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1.
Nature ; 609(7928): 754-760, 2022 09.
Article in English | MEDLINE | ID: covidwho-1984401

ABSTRACT

Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge1-5. Here we conducted a genome-wide association study (GWAS) involving 2,393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3,289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target.


Subject(s)
COVID-19 , GTPase-Activating Proteins , Genome-Wide Association Study , Guanine Nucleotide Exchange Factors , Host Microbial Interactions , SARS-CoV-2 , Alleles , Animals , COVID-19/complications , COVID-19/genetics , COVID-19/immunology , COVID-19/physiopathology , Disease Models, Animal , GTPase-Activating Proteins/antagonists & inhibitors , GTPase-Activating Proteins/genetics , GTPase-Activating Proteins/metabolism , Genetic Predisposition to Disease , Guanine Nucleotide Exchange Factors/antagonists & inhibitors , Guanine Nucleotide Exchange Factors/genetics , Guanine Nucleotide Exchange Factors/metabolism , Host Microbial Interactions/genetics , Host Microbial Interactions/immunology , Humans , Interferon Type I/genetics , Interferon Type I/immunology , Japan , Lung/pathology , Macrophages , Mesocricetus , Middle Aged , Pneumonia/complications , Pyrazoles/pharmacology , RNA-Seq , SARS-CoV-2/pathogenicity , Viral Load , Weight Loss
2.
J Virol ; 96(12): e0041222, 2022 06 22.
Article in English | MEDLINE | ID: covidwho-1874504

ABSTRACT

SARS-CoV-2 is the causative agent of the ongoing pandemic of coronavirus disease 2019 (COVID-19) and poses a significant threat to global health. N protein (NP), which is a major pathogenic protein among betacoronaviruses, binds to the viral RNA genome to allow viral genome packaging and viral particle release. Recent studies showed that NP antagonizes interferon (IFN) induction and mediates phase separation. Using live SARS-CoV-2 viruses, this study provides solid evidence showing that SARS-CoV-2 NP associates with G3BP1 and G3BP2 in vitro and in vivo. NPSARS-CoV-2 could efficiently suppress G3BP-mediated SG formation and potentiate viral infection by overcoming G3BP1-mediated antiviral innate immunity. G3BP1 conditional knockout mice (g3bp1fl/fL, Sftpc-Cre) exhibit significantly higher lung viral loads after SARS-CoV-2 infection than wild-type mice. Our findings contribute to the growing body of knowledge regarding the pathogenicity of NPSARS-CoV-2 and provide insight into new therapeutics targeting NPSARS-CoV-2. IMPORTANCE In this study, by in vitro assay and live SARS-CoV-2 virus infection, we provide solid evidence that the SARS-CoV-2 NP associates with G3BP1 and G3BP2 in vitro and in vivo. NPSARS-CoV-2 could efficiently suppress G3BP-mediated SG formation and potentiate viral infection by overcoming antiviral innate immunity mediated by G3BP1 in A549 cell lines and G3BP1 conditional knockout mice (g3bp1-cKO) mice, which provide in-depth evidence showing the mechanism underlying NP-related SARS-CoV-2 pathogenesis through G3BPs.


Subject(s)
COVID-19 , Coronavirus Nucleocapsid Proteins , Poly-ADP-Ribose Binding Proteins , SARS-CoV-2 , Virus Replication , Adaptor Proteins, Signal Transducing/metabolism , Animals , COVID-19/immunology , COVID-19/virology , Coronavirus Nucleocapsid Proteins/metabolism , DNA Helicases/metabolism , Host Microbial Interactions/immunology , Mice , Phosphoproteins/metabolism , Poly-ADP-Ribose Binding Proteins/metabolism , RNA Helicases/metabolism , RNA Recognition Motif Proteins/metabolism , RNA-Binding Proteins/metabolism , Stress Granules , Virus Replication/genetics
4.
Nat Immunol ; 23(3): 360-370, 2022 03.
Article in English | MEDLINE | ID: covidwho-1713200

ABSTRACT

Host genetic and environmental factors including age, biological sex, diet, geographical location, microbiome composition and metabolites converge to influence innate and adaptive immune responses to vaccines. Failure to understand and account for these factors when investigating severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) vaccine efficacy may impair the development of the next generation of vaccines. Most studies aimed at identifying mechanisms of vaccine-mediated immune protection have focused on adaptive immune responses. It is well established, however, that mobilization of the innate immune response is essential to the development of effective cellular and humoral immunity. A comprehensive understanding of the innate immune response and environmental factors that contribute to the development of broad and durable cellular and humoral immune responses to SARS-CoV-2 and other vaccines requires a holistic and unbiased approach. Along with optimization of the immunogen and vectors, the development of adjuvants based on our evolving understanding of how the innate immune system shapes vaccine responses will be essential. Defining the innate immune mechanisms underlying the establishment of long-lived plasma cells and memory T cells could lead to a universal vaccine for coronaviruses, a key biomedical priority.


