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1.
Nature ; 591(7848): 124-130, 2021 03.
Article in English | MEDLINE | ID: covidwho-1368933

ABSTRACT

Although infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has pleiotropic and systemic effects in some individuals1-3, many others experience milder symptoms. Here, to gain a more comprehensive understanding of the distinction between severe and mild phenotypes in the pathology of coronavirus disease 2019 (COVID-19) and its origins, we performed a whole-blood-preserving single-cell analysis protocol to integrate contributions from all major immune cell types of the blood-including neutrophils, monocytes, platelets, lymphocytes and the contents of the serum. Patients with mild COVID-19 exhibit a coordinated pattern of expression of interferon-stimulated genes (ISGs)3 across every cell population, whereas these ISG-expressing cells are systemically absent in patients with severe disease. Paradoxically, individuals with severe COVID-19 produce very high titres of anti-SARS-CoV-2 antibodies and have a lower viral load compared to individuals with mild disease. Examination of the serum from patients with severe COVID-19 shows that these patients uniquely produce antibodies that functionally block the production of the ISG-expressing cells associated with mild disease, by activating conserved signalling circuits that dampen cellular responses to interferons. Overzealous antibody responses pit the immune system against itself in many patients with COVID-19, and perhaps also in individuals with other viral infections. Our findings reveal potential targets for immunotherapies in patients with severe COVID-19 to re-engage viral defence.


Subject(s)
Antibodies, Viral/immunology , COVID-19/immunology , COVID-19/physiopathology , Interferons/antagonists & inhibitors , Interferons/immunology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Antibodies, Viral/blood , Antibody Formation , Base Sequence , COVID-19/blood , COVID-19/virology , Female , Humans , Immunoglobulin G/immunology , Interferons/metabolism , Male , Neutrophils/immunology , Neutrophils/pathology , Protein Domains , Receptor, Interferon alpha-beta/antagonists & inhibitors , Receptor, Interferon alpha-beta/immunology , Receptor, Interferon alpha-beta/metabolism , Receptors, IgG/immunology , Single-Cell Analysis , Viral Load/immunology
2.
Cell Rep ; 35(7): 109126, 2021 05 18.
Article in English | MEDLINE | ID: covidwho-1222854

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) evades most innate immune responses but may still be vulnerable to some. Here, we systematically analyze the impact of SARS-CoV-2 proteins on interferon (IFN) responses and autophagy. We show that SARS-CoV-2 proteins synergize to counteract anti-viral immune responses. For example, Nsp14 targets the type I IFN receptor for lysosomal degradation, ORF3a prevents fusion of autophagosomes and lysosomes, and ORF7a interferes with autophagosome acidification. Most activities are evolutionarily conserved. However, SARS-CoV-2 Nsp15 antagonizes IFN signaling less efficiently than the orthologs of closely related RaTG13-CoV and SARS-CoV-1. Overall, SARS-CoV-2 proteins counteract autophagy and type I IFN more efficiently than type II or III IFN signaling, and infection experiments confirm potent inhibition by IFN-γ and -λ1. Our results define the repertoire and selected mechanisms of SARS-CoV-2 innate immune antagonists but also reveal vulnerability to type II and III IFN that may help to develop safe and effective anti-viral approaches.


Subject(s)
COVID-19/virology , SARS-CoV-2/immunology , Viral Proteins/immunology , Animals , Antiviral Agents/pharmacology , Autophagosomes/immunology , Autophagy/immunology , COVID-19/immunology , Cell Line , Chlorocebus aethiops , Exoribonucleases/immunology , HEK293 Cells , HeLa Cells , Humans , Immune Evasion , Immunity, Innate , Interferon Type I/metabolism , Interferons/metabolism , Receptor, Interferon alpha-beta/antagonists & inhibitors , Receptor, Interferon alpha-beta/immunology , SARS-CoV-2/pathogenicity , Vero Cells , Viral Nonstructural Proteins/immunology
3.
J Exp Med ; 218(4)2021 04 05.
Article in English | MEDLINE | ID: covidwho-1066211

