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adjuvants, Immunologic
  • Animals
  • Chemokines / biosynthesis
  • Cyclic GMP / analogs & derivatives*
  • Cyclic GMP / immunology
  • Cytokines / biosynthesis
  • Dendritic Cells / immunology
  • Dendritic Cells / metabolism
  • Female
  • Immunoglobulin G / immunology
  • Interferon Regulatory Factor-3 / metabolism
  • Interferon Type I / metabolism
  • Membrane Proteins / metabolism*
  • Mice
  • Mucous Membrane / immunology*
  • Mucous Membrane / metabolism*
  • NF-kappa B / metabolism
  • Ovalbumin / immunology
  • Signal Transduction
  • Tumor Necrosis Factor-alpha / metabolism*


  • Adjuvants, Immunologic
  • Chemokines
  • Cytokines
  • Immunoglobulin G
  • Interferon Regulatory Factor-3
  • Interferon Type I
  • Membrane Proteins
  • NF-kappa B
  • Sting1 protein, mouse
  • Tumor Necrosis Factor-alpha
  • bis(3',5')-cyclic diguanylic acid
  • Ovalbumin
  • Cyclic GMP