Subject(s)
Biological Variation, Population , COVID-19 Vaccines/immunology , COVID-19/epidemiology , COVID-19/prevention & control , Host-Pathogen Interactions/immunology , Immunity , SARS-CoV-2/immunology , Antibodies, Viral , COVID-19/virology , COVID-19 Vaccines/administration & dosage , Global Health , Host Microbial Interactions/immunology , Humans , Immunity, Humoral , Immunity, Innate , Immunogenicity, Vaccine , Immunologic Memory , Microbiota/immunology , Pandemics , Public Health Surveillance , Vaccination
6.
PLoS Comput Biol ; 17(12): e1009664, 2021 12.
Article in English | MEDLINE | ID: covidwho-1571973

ABSTRACT

The evolution of circulating viruses is shaped by their need to evade antibody response, which mainly targets the viral spike. Because of the high density of spikes on the viral surface, not all antigenic sites are targeted equally by antibodies. We offer here a geometry-based approach to predict and rank the probability of surface residues of SARS spike (S protein) and influenza H1N1 spike (hemagglutinin) to acquire antibody-escaping mutations utilizing in-silico models of viral structure. We used coarse-grained MD simulations to estimate the on-rate (targeting) of an antibody model to surface residues of the spike protein. Analyzing publicly available sequences, we found that spike surface sequence diversity of the pre-pandemic seasonal influenza H1N1 and the sarbecovirus subgenus highly correlates with our model prediction of antibody targeting. In particular, we identified an antibody-targeting gradient, which matches a mutability gradient along the main axis of the spike. This identifies the role of viral surface geometry in shaping the evolution of circulating viruses. For the 2009 H1N1 and SARS-CoV-2 pandemics, a mutability gradient along the main axis of the spike was not observed. Our model further allowed us to identify key residues of the SARS-CoV-2 spike at which antibody escape mutations have now occurred. Therefore, it can inform of the likely functional role of observed mutations and predict at which residues antibody-escaping mutation might arise.


Subject(s)
Evolution, Molecular , Influenza A Virus, H1N1 Subtype/genetics , Influenza A Virus, H1N1 Subtype/immunology , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Viral Envelope Proteins/genetics , Viral Envelope Proteins/immunology , Animals , Antibodies, Viral/biosynthesis , Antigens, Viral/chemistry , Antigens, Viral/genetics , COVID-19/epidemiology , COVID-19/immunology , COVID-19/virology , Computational Biology , Coronavirus Infections/immunology , Coronavirus Infections/virology , Epitopes, B-Lymphocyte/chemistry , Epitopes, B-Lymphocyte/genetics , Hemagglutinin Glycoproteins, Influenza Virus/chemistry , Hemagglutinin Glycoproteins, Influenza Virus/genetics , Hemagglutinin Glycoproteins, Influenza Virus/immunology , Host Microbial Interactions/genetics , Host Microbial Interactions/immunology , Humans , Immune Evasion/genetics , Influenza, Human/immunology , Influenza, Human/virology , Models, Immunological , Molecular Dynamics Simulation , Mutation , Pandemics , Spike Glycoprotein, Coronavirus/chemistry , Viral Envelope Proteins/chemistry
7.
Int J Biol Macromol ; 194: 128-143, 2022 Jan 01.
Article in English | MEDLINE | ID: covidwho-1549823

ABSTRACT

The devastating impact of the ongoing coronavirus disease 2019 (COVID-19) on public health, caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) has made targeting the COVID-19 pandemic a top priority in medical research and pharmaceutical development. Surveillance of SARS-CoV-2 mutations is essential for the comprehension of SARS-CoV-2 variant diversity and their impact on virulence and pathogenicity. The SARS-CoV-2 open reading frame 10 (ORF10) protein interacts with multiple human proteins CUL2, ELOB, ELOC, MAP7D1, PPT1, RBX1, THTPA, TIMM8B, and ZYG11B expressed in lung tissue. Mutations and co-occurring mutations in the emerging SARS-CoV-2 ORF10 variants are expected to impact the severity of the virus and its associated consequences. In this article, we highlight 128 single mutations and 35 co-occurring mutations in the unique SARS-CoV-2 ORF10 variants. The possible predicted effects of these mutations and co-occurring mutations on the secondary structure of ORF10 variants and host protein interactomes are presented. The findings highlight the possible effects of mutations and co-occurring mutations on the emerging 140 ORF10 unique variants from secondary structure and intrinsic protein disorder perspectives.


