Dataset Information

The roles of IRF-3 and IRF-7 in innate antiviral immunity against dengue virus

ABSTRACT: We investigated the roles of IRF-3 and IRF-7 in innate antiviral immunity against dengue virus (DENV). Double-deficient Irf-3-/-7-/- mice infected with the DENV2 strain S221 possessed 1,000-150,000 fold higher levels of viral RNA than wild-type and single-deficient mice 24 hours after infection; however, they remained resistant to lethal infection. IFN-α/β was induced similarly in wild-type and Irf-3-/- mice post DENV infection, whereas in the Irf-7-/- and Irf-3-/-7-/- mice, significantly low levels of IFN-α/β expression was observed within 24 hours post-infection. IFN-stimulated gene (ISG) induction was also delayed in Irf-3-/-7-/- mice relative to wild-type and single-deficient mice. In particular, Cxcl10 and Ifnα2 were rapidly induced independently of both IRF-3 and IRF-7 in the Irf-3-/-7-/- mice with DENV infection. Higher levels of serum IFN-γ, IL-6, CXCL10, IL-8, IL-12 p70, and TNF were also observed in Irf-3-/-7-/- mice 24 hours after infection, at which time point viral titers peaked and started to be cleared. Antibody-mediated blockade experiments revealed that IFN-γ, CXCL10, and CXCR3 function to restrict DENV replication in Irf-3-/-7-/- mice. Additionally, the ISGs Cxcl10, Ifit1, Ifit3, and Mx2 can be induced via an IRF-3- and IRF-7-independent pathway that does not involve IFN-γ signaling for protection against DENV. Collectively, these results demonstrate that IRF-3 and IRF-7 are redundant, albeit IRF-7 plays a more important role than IRF-3 in inducing the initial IFN-α/β response; only the combined actions of IRF-3 and IRF-7 are necessary for efficient control of early DENV infection; and the late, IRF-3- and IRF-7-independent pathway contributes to anti-DENV immunity.

ORGANISM(S): Mus musculus

PROVIDER: GSE49871 | GEO | 2013/08/15

SECONDARY ACCESSION(S): PRJNA215223

REPOSITORIES: GEO

ACCESS DATA

Similar Datasets

Project description:We investigated the roles of IRF-3 and IRF-7 in innate antiviral immunity against dengue virus (DENV). Double-deficient Irf-3-/-7-/- mice infected with the DENV2 strain S221 possessed 1,000-150,000 fold higher levels of viral RNA than wild-type and single-deficient mice 24 hours after infection; however, they remained resistant to lethal infection. IFN-α/β was induced similarly in wild-type and Irf-3-/- mice post DENV infection, whereas in the Irf-7-/- and Irf-3-/-7-/- mice, significantly low levels of IFN-α/β expression was observed within 24 hours post-infection. IFN-stimulated gene (ISG) induction was also delayed in Irf-3-/-7-/- mice relative to wild-type and single-deficient mice. In particular, Cxcl10 and Ifnα2 were rapidly induced independently of both IRF-3 and IRF-7 in the Irf-3-/-7-/- mice with DENV infection. Higher levels of serum IFN-γ, IL-6, CXCL10, IL-8, IL-12 p70, and TNF were also observed in Irf-3-/-7-/- mice 24 hours after infection, at which time point viral titers peaked and started to be cleared. Antibody-mediated blockade experiments revealed that IFN-γ, CXCL10, and CXCR3 function to restrict DENV replication in Irf-3-/-7-/- mice. Additionally, the ISGs Cxcl10, Ifit1, Ifit3, and Mx2 can be induced via an IRF-3- and IRF-7-independent pathway that does not involve IFN-γ signaling for protection against DENV. Collectively, these results demonstrate that IRF-3 and IRF-7 are redundant, albeit IRF-7 plays a more important role than IRF-3 in inducing the initial IFN-α/β response; only the combined actions of IRF-3 and IRF-7 are necessary for efficient control of early DENV infection; and the late, IRF-3- and IRF-7-independent pathway contributes to anti-DENV immunity. To identify the antiviral genes that are controlled by IRF-3 and IRF-7 signaling during DENV infection, we examined a panel of ISG expression in the spleens of wild-type, Irf-3-/-, Irf-7-/- and Irf-3-/-7-/- mice at 12 or 24 hours after DENV infection using a quantitative PCR array kit. The fold changes in expression of 55 genes from infected mice were normalized to that of strain-matched naïve mice.

Project description:Dengue virus (DENV) infection is associated with a range of clinical manifestations, from self-limiting dengue fever (DF) to life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Although DENV-specific CD4 T cells are capable of producing inflammatory cytokines and can acquire cytotoxic functions in previously DENV-exposed individuals, much less is known related to DENV-specific CD4 T cells during acute DENV infection and disease. In this study, we set out to characterize the immune signatures of DENV-specific CD4 T cells during acute infection and investigate whether DENV-specific CD4 T cell response differs between DF and DHF. Previous studies suggest that increased IL-10 level in the blood is associated with severe dengue disease. Here we show evidence of DENV-specific IL-10-producing CD4 T cells during acute DENV infection. More specifically, an IL-10+IFN-γ+ double positive (DP) CD4 T cell population was prominent in acute hospitalized DENV cases but disappeared at the convalescent stage. RNA-sequencing analysis revealed that these cells were associated with gene signatures that marginally overlapped with previously identified signatures of cytotoxic CD4 T cells and type 1 regulatory T (Tr1)-like cells. However, the majority of the genes differentially expressed by DP cells were not related to cytotoxic CD4 T cells or Tr1-like cells. These genes include IL-21, IL-22, CD86, CD109, and CCR1, which are involved in T cell activation, function, cytokine signaling, and migration. Notably, the magnitude of DP cell response was higher in DHF than DF, whereas the gene expression profile of DP cells was similar between DF and DHF. Finally, our data show that DENV-specific DP cells are largely homogeneous based on the expression of 31 selected markers. Overall, this study reveals unique phenotypes of virus-specific IL-10/IFN-γ co-producing CD4 cells and indicates that the quantity but not quality of these cells may be positively correlated with dengue disease severity.

Dataset Information

The roles of IRF-3 and IRF-7 in innate antiviral immunity against dengue virus

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure