ABSTRACT
Coronaviruses (CoVs) are RNA viruses that can infect a wide range of animals, including humans, and cause severe respiratory and gastrointestinal disease. The Gammacoronavirus avian infectious bronchitis virus (IBV) causes acute and contagious diseases in chickens, leading to severe economic losses. Nonstructural protein 14 (Nsp14) is a nonstructural protein encoded by the CoV genome. This protein has a regulatory role in viral virulence and replication. However, the function and mechanism of IBV Nsp14 in regulating the host's innate immune response remain unclear. Here we report that IBV Nsp14 was a JAK-STAT signaling pathway antagonist in chicken macrophage (HD11) cells. In these cells, Nsp14 protein overexpression blocked IBV suppression induced by exogenous chIFN-γ treatment. Meanwhile, Nsp14 remarkably reduced interferon-gamma-activated sequence (GAS) promoter activation and chIFN-γ-induced interferon-stimulated gene expression. Nsp14 impaired the nuclear translocation of chSTAT1. Furthermore, Nsp14 interacted with Janus kinase 1 (JAK1) to degrade JAK1 via the autophagy pathway, thereby preventing the activation of the JAK-STAT signaling pathway and facilitating viral replication. These results indicated a novel mechanism by which IBV inhibits the host antiviral response and provide new insights into the selection of antiviral targets against CoV.
Subject(s)
Infectious bronchitis virus , Animals , Antiviral Agents/pharmacology , Chickens , Infectious bronchitis virus/physiology , Janus Kinase 1/genetics , Signal TransductionABSTRACT
Autoinflammatory disease can result from monogenic errors of immunity. We describe a patient with early-onset multi-organ immune dysregulation resulting from a mosaic, gain-of-function mutation (S703I) in JAK1, encoding a kinase essential for signaling downstream of >25 cytokines. By custom single-cell RNA sequencing, we examine mosaicism with single-cell resolution. We find that JAK1 transcription was predominantly restricted to a single allele across different cells, introducing the concept of a mutational "transcriptotype" that differs from the genotype. Functionally, the mutation increases JAK1 activity and transactivates partnering JAKs, independent of its catalytic domain. S703I JAK1 is not only hypermorphic for cytokine signaling but also neomorphic, as it enables signaling cascades not canonically mediated by JAK1. Given these results, the patient was treated with tofacitinib, a JAK inhibitor, leading to the rapid resolution of clinical disease. These findings offer a platform for personalized medicine with the concurrent discovery of fundamental biological principles.
Subject(s)
Hereditary Autoinflammatory Diseases/genetics , Hereditary Autoinflammatory Diseases/pathology , Janus Kinase 1/genetics , Systemic Inflammatory Response Syndrome/genetics , Systemic Inflammatory Response Syndrome/pathology , Adolescent , COVID-19/mortality , Catalytic Domain/genetics , Cell Line , Cytokines/metabolism , Female , Gain of Function Mutation/genetics , Genotype , HEK293 Cells , Hereditary Autoinflammatory Diseases/drug therapy , Humans , Janus Kinase 1/antagonists & inhibitors , Mosaicism , Piperidines/therapeutic use , Precision Medicine/methods , Pyrimidines/therapeutic use , Signal Transduction/immunology , Systemic Inflammatory Response Syndrome/drug therapySubject(s)
Azetidines/therapeutic use , Betacoronavirus/pathogenicity , Coronavirus Infections/drug therapy , Interferon-alpha/therapeutic use , Interferon-beta/therapeutic use , Interferons/therapeutic use , Pneumonia, Viral/drug therapy , Sulfonamides/therapeutic use , Betacoronavirus/immunology , COVID-19 , Coronavirus Infections/immunology , Coronavirus Infections/pathology , Coronavirus Infections/virology , Gene Expression Regulation , Humans , Immunity, Cellular/drug effects , Immunity, Humoral/drug effects , Interferon Regulatory Factors/genetics , Interferon Regulatory Factors/immunology , Interferon-alpha/genetics , Interferon-alpha/immunology , Interferon-beta/genetics , Interferon-beta/immunology , Interferons/genetics , Interferons/immunology , Interleukin-1/genetics , Interleukin-1/immunology , Interleukin-6/antagonists & inhibitors , Interleukin-6/genetics , Interleukin-6/immunology , Janus Kinase 1/antagonists & inhibitors , Janus Kinase 1/genetics , Janus Kinase 1/immunology , Lung/drug effects , Lung/immunology , Lung/pathology , Pandemics , Pneumonia, Viral/immunology , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , Purines , Pyrazoles , SARS-CoV-2 , Severity of Illness Index , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/immunologyABSTRACT
Approximately 15% of patients with coronavirus disease 2019 (COVID-19) experience severe disease, and 5% progress to critical stage that can result in rapid death. No vaccines or antiviral treatments have yet proven effective against COVID-19. Patients with severe COVID-19 experience elevated plasma levels of pro-inflammatory cytokines, which can result in cytokine storm, followed by massive immune cell infiltration into the lungs leading to alveolar damage, decreased lung function, and rapid progression to death. As many of the elevated cytokines signal through Janus kinase (JAK)1/JAK2, inhibition of these pathways with ruxolitinib has the potential to mitigate the COVID-19-associated cytokine storm and reduce mortality. This is supported by preclinical and clinical data from other diseases with hyperinflammatory states, where ruxolitinib has been shown to reduce cytokine levels and improve outcomes. The urgent need for treatments for patients with severe disease support expedited investigation of ruxolitinib for patients with COVID-19.