Subject(s)
COVID-19/virology , Host Microbial Interactions/immunology , Open Reading Frames , SARS-CoV-2/genetics , Viral Proteins , Humans , Mutation , Viral Proteins/genetics , Viral Proteins/immunology
8.
PLoS Comput Biol ; 17(11): e1009587, 2021 11.
Article in English | MEDLINE | ID: covidwho-1533401

ABSTRACT

Patients with coronavirus disease 2019 (COVID-19) often exhibit diverse disease progressions associated with various infectious ability, symptoms, and clinical treatments. To systematically and thoroughly understand the heterogeneous progression of COVID-19, we developed a multi-scale computational model to quantitatively understand the heterogeneous progression of COVID-19 patients infected with severe acute respiratory syndrome (SARS)-like coronavirus (SARS-CoV-2). The model consists of intracellular viral dynamics, multicellular infection process, and immune responses, and was formulated using a combination of differential equations and stochastic modeling. By integrating multi-source clinical data with model analysis, we quantified individual heterogeneity using two indexes, i.e., the ratio of infected cells and incubation period. Specifically, our simulations revealed that increasing the host antiviral state or virus induced type I interferon (IFN) production rate can prolong the incubation period and postpone the transition from asymptomatic to symptomatic outcomes. We further identified the threshold dynamics of T cell exhaustion in the transition between mild-moderate and severe symptoms, and that patients with severe symptoms exhibited a lack of naïve T cells at a late stage. In addition, we quantified the efficacy of treating COVID-19 patients and investigated the effects of various therapeutic strategies. Simulations results suggested that single antiviral therapy is sufficient for moderate patients, while combination therapies and prevention of T cell exhaustion are needed for severe patients. These results highlight the critical roles of IFN and T cell responses in regulating the stage transition during COVID-19 progression. Our study reveals a quantitative relationship underpinning the heterogeneity of transition stage during COVID-19 progression and can provide a potential guidance for personalized therapy in COVID-19 patients.


Subject(s)
COVID-19/etiology , SARS-CoV-2 , Antiviral Agents/therapeutic use , COVID-19/immunology , COVID-19/therapy , Computational Biology , Computer Simulation , Disease Progression , Host Microbial Interactions/immunology , Humans , Interferon Type I/biosynthesis , Lymphocyte Activation , Models, Immunological , Models, Statistical , Pandemics/statistics & numerical data , Prognosis , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Severity of Illness Index , T-Lymphocytes/immunology , Treatment Outcome
9.
Biochem Biophys Res Commun ; 586: 87-92, 2022 01 01.
Article in English | MEDLINE | ID: covidwho-1525697

ABSTRACT

There is an urgent need to understand the functional effects of mutations in emerging variants of SARS-CoV-2. Variants of concern (alpha, beta, gamma and delta) acquired four patterns of spike glycoprotein mutations that enhance transmissibility and immune evasion: 1) mutations in the N-terminal domain (NTD), 2) mutations in the Receptor Binding Domain (RBD), 3) mutations at interchain contacts of the spike trimer, and 4) furin cleavage site mutations. Most distinguishing mutations among variants of concern are exhibited in the NTD, localized to sites of high structural flexibility. Emerging variants of interest such as mu, lambda and C.1.2 exhibit the same patterns of mutations as variants of concern. There is a strong likelihood that SARS-CoV-2 variants will continue to emerge with mutations in these defined patterns, thus providing a basis for the development of next line antiviral drugs and vaccine candidates.


