Project description:<p>Healthy behavioral patterns could modulate organ functions to enhance the body’s immunity. However, whether exercise regulates antiviral innate immunity remains elusive. Here, we found that exercise promotes type-I IFN (IFN-I) production in the liver and enhances IFN-I immune activity of the body. Despite the possibility that many exercise-induced factors could regulate IFN-I production, we identified Gpld1 as a crucial molecule and the liver as the major organ to promote IFN-I production after exercise. Exercise largely loses the efficiency to induce IFN-I in Gpld1-/- mice. Further studies demonstrated that exercise-produced 3-hydroxybutanoic acid (3-HB) critically induces Gpld1 expression in the liver. Gpld1 blocks the PP2A-IRF3 interaction and therefore enhances IRF3 activation and IFN-I production, and improves the body’s antiviral ability. This study reveals that the exercise behavior improves antiviral innate immunity by linking the liver metabolism to systemic IFN-I activity, and uncovers an unknown function of liver cells in innate immunity.</p>
Project description:Previously, we reported that mice made transgenic for a picornaviral RdRP – the 3Dpol protein of Theiler’s murine encephalomyelitis virus (TMEV) – suppress infection by diverse viral families. How the picornaviral RdRP transgene exerted antiviral protection in vivo was not known. To investigate the molecular mechanism, we determined gene expression profiles in spinal cords of WT and RdRP transgenic mice prior to (baseline) and after (2 days) infection with Encephalomyocarditis Virus (EMCV).
Project description:Previously, we reported that mice made transgenic for a picornaviral RdRP – the 3Dpol protein of Theiler’s murine encephalomyelitis virus (TMEV) – suppress infection by diverse viral families. How the picornaviral RdRP transgene exerted antiviral protection in vivo was not known. To investigate the molecular mechanism, we determined gene expression profiles in spinal cords of WT and RdRP transgenic mice prior to (baseline) and after (2 days) infection with Encephalomyocarditis Virus (EMCV).
Project description:Previously, we reported that mice made transgenic for a picornaviral RdRP – the 3Dpol protein of Theiler’s murine encephalomyelitis virus (TMEV) – suppress infection by diverse viral families. How the picornaviral RdRP transgene exerted antiviral protection in vivo was not known. To investigate the molecular mechanism, we determined gene expression profiles in spinal cords of WT and RdRP transgenic mice prior to (baseline) and after (2 days) infection with Encephalomyocarditis Virus (EMCV).
Project description:Previously, we reported that mice made transgenic for a picornaviral RdRP â?? the 3Dpol protein of Theilerâ??s murine encephalomyelitis virus (TMEV) â?? suppress infection by diverse viral families. How the picornaviral RdRP transgene exerted antiviral protection in vivo was not known. To investigate the molecular mechanism, we determined gene expression profiles in spinal cords of WT and RdRP transgenic mice prior to (baseline) and after (2 days) infection with Encephalomyocarditis Virus (EMCV). Spinal cords from adult age-matched, sex-matched WT or RdRP mice were harvested prior to (baseline) viral infection. Total RNA was isolated (Qiagen RNeasy kit) and used as a template to synthesize biotinylated cRNA which was then hybridized to the HT Mouse Genome 430 2.0 GeneChip Array (Affymetrix).
Project description:Influenza defective interfering (DI) viruses have long been considered promising antiviral candidates because of their ability to interfere with replication-competent viruses and to induce antiviral immunity. However, the mechanisms underlying DI-mediated antiviral immunity have not been extensively explored. Here, we demonstrated interferon (IFN) independent protection conferred by influenza DI virus against homologous virus infection in mice deficient in type I and III IFN signaling. By integrating transcriptional and post-transcriptional regulatory data we identified unique host signatures in response to DI co-infection. DI-treated mice exhibited reduced viral transcription, less intense inflammatory and innate immune responses, and primed multiciliated cell differentiation in their lungs at an early stage of infection, even in the absence of type I or III IFNs. This increased multiciliogenesis could also be detected at the protein level by immunofluorescence staining of lung tissue from DI-treated mice. Overall, our study provides mechanistic insight into the protection mediated by DIs, implying a unifying theme involving inflammation and multiciliogenesis in maintaining respiratory homeostasis, and reveals their IFN-independent antiviral activity.
