ABSTRACT: Induction of interferon-stimulated genes correlates with reduced growth of influenza A virus in the lungs after RIG-I agonist treatment of ferrets
Project description:The RIG-I like receptor pathway is stimulated during RNA virus infection by interaction between cytosolic RIG-I and viral RNA structures that contain short hairpin dsRNA and 5M-bM-^@M-^Y triphosphate (5M-bM-^@M-^Yppp) terminal structure. In the present study, an RNA agonist of RIG-I was synthesized in vitro and shown to stimulate RIG-I-dependent antiviral responses at concentrations in the picomolar range. In human lung epithelial A549 cells, 5M-bM-^@M-^YpppRNA specifically stimulated multiple parameters of the innate antiviral response, including IRF3, IRF7 and STAT1 activation, andinduction of inflammatory and interferon stimulated genes - hallmarks of a fully functional antiviral response. Evaluation of the magnitude and duration of gene expression by transcriptional profiling identified a robust, sustained and diversified antiviral and inflammatory response characterized by enhanced pathogen recognition and interferon (IFN)signaling. Bioinformatics analysis further identified a transcriptional signature uniquely induced by 5M-bM-^@M-^YpppRNA, and not by IFNM-NM-1-2bthat included a constellation of IRF7 and NF-kB target genes capable of mobilizing multiple arms of the innate and adaptive immune response. Treatment of primary PBMCs or lung epithelial A549 cells with 5M-bM-^@M-^YpppRNA provided significant protection against a spectrum of RNA and DNA viruses. In C57Bl/6 mice, intravenous administration of 5M-bM-^@M-^YpppRNA protected animals from a lethal challenge with H1N1 Influenza, reduced virus titers in mouse lungs and protected animals from virus-induced pneumonia. Strikingly, the RIG-I-specific transcriptional response afforded partial protection from influenza challenge, even in the absence of type I interferon signaling. This systems approach providestranscriptional, biochemical, and in vivo analysis of the antiviral efficacy of 5M-bM-^@M-^YpppRNA and highlights the therapeutic potential associated with the use of RIG-I agonists as broad spectrum antiviral agents. Kinetic analysis of A549 cells treated with 5'pppRNA and analyzed at 1h, 2h, 4h, 6h, 8h, 12h, 24h or 48h.
Project description:The RIG-I like receptor pathway is stimulated during RNA virus infection by interaction between cytosolic RIG-I and viral RNA structures that contain short hairpin dsRNA and 5M-bM-^@M-^Y triphosphate (5M-bM-^@M-^Yppp) terminal structure. In the present study, an RNA agonist of RIG-I was synthesized in vitro and shown to stimulate RIG-I-dependent antiviral responses at concentrations in the picomolar range. In human lung epithelial A549 cells, 5M-bM-^@M-^YpppRNA specifically stimulated multiple parameters of the innate antiviral response, including IRF3, IRF7 and STAT1 activation, andinduction of inflammatory and interferon stimulated genes - hallmarks of a fully functional antiviral response. Evaluation of the magnitude and duration of gene expression by transcriptional profiling identified a robust, sustained and diversified antiviral and inflammatory response characterized by enhanced pathogen recognition and interferon (IFN)signaling. Bioinformatics analysis further identified a transcriptional signature uniquely induced by 5M-bM-^@M-^YpppRNA, and not by IFNM-NM-1-2bthat included a constellation of IRF7 and NF-kB target genes capable of mobilizing multiple arms of the innate and adaptive immune response. Treatment of primary PBMCs or lung epithelial A549 cells with 5M-bM-^@M-^YpppRNA provided significant protection against a spectrum of RNA and DNA viruses. In C57Bl/6 mice, intravenous administration of 5M-bM-^@M-^YpppRNA protected animals from a lethal challenge with H1N1 Influenza, reduced virus titers in mouse lungs and protected animals from virus-induced pneumonia. Strikingly, the RIG-I-specific transcriptional response afforded partial protection from influenza challenge, even in the absence of type I interferon signaling. This systems approach providestranscriptional, biochemical, and in vivo analysis of the antiviral efficacy of 5M-bM-^@M-^YpppRNA and highlights the therapeutic potential associated with the use of RIG-I agonists as broad spectrum antiviral agents. A549 cells were either non-treated, treated with RNAiMax only, transfected with 5'pppRNA, or treated with IFNa-2b and analysed at 6h or 24h.