Subject(s)
COVID-19/virology , Mutation , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Amino Acid Sequence , Antibodies, Neutralizing/biosynthesis , Antibodies, Viral/biosynthesis , COVID-19/immunology , COVID-19/transmission , Evolution, Molecular , Host Microbial Interactions/genetics , Host Microbial Interactions/immunology , Humans , Models, Molecular , Pandemics , Protein Conformation , Protein Interaction Domains and Motifs/genetics , Protein Interaction Domains and Motifs/immunology , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/immunology
10.
Front Immunol ; 12: 693938, 2021.
Article in English | MEDLINE | ID: covidwho-1523694

ABSTRACT

More than one and a half years have elapsed since the commencement of the coronavirus disease 2019 (COVID-19) pandemic, and the world is struggling to contain it. Being caused by a previously unknown virus, in the initial period, there had been an extreme paucity of knowledge about the disease mechanisms, which hampered preventive and therapeutic measures against COVID-19. In an endeavor to understand the pathogenic mechanisms, extensive experimental studies have been conducted across the globe involving cell culture-based experiments, human tissue organoids, and animal models, targeted to various aspects of the disease, viz., viral properties, tissue tropism and organ-specific pathogenesis, involvement of physiological systems, and the human immune response against the infection. The vastly accumulated scientific knowledge on all aspects of COVID-19 has currently changed the scenario from great despair to hope. Even though spectacular progress has been made in all of these aspects, multiple knowledge gaps are remaining that need to be addressed in future studies. Moreover, multiple severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have emerged across the globe since the onset of the first COVID-19 wave, with seemingly greater transmissibility/virulence and immune escape capabilities than the wild-type strain. In this review, we narrate the progress made since the commencement of the pandemic regarding the knowledge on COVID-19 mechanisms in the human body, including virus-host interactions, pulmonary and other systemic manifestations, immunological dysregulations, complications, host-specific vulnerability, and long-term health consequences in the survivors. Additionally, we provide a brief review of the current evidence explaining molecular mechanisms imparting greater transmissibility and virulence and immune escape capabilities to the emerging SARS-CoV-2 variants.


Subject(s)
COVID-19/immunology , COVID-19/virology , Host Microbial Interactions/immunology , Animals , Human Body , Humans , Lung/immunology , Lung/virology , Pandemics/prevention & control , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity
11.
Clin Transl Sci ; 14(6): 2348-2359, 2021 11.
Article in English | MEDLINE | ID: covidwho-1526356

ABSTRACT

Coronavirus disease 2019 (COVID-19) global pandemic is caused by severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) viral infection, which can lead to pneumonia, lung injury, and death in susceptible populations. Understanding viral dynamics of SARS-CoV-2 is critical for development of effective treatments. An Immune-Viral Dynamics Model (IVDM) is developed to describe SARS-CoV-2 viral dynamics and COVID-19 disease progression. A dataset of 60 individual patients with COVID-19 with clinical viral load (VL) and reported disease severity were assembled from literature. Viral infection and replication mechanisms of SARS-CoV-2, viral-induced cell death, and time-dependent immune response are incorporated in the model to describe the dynamics of viruses and immune response. Disease severity are tested as a covariate to model parameters. The IVDM was fitted to the data and parameters were estimated using the nonlinear mixed-effect model. The model can adequately describe individual viral dynamics profiles, with disease severity identified as a covariate on infected cell death rate. The modeling suggested that it takes about 32.6 days to reach 50% of maximum cell-based immunity. Simulations based on virtual populations suggested a typical mild case reaches VL limit of detection (LOD) by 13 days with no treatment, a moderate case by 17 days, and a severe case by 41 days. Simulations were used to explore hypothetical treatments with different initiation time, disease severity, and drug effects to demonstrate the usefulness of such modeling in informing decisions. Overall, the IVDM modeling and simulation platform enables simulations for viral dynamics and treatment efficacy and can be used to aid in clinical pharmacokinetic/pharmacodynamic (PK/PD) and dose-efficacy response analysis for COVID-19 drug development.


Subject(s)
Antiviral Agents/pharmacology , COVID-19/drug therapy , Drug Development/methods , Host Microbial Interactions/immunology , Models, Biological , Antiviral Agents/therapeutic use , COVID-19/diagnosis , COVID-19/immunology , COVID-19/virology , Cell Death/drug effects , Cell Death/immunology , Datasets as Topic , Dose-Response Relationship, Drug , Host Microbial Interactions/drug effects , Humans , Nonlinear Dynamics , SARS-CoV-2/drug effects , SARS-CoV-2/immunology , Severity of Illness Index , Treatment Outcome , Viral Load
12.
J Virol ; 96(2): e0167821, 2022 01 26.
Article in English | MEDLINE | ID: covidwho-1511415