ABSTRACT

Yellow fever virus (YFV) live attenuated vaccine can, in rare cases, cause life-threatening disease, typically in patients with no previous history of severe viral illness. Autosomal recessive (AR) complete IFNAR1 deficiency was reported in one 12-yr-old patient. Here, we studied seven other previously healthy patients aged 13 to 80 yr with unexplained life-threatening YFV vaccine-associated disease. One 13-yr-old patient had AR complete IFNAR2 deficiency. Three other patients vaccinated at the ages of 47, 57, and 64 yr had high titers of circulating auto-Abs against at least 14 of the 17 individual type I IFNs. These antibodies were recently shown to underlie at least 10% of cases of life-threatening COVID-19 pneumonia. The auto-Abs were neutralizing in vitro, blocking the protective effect of IFN-α2 against YFV vaccine strains. AR IFNAR1 or IFNAR2 deficiency and neutralizing auto-Abs against type I IFNs thus accounted for more than half the cases of life-threatening YFV vaccine-associated disease studied here. Previously healthy subjects could be tested for both predispositions before anti-YFV vaccination.


Subject(s)
Antibodies, Neutralizing/immunology , Autoantibodies/immunology , Autoimmune Diseases , COVID-19 , Genetic Diseases, Inborn , Interferon-alpha , Receptor, Interferon alpha-beta , SARS-CoV-2 , Yellow Fever Vaccine , Yellow fever virus , Adolescent , Adult , Aged , Autoimmune Diseases/genetics , Autoimmune Diseases/immunology , COVID-19/genetics , COVID-19/immunology , Female , Genetic Diseases, Inborn/genetics , Genetic Diseases, Inborn/immunology , HEK293 Cells , Humans , Interferon-alpha/genetics , Interferon-alpha/immunology , Male , Middle Aged , Receptor, Interferon alpha-beta/deficiency , Receptor, Interferon alpha-beta/immunology , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Vaccines, Attenuated/genetics , Vaccines, Attenuated/immunology , Yellow Fever Vaccine/adverse effects , Yellow Fever Vaccine/genetics , Yellow Fever Vaccine/immunology , Yellow fever virus/genetics , Yellow fever virus/immunology
4.
J Exp Med ; 217(12)2020 12 07.
Article in English | MEDLINE | ID: covidwho-726090

ABSTRACT

Type I interferons (IFN-I) are a major antiviral defense and are critical for the activation of the adaptive immune system. However, early viral clearance by IFN-I could limit antigen availability, which could in turn impinge upon the priming of the adaptive immune system. In this study, we hypothesized that transient IFN-I blockade could increase antigen presentation after acute viral infection. To test this hypothesis, we infected mice with viruses coadministered with a single dose of IFN-I receptor-blocking antibody to induce a short-term blockade of the IFN-I pathway. This resulted in a transient "spike" in antigen levels, followed by rapid antigen clearance. Interestingly, short-term IFN-I blockade after coronavirus, flavivirus, rhabdovirus, or arenavirus infection induced a long-lasting enhancement of immunological memory that conferred improved protection upon subsequent reinfections. Short-term IFN-I blockade also improved the efficacy of viral vaccines. These findings demonstrate a novel mechanism by which IFN-I regulate immunological memory and provide insights for rational vaccine design.


Subject(s)
Immunogenicity, Vaccine/immunology , Interferon Type I/antagonists & inhibitors , Interferon-alpha/immunology , Receptor, Interferon alpha-beta/immunology , Viral Vaccines/immunology , Zika Virus Infection/immunology , Zika Virus/immunology , Animals , Antibodies, Blocking/immunology , Antibodies, Blocking/pharmacology , Antibodies, Viral/immunology , Antigen Presentation/immunology , CD8-Positive T-Lymphocytes/metabolism , Dendritic Cells/immunology , Disease Models, Animal , Gene Expression/immunology , HEK293 Cells , Humans , Immunologic Memory , Interferon-alpha/genetics , Mice , Mice, Inbred BALB C , Mice, Inbred C57BL , Mice, Knockout , Receptor, Interferon alpha-beta/genetics , Transfection , Zika Virus Infection/virology
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