Project description:Many patients who are diagnosed with coronavirus disease 2019 (COVID-19) suffer from venous thromboembolic complications despite the use of stringent anticoagulant prophylaxis. Studies on the exact mechanism(s) underlying thrombosis in COVID-19 are limited as animal models commonly used to study venous thrombosis pathophysiology (i.e. rats and mice) are naturally not susceptible to Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2). Ferrets are susceptible to SARS-CoV-2 infection, successfully used to study virus transmission, and were previously used to study activation of coagulation and thrombosis during influenza virus infection. Here, we used plasma and lung material from SARS-CoV-2-inoculated ferrets to explore their use in studying COVID-19-associated changes in coagulation and thrombosis. Lungs of ferrets inoculated intranasally with SARS-CoV-2 demonstrated alveolar septa that were mildly expanded by macrophages, and diffuse interstitial histiocytic pneumonia. However, no macroscopical or microscopical evidence of vascular thrombosis in the lungs of SARS-CoV-2-inoculated ferrets was found. Longitudinal plasma profiling using a mass spectrometry-based approach revealed minor differences in plasma protein profiles in SARS-CoV-2-inoculated ferrets up to 2 weeks post-infection. Apart from fibrinogen, the majority of plasma coagulation factors were stable and demonstrated a low coefficient of variation. We conclude that while ferrets are an essential and well-suited animal model to study SARS-CoV-2 transmission, their use to study SARS-CoV-2-related changes relevant to thrombotic disease is limited.
Project description:The RIG-I like receptor pathway is stimulated during RNA virus infection by interaction between cytosolic RIG-I and viral RNA structures that contain short hairpin dsRNA and 5’ triphosphate (5’ppp) terminal structure. In the present study, an RNA agonist of RIG-I was synthesized in vitro and shown to stimulate RIG-I-dependent antiviral responses at concentrations in the picomolar range. In human lung epithelial A549 cells, 5’pppRNA specifically stimulated multiple parameters of the innate antiviral response, including IRF3, IRF7 and STAT1 activation, andinduction of inflammatory and interferon stimulated genes - hallmarks of a fully functional antiviral response. Evaluation of the magnitude and duration of gene expression by transcriptional profiling identified a robust, sustained and diversified antiviral and inflammatory response characterized by enhanced pathogen recognition and interferon (IFN)signaling. Bioinformatics analysis further identified a transcriptional signature uniquely induced by 5’pppRNA, and not by IFNα-2bthat included a constellation of IRF7 and NF-kB target genes capable of mobilizing multiple arms of the innate and adaptive immune response. Treatment of primary PBMCs or lung epithelial A549 cells with 5’pppRNA provided significant protection against a spectrum of RNA and DNA viruses. In C57Bl/6 mice, intravenous administration of 5’pppRNA protected animals from a lethal challenge with H1N1 Influenza, reduced virus titers in mouse lungs and protected animals from virus-induced pneumonia. Strikingly, the RIG-I-specific transcriptional response afforded partial protection from influenza challenge, even in the absence of type I interferon signaling. This systems approach providestranscriptional, biochemical, and in vivo analysis of the antiviral efficacy of 5’pppRNA and highlights the therapeutic potential associated with the use of RIG-I agonists as broad spectrum antiviral agents.
Project description:The RIG-I like receptor pathway is stimulated during RNA virus infection by interaction between cytosolic RIG-I and viral RNA structures that contain short hairpin dsRNA and 5’ triphosphate (5’ppp) terminal structure. In the present study, an RNA agonist of RIG-I was synthesized in vitro and shown to stimulate RIG-I-dependent antiviral responses at concentrations in the picomolar range. In human lung epithelial A549 cells, 5’pppRNA specifically stimulated multiple parameters of the innate antiviral response, including IRF3, IRF7 and STAT1 activation, andinduction of inflammatory and interferon stimulated genes - hallmarks of a fully functional antiviral response. Evaluation of the magnitude and duration of gene expression by transcriptional profiling identified a robust, sustained and diversified antiviral and inflammatory response characterized by enhanced pathogen recognition and interferon (IFN)signaling. Bioinformatics analysis further identified a transcriptional signature uniquely induced by 5’pppRNA, and not by IFNα-2bthat included a constellation of IRF7 and NF-kB target genes capable of mobilizing multiple arms of the innate and adaptive immune response. Treatment of primary PBMCs or lung epithelial A549 cells with 5’pppRNA provided significant protection against a spectrum of RNA and DNA viruses. In C57Bl/6 mice, intravenous administration of 5’pppRNA protected animals from a lethal challenge with H1N1 Influenza, reduced virus titers in mouse lungs and protected animals from virus-induced pneumonia. Strikingly, the RIG-I-specific transcriptional response afforded partial protection from influenza challenge, even in the absence of type I interferon signaling. This systems approach providestranscriptional, biochemical, and in vivo analysis of the antiviral efficacy of 5’pppRNA and highlights the therapeutic potential associated with the use of RIG-I agonists as broad spectrum antiviral agents.