Subject(s)
Betacoronavirus/pathogenicity , Coronavirus Infections/drug therapy , Cytokine Release Syndrome/prevention & control , Cytokines/antagonists & inhibitors , Pneumonia, Viral/drug therapy , Protein Kinase Inhibitors/pharmacology , Pyrazoles/pharmacology , Severe Acute Respiratory Syndrome/prevention & control , Anti-Inflammatory Agents/pharmacokinetics , Anti-Inflammatory Agents/pharmacology , Betacoronavirus/immunology , COVID-19 , Coronavirus Infections/complications , Coronavirus Infections/immunology , Coronavirus Infections/virology , Cytokine Release Syndrome/complications , Cytokine Release Syndrome/immunology , Cytokine Release Syndrome/virology , Cytokines/genetics , Cytokines/immunology , Drug Dosage Calculations , Gene Expression Regulation , Host-Pathogen Interactions/drug effects , Host-Pathogen Interactions/immunology , Humans , Janus Kinase 1/antagonists & inhibitors , Janus Kinase 1/genetics , Janus Kinase 1/immunology , Janus Kinase 2/antagonists & inhibitors , Janus Kinase 2/genetics , Janus Kinase 2/immunology , Lung/drug effects , Lung/immunology , Lung/pathology , Lung/virology , Nitriles , Pandemics , Pneumonia, Viral/complications , Pneumonia, Viral/immunology , Pneumonia, Viral/virology , Protein Kinase Inhibitors/pharmacokinetics , Pyrazoles/pharmacokinetics , Pyrimidines , SARS-CoV-2 , Severe Acute Respiratory Syndrome/complications , Severe Acute Respiratory Syndrome/immunology , Severe Acute Respiratory Syndrome/virology , Severity of Illness Index , Signal Transduction/drug effectsABSTRACT
A subgroup of patients with severe COVID-19 suffers from progression to acute respiratory distress syndrome and multiorgan failure. These patients present with progressive hyperinflammation governed by proinflammatory cytokines. An interdisciplinary COVID-19 work flow was established to detect patients with imminent or full blown hyperinflammation. Using a newly developed COVID-19 Inflammation Score (CIS), patients were prospectively stratified for targeted inhibition of cytokine signalling by the Janus Kinase 1/2 inhibitor ruxolitinib (Rux). Patients were treated with efficacy/toxicity guided step up dosing up to 14 days. Retrospective analysis of CIS reduction and clinical outcome was performed. Out of 105 patients treated between March 30th and April 15th, 2020, 14 patients with a CIS ≥ 10 out of 16 points received Rux over a median of 9 days with a median cumulative dose of 135 mg. A total of 12/14 patients achieved significant reduction of CIS by ≥25% on day 7 with sustained clinical improvement in 11/14 patients without short term red flag warnings of Rux-induced toxicity. Rux treatment for COVID-19 in patients with hyperinflammation is shown to be safe with signals of efficacy in this pilot case series for CRS-intervention to prevent or overcome multiorgan failure. A multicenter phase-II clinical trial has been initiated (NCT04338958).