ABSTRACT

The positive-sense, single-stranded RNA genome SARS-CoV-2 harbors functionally important cis-acting elements governing critical aspects of viral gene expression. However, insights on how these elements sense various signals from the host cell and regulate viral protein synthesis are lacking. Here, we identified two novel cis-regulatory elements in SARS-CoV-2 ORF1a and S RNAs and describe their role in translational control of SARS-CoV-2. These elements are sequence-unrelated but form conserved hairpin structures (validated by NMR) resembling gamma activated inhibitor of translation (GAIT) elements that are found in a cohort of human mRNAs directing translational suppression in myeloid cells in response to IFN-γ. Our studies show that treatment of human lung cells with receptor-binding S1 subunit, S protein pseudotyped lentivirus, and S protein-containing virus-like particles triggers a signaling pathway involving DAP-kinase1 that leads to phosphorylation and release of the ribosomal protein L13a from the large ribosomal subunit. Released L13a forms a virus activated inhibitor of translation (VAIT) complex that binds to ORF1a and S VAIT elements, causing translational silencing. Translational silencing requires extracellular S protein (and its interaction with host ACE2 receptor), but not its intracellular synthesis. RNA-protein interaction analyses and in vitro translation experiments showed that GAIT and VAIT elements do not compete with each other, highlighting differences between the two pathways. Sequence alignments of SARS-CoV-2 genomes showed a high level of conservation of VAIT elements, suggesting their functional importance. This VAIT-mediated translational control mechanism of SARS-CoV-2 may provide novel targets for small molecule intervention and/or facilitate development of more effective mRNA vaccines. IMPORTANCE Specific RNA elements in the genomes of RNA viruses play important roles in host-virus interaction. For SARS-CoV-2, the mechanistic insights on how these RNA elements could sense the signals from the host cell are lacking. Here we report a novel relationship between the GAIT-like SARS-CoV-2 RNA element (called VAITs) and the signal generated from the host cell. We show that for SARS-CoV-2, the interaction of spike protein with ACE2 not only serves the purpose for viral entry into the host cell, but also transduces signals that culminate into the phosphorylation and the release of L13a from the large ribosomal subunit. We also show that this event leads to the translational arrest of ORF1a and S mRNAs in a manner dependent on the structure of the RNA elements. Translational control of viral mRNA by a host-cell generated signal triggered by viral protein is a new paradigm in the host-virus relationship.


Subject(s)
COVID-19 , Host Microbial Interactions , RNA, Viral/immunology , SARS-CoV-2 , A549 Cells , COVID-19/immunology , COVID-19/virology , Host Microbial Interactions/genetics , Host Microbial Interactions/immunology , Humans , Protein Binding , SARS-CoV-2/genetics , SARS-CoV-2/immunology , Virus Internalization
13.
J Photochem Photobiol B ; 226: 112357, 2022 Jan.
Article in English | MEDLINE | ID: covidwho-1510060

ABSTRACT

Mitochondrial antiviral signaling (MAVS) protein mediates innate antiviral responses, including responses to certain coronaviruses such as severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). We have previously shown that ultraviolet-A (UVA) therapy can prevent virus-induced cell death in human ciliated tracheal epithelial cells (HTEpC) infected with coronavirus-229E (CoV-229E), and results in increased intracellular levels of MAVS. In this study, we explored the mechanisms by which UVA light can activate MAVS, and whether local UVA light application can activate MAVS at locations distant from the light source (e.g. via cell-to-cell communication). MAVS levels were compared in HTEpC exposed to 2 mW/cm2 narrow band (NB)-UVA for 20 min and in unexposed controls at 30-40% and at 100% confluency, and in unexposed HTEpC treated with supernatants or lysates from UVA-exposed cells or from unexposed controls. MAVS was also assessed in different sections of confluent monolayer plates where only one section was exposed to NB-UVA. Our results showed that UVA increases the expression of MAVS protein. Further, cells in a confluent monolayer exposed to UVA conferred an elevation in MAVS in cells adjacent to the exposed section, and also in cells in the most distant sections which were not exposed to UVA. In this study, human ciliated tracheal epithelial cells exposed to UVA demonstrate increased MAVS protein, and also appear to transmit this influence to confluent cells not exposed to UVA, likely via cell-cell signaling.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Adaptor Proteins, Signal Transducing/radiation effects , Ultraviolet Rays , Adaptor Proteins, Signal Transducing/immunology , COVID-19/immunology , COVID-19/radiotherapy , COVID-19/virology , Cell Communication/immunology , Cell Communication/radiation effects , Cells, Cultured , Epithelial Cells/immunology , Epithelial Cells/radiation effects , Host Microbial Interactions/immunology , Host Microbial Interactions/radiation effects , Humans , Immunity, Innate/radiation effects , Photobiology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Signal Transduction/immunology , Signal Transduction/radiation effects , Trachea/cytology , Ultraviolet Therapy
14.
J Clin Invest ; 131(21)2021 11 01.
Article in English | MEDLINE | ID: covidwho-1495789