Project description:Severe fever with thrombocytopenia syndrome phlebovirus (SFTSV), listed in the WHO most dangerous pathogens, has 12-30% fatality rates with a characteristic thrombocytopenia syndrome. With a majority of clinically diagnosed SFTSV patients older than ~50 years, age is a critical risk factor for SFTSV morbidity and mortality. Here, we report an age-dependent ferret model of SFTSV infection and pathogenesis that fully recapitulates the clinical manifestations of human infections. While young adult ferrets (≤2 years old) did not show any clinical symptoms and mortality, SFTSV-infected aged ferrets (≥4 years old) demonstrated severe thrombocytopenia, reduced white blood cells, and high fever with 93% mortality rate. Moreover, significantly higher viral load was observed in aged ferrets. Transcriptome analysis of SFTSV-infected young ferrets revealed strong interferon-mediated anti-viral signaling, whereas inflammatory immune responses were markedly upregulated and persisted in aged ferrets. Thus, this immunocompetent age-dependent ferret model should be useful for anti-SFTSV therapy and vaccine development.
Project description:Influenza A viruses (IAVs) present major public health threats from annual seasonal epidemics and pandemics as well as from viruses adapted to a variety of animals including poultry, pigs, and horses. Vaccines that broadly protect against all such IAVs, so-called “universal” influenza vaccines, do not currently exist, but are urgently needed. Here, we demonstrated that an inactivated, multivalent whole virus vaccine, delivered intramuscularly or intranasally, was broadly protective against challenges with multiple IAV hemagglutinin and neuraminidase subtypes in both mice and ferrets. The vaccine is comprised of four beta-propiolactone-inactivated low pathogenicity avian influenza A virus subtypes of H1N9, H3N8, H5N1, or H7N3. Vaccinated mice and ferrets demonstrated substantial protection against a variety of IAVs, including the 1918 H1N1 strain, the highly pathogenic avian H5N8 strain, and H7N9. We also observed protection against challenge with antigenically variable and heterosubtypic avian, swine, and human viruses. Compared to mock vaccinated animals, vaccinated mice and ferrets demonstrated marked reductions in viral titers, lung pathology, and host inflammatory responses. This vaccine approach indicates the feasibility of eliciting broad, heterosubtypic IAV protection and identifies a promising candidate for influenza vaccine clinical development.
Project description:Proteomics data from lungs and trachea of ferrets (Mustela putorius furo) infected intranasally with either influenza A/California/04/2009 (CA04) virus or influenza A/Brevig Mission/1/1918 (1918) virus. Sections of trachea and lung collected were at 1, 3 and 8 days post-infection.
Project description:Influenza virus transmission between mothers and nursing-infants has not been investigated although mothers and infants often develop severe disease. Ferrets are considered the most appropriate model for influenza studies. We investigated influenza transmission in infant and nursing-mother ferrets. Influenza infected infants transmitted virus to mother mammary glands leading to live virus excretion in milk and influenza virus positive mammary gland epithelial cells. Global gene expression analysis showed down-regulation of milk production and induction of breast involution and oncogenesis pathways. Our results provide insight into influenza transmission between mothers and infants which may impact fields of infectious disease, maternal/infant health and neoplasm etiology. Total RNA was obtained from ferret lungs at days 3 and 6 post-intranasal infection with 10^5 EID50 A/California/07/2009 (H1N1) (n = 3/time-point). Total RNA was also collected from uninfected control lung tissues (n = 3). Changes in gene expression relative to uninfected tissue controls were then investigated.
Project description:We identified a small molecule compound, KIN1148, that directly binds RIG-I to drive IRF3 and NF B activation and expression of innate immune genes, cytokines and chemokines. KIN1148 activates RIG-I in an RNA- and ATP-independent manner and does not induce a canonical antiviral interferon (IFN) gene program traditionally associated with RIG-I activation. When administered in combination with a vaccine against influenza A virus (IAV), KIN1148 induces both neutralizing antibody and broadly cross-protective IAV-specific T cell responses compared to vaccination alone, which induces poor responses. In this study, we demonstrate that KIN1148 directly engages RIG-I to activate IRF3- and NFB-dependent innate immune responses, making it the first small molecule RIG-I agonist to be identified. Biochemical studies show that KIN1148 binds to RIG-I to drive RIG-I self-oligomerization and downstream signaling activation in an RNA- and ATP-independent manner. We further find that transcriptional programs induced by KIN1148 treatment exhibit shared and unique signatures to that induced by other methods of RIG-I activation, including Sendai virus (SeV) infection and PAMP RNA transfection. KIN1148 adjuvants a split virus (SV) vaccine at suboptimal dose to protect mice from lethal challenge with a recombinant highly pathogenic avian H5N1 influenza virus, A/Vietnam/1203/2004.