Project description:Previously, we reported that mice made transgenic for a picornaviral RdRP â the 3Dpol protein of Theilerâs murine encephalomyelitis virus (TMEV) â suppress infection by diverse viral families. How the picornaviral RdRP transgene exerted antiviral protection in vivo was not known. To investigate the molecular mechanism, we determined gene expression profiles in spinal cords of WT and RdRP transgenic mice prior to (baseline) and after (2 days) infection with Encephalomyocarditis Virus (EMCV). Spinal cords from adult age-matched WT mice were harvested prior to (baseline) viral infection and RdRP transgenic spinal cords were harvested after (2 days) infection with Encephalomyocarditis Virus (EMCV). Total RNA was isolated (Qiagen RNeasy kit) and used as a template to synthesize biotinylated cRNA which was then hybridized to the HT Mouse Genome 430 2.0 GeneChip Array (Affymetrix).
Project description:Previously, we reported that mice made transgenic for a picornaviral RdRP â the 3Dpol protein of Theilerâs murine encephalomyelitis virus (TMEV) â suppress infection by diverse viral families. How the picornaviral RdRP transgene exerted antiviral protection in vivo was not known. To investigate the molecular mechanism, we determined gene expression profiles in spinal cords of WT and RdRP transgenic mice prior to (baseline) and after (2 days) infection with Encephalomyocarditis Virus (EMCV). Spinal cords from adult age-matched, sex-matched WT mice were harvested prior to (baseline) and after (2 days post) EMCV viral infection. Total RNA was isolated (Qiagen RNeasy kit) and used as a template to synthesize biotinylated cRNA which was then hybridized to the HT Mouse Genome 430 2.0 GeneChip Array (Affymetrix).
Project description:Immune protection of the body cavities depends on the swift activation of innate and adaptive immune responses in non-classical secondary lymphoid organs known as fat-associated lymphoid clusters (FALCs). While it is well-established that fibroblastic reticular cells (FRCs) are an integral component of the immune-stimulating infrastructure of lymph nodes and other classical secondary lymphoid organs, it has remained elusive whether and how FRCs in FALCs contribute to peritoneal immunity. Using FRC-specific gene targeting, we found that FALCs are underpinned by an elaborated FRC network and that initiation of peritoneal immunity was governed through FRC activation via MyD88-dependent innate immunological sensing. FRC-specific ablation of Myd88 expression blocked recruitment of inflammatory monocytes into FALCs and subsequent CD4+ T cell-dependent B-cell activation. Moreover, containment of Salmonella infection was compromised in conditionally Myd88-deficient mice indicating that FRCs in FALCs function as initial checkpoint in the orchestration of protective immune responses in the peritoneal cavity.
Project description:Previously, we reported that mice made transgenic for a picornaviral RdRP – the 3Dpol protein of Theiler’s murine encephalomyelitis virus (TMEV) – suppress infection by diverse viruses. Using mouse genetic studies, we determined that uninfected RdRP transgenic mice inherently induce an arsenel of prominent antiviral effectors and that this phenotype is MDA5-, MAVS- and IFNαβR-dependent. To determine the mechanism underlying MDA5 activation and induction of constitutive antiviral signaling by the picornaviral RdRP, we constructed mutant RdRP transgenes. First, we introduced pervasive, coding-neutral point mutations into the RdRP cDNA to maximally disrupt primary and secondary RNA structure (RdRP∆rna). Another mutant, RdRP∆cat, lacks catalytic activity due to alanine substitution of the key catalytic center triad aspartate residues (D233, D328, and D329), but is otherwise intact at the nucleotide and amino acid levels. The WT, RdRP∆rna, and RdRP∆cat versions of the RdRP transgenes were transduced with lentiviral vectors into human THP-1 monocytes, with RdRP mRNA transcription controlled by the Spleen Focus Forming Virus (SFFV) promoter. In parallel a control cell line transduced with a vector lacking any RdRP transgene (null THP-1) was generated.