ABSTRACT

To explore how the immune system controls clearance of SARS-CoV-2, we used a single-cell, mass cytometry-based proteomics platform to profile the immune systems of 21 patients who had recovered from SARS-CoV-2 infection without need for admission to an intensive care unit or for mechanical ventilation. We focused on receptors involved in interactions between immune cells and virus-infected cells. We found that the diversity of receptor repertoires on natural killer (NK) cells was negatively correlated with the viral clearance rate. In addition, NK subsets expressing the receptor DNAM1 were increased in patients who more rapidly recovered from infection. Ex vivo functional studies revealed that NK subpopulations with high DNAM1 expression had cytolytic activities in response to target cell stimulation. We also found that SARS-CoV-2 infection induced the expression of CD155 and nectin-4, ligands of DNAM1 and its paired coinhibitory receptor TIGIT, which counterbalanced the cytolytic activities of NK cells. Collectively, our results link the cytolytic immune responses of NK cells to the clearance of SARS-CoV-2 and show that the DNAM1 pathway modulates host-pathogen interactions during SARS-CoV-2 infection.


Subject(s)
COVID-19/immunology , COVID-19/virology , Killer Cells, Natural/immunology , Receptors, Natural Killer Cell/immunology , SARS-CoV-2/immunology , Adolescent , Adult , Aged , Animals , Antigens, Differentiation, T-Lymphocyte/immunology , Cell Adhesion Molecules/immunology , Cohort Studies , Cytotoxicity, Immunologic , Female , Heterografts , Host Microbial Interactions/immunology , Humans , Immunophenotyping , In Vitro Techniques , Ligands , Male , Mice , Mice, SCID , Middle Aged , NK Cell Lectin-Like Receptor Subfamily D/immunology , Pandemics , Receptors, Immunologic/immunology , Receptors, Virus/immunology , Viral Load , Young Adult
15.
Hamostaseologie ; 41(5): 387-396, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1483190

ABSTRACT

Hypercoagulability and vascular injury, which characterize morbidity in COVID-19 disease, are frequently observed in the skin. Several pathomechanisms, such as inflammation caused by angiotensin-converting enzyme 2-mediated uptake into endothelial cells or SARS-CoV-2-initiated host immune responses, contribute to microthrombus formation and the appearance of vascular skin lesions. Besides pathophysiologic mechanisms observed in the skin, this review describes the clinical appearance of cutaneous vascular lesions and their association with COVID-19 disease, including acro-ischemia, reticular lesions, and cutaneous small vessel vasculitis. Clinicians need to be aware that skin manifestations may be the only symptom in SARS-CoV-2 infection, and that inflammatory and thrombotic SARS-CoV-2-driven processes observed in multiple organs and tissues appear identically in the skin as well.


Subject(s)
COVID-19/complications , SARS-CoV-2 , Skin/blood supply , Angiotensin-Converting Enzyme 2/physiology , Antibodies, Antiphospholipid/blood , Blood Coagulation Disorders/blood , Blood Coagulation Disorders/etiology , Blood Coagulation Disorders/pathology , COVID-19/pathology , COVID-19/physiopathology , Complement Activation , Cytokines/metabolism , Host Microbial Interactions/immunology , Host Microbial Interactions/physiology , Humans , Microvessels/immunology , Microvessels/pathology , Microvessels/physiopathology , Pandemics , SARS-CoV-2/pathogenicity , SARS-CoV-2/physiology , Skin/immunology , Vasculitis/etiology , Vasculitis/pathology , Vasculitis/physiopathology , Virus Internalization
16.
Hamostaseologie ; 41(5): 372-378, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1483189

ABSTRACT

Since the coronavirus disease (COVID-19) pandemic spread unrelentingly all over the world, millions of cases have been reported. Despite a high number of asymptomatic cases, the course of the disease can be serious or even fatal. The affection of the myocardium, called myocardial injury, is caused by multiple triggers. The occurrence of cardiac arrhythmias in COVID-19 patients with myocardial involvement and a critical course is common. In this review, potential mechanisms, incidence, and treatment options for cardiac arrhythmias in COVID-19 patients will be provided by performing a literature research in MESH database and the National Library of Medicine. Common cardiac arrhythmias in COVID-19 patients were sinus tachycardia, atrial fibrillation (AF), ventricular tachycardia (VT), ventricular fibrillation (VF), atrioventricular block, sinusoidal block or QTc prolongation. AF was the most common heart rhythm disorder. About 10% of COVID-19 patients develop new-onset AF and 23 to 33% showed recurrence of AF in patients with known AF. One retrospective trial revealed the incidence of VT or VF to be 5.9% in hospitalized patients. Both AF and VT are clearly associated with worse outcome. Several mechanisms such as hypoxia, myocarditis, myocardial ischemia, or abnormal host immune response, which induce cardiac arrhythmias, have been described. The effect of QT-prolonging drugs in inducing cardiac arrhythmias has become mitigated as these medications are no longer recommended. Acute management of cardiac arrhythmias in COVID-19 patients is affected by the reduction of exposure of health care personnel. More prospective data are desirable to better understand pathophysiology and consecutively adapt management.


Subject(s)
Arrhythmias, Cardiac/etiology , COVID-19/complications , SARS-CoV-2 , Arrhythmias, Cardiac/epidemiology , Arrhythmias, Cardiac/physiopathology , Atrial Fibrillation/etiology , COVID-19/physiopathology , COVID-19/virology , Host Microbial Interactions/immunology , Humans , Myocardial Ischemia/etiology , Myocarditis/etiology , SARS-CoV-2/immunology , SARS-CoV-2/pathogenicity , Tachycardia, Ventricular/etiology , Water-Electrolyte Imbalance/etiology
17.
Hamostaseologie ; 41(5): 379-385, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1483188

ABSTRACT

In 2019 first reports about a new human coronavirus emerged, which causes common cold symptoms as well as acute respiratory distress syndrome. The virus was identified as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and severe thrombotic events including deep vein thrombosis, pulmonary embolism, and microthrombi emerged as additional symptoms. Heart failure, myocardial infarction, myocarditis, and stroke have also been observed. As main mediator of thrombus formation, platelets became one of the key aspects in SARS-CoV-2 research. Platelets may also directly interact with SARS-CoV-2 and have been shown to carry the SARS-CoV-2 virus. Platelets can also facilitate the virus uptake by secretion of the subtilisin-like proprotein convertase furin. Cleavage of the SARS-CoV-2 spike protein by furin enhances binding capabilities and virus entry into various cell types. In COVID-19 patients, platelet count differs between mild and serious infections. Patients with mild symptoms have a slightly increased platelet count, whereas thrombocytopenia is a hallmark of severe COVID-19 infections. Low platelet count can be attributed to platelet apoptosis and the incorporation of platelets into microthrombi (peripheral consumption) and severe thrombotic events. The observed excessive formation of thrombi is due to hyperactivation of platelets caused by the infection. Various factors have been suggested in the activation of platelets in COVID-19, such as hypoxia, vessel damage, inflammatory factors, NETosis, SARS-CoV-2 interaction, autoimmune reactions, and autocrine activation. COVID-19 does alter chemokine and cytokine plasma concentrations. Platelet chemokine profiles are altered in COVID-19 and contribute to the described chemokine storms observed in severely ill COVID-19 patients.


Subject(s)
Blood Platelets/physiology , Blood Platelets/virology , COVID-19/blood , Blood Platelets/immunology , COVID-19/complications , COVID-19/immunology , Chemokines/blood , Cytokine Release Syndrome/blood , Cytokine Release Syndrome/etiology , Host Microbial Interactions/immunology , Host Microbial Interactions/physiology , Humans , Models, Biological , Pandemics , Platelet Activation/immunology , Platelet Activation/physiology , SARS-CoV-2/pathogenicity , Thrombosis/blood , Thrombosis/etiology
18.
Mol Syst Biol ; 17(10): e10387, 2021 10.
Article in English | MEDLINE | ID: covidwho-1478718

ABSTRACT

We need to effectively combine the knowledge from surging literature with complex datasets to propose mechanistic models of SARS-CoV-2 infection, improving data interpretation and predicting key targets of intervention. Here, we describe a large-scale community effort to build an open access, interoperable and computable repository of COVID-19 molecular mechanisms. The COVID-19 Disease Map (C19DMap) is a graphical, interactive representation of disease-relevant molecular mechanisms linking many knowledge sources. Notably, it is a computational resource for graph-based analyses and disease modelling. To this end, we established a framework of tools, platforms and guidelines necessary for a multifaceted community of biocurators, domain experts, bioinformaticians and computational biologists. The diagrams of the C19DMap, curated from the literature, are integrated with relevant interaction and text mining databases. We demonstrate the application of network analysis and modelling approaches by concrete examples to highlight new testable hypotheses. This framework helps to find signatures of SARS-CoV-2 predisposition, treatment response or prioritisation of drug candidates. Such an approach may help deal with new waves of COVID-19 or similar pandemics in the long-term perspective.


Subject(s)
COVID-19/immunology , Computational Biology/methods , Databases, Factual , SARS-CoV-2/immunology , Software , Antiviral Agents/therapeutic use , COVID-19/drug therapy , COVID-19/genetics , COVID-19/virology , Computer Graphics , Cytokines/genetics , Cytokines/immunology , Data Mining/statistics & numerical data , Gene Expression Regulation , Host Microbial Interactions/genetics , Host Microbial Interactions/immunology , Humans , Immunity, Cellular/drug effects , Immunity, Humoral/drug effects , Immunity, Innate/drug effects , Lymphocytes/drug effects , Lymphocytes/immunology , Lymphocytes/virology , Metabolic Networks and Pathways/genetics , Metabolic Networks and Pathways/immunology , Myeloid Cells/drug effects , Myeloid Cells/immunology , Myeloid Cells/virology , Protein Interaction Mapping , SARS-CoV-2/drug effects , SARS-CoV-2/genetics , SARS-CoV-2/pathogenicity , Signal Transduction , Transcription Factors/genetics , Transcription Factors/immunology , Viral Proteins/genetics , Viral Proteins/immunology
19.
Eur J Immunol ; 51(7): 1641-1651, 2021 07.
Article in English | MEDLINE | ID: covidwho-1473829

ABSTRACT

Emerging life-threatening viruses have posed great challenges to public health. It is now increasingly clear that epigenetics plays a role in shaping host-virus interactions and there is a great need for a more thorough understanding of these intricate interactions through the epigenetic lens, which may represent potential therapeutic opportunities in the clinic. In this review, we highlight the current understanding of the roles of key epigenetic regulators - chromatin remodeling and histone modification - in modulating chromatin openness during host defense against virus. We also discuss how the RNA modification m6A (N6-methyladenosine) affects fundamental aspects of host-virus interactions. We conclude with future directions for uncovering more detailed functions that epigenetic regulation exerts on both host cells and viruses during infection.


Subject(s)
Antiviral Agents/immunology , Epigenesis, Genetic/genetics , Epigenesis, Genetic/immunology , Immunity, Innate/genetics , Immunity, Innate/immunology , Animals , Chromatin/genetics , Chromatin/immunology , Histones/genetics , Histones/immunology , Host Microbial Interactions/genetics , Host Microbial Interactions/immunology , Humans , RNA Processing, Post-Transcriptional/genetics , RNA Processing, Post-Transcriptional/immunology
20.
J Clin Invest ; 131(21)2021 11 01.
Article in English | MEDLINE | ID: covidwho-1403157

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the cause of coronavirus disease 2019 (COVID-19). Little is known about the interplay between preexisting immunity to endemic seasonal coronaviruses and the development of a SARS-CoV-2-specific IgG response. We investigated the kinetics, breadth, magnitude, and level of cross-reactivity of IgG antibodies against SARS-CoV-2 and heterologous seasonal and epidemic coronaviruses at the clonal level in patients with mild or severe COVID-19 as well as in disease control patients. We assessed antibody reactivity to nucleocapsid and spike antigens and correlated this IgG response to SARS-CoV-2 neutralization. Patients with COVID-19 mounted a mostly type-specific SARS-CoV-2 response. Additionally, IgG clones directed against a seasonal coronavirus were boosted in patients with severe COVID-19. These boosted clones showed limited cross-reactivity and did not neutralize SARS-CoV-2. These findings indicate a boost of poorly protective CoV-specific antibodies in patients with COVID-19 that correlated with disease severity, revealing "original antigenic sin."


Subject(s)
B-Lymphocytes/immunology , B-Lymphocytes/virology , COVID-19/immunology , COVID-19/virology , Coronavirus/immunology , SARS-CoV-2/immunology , Adult , Aged , Antibodies, Neutralizing/blood , Antibodies, Viral/blood , Antibody Specificity , Case-Control Studies , Coronavirus Infections/immunology , Coronavirus Infections/virology , Coronavirus Nucleocapsid Proteins/immunology , Cross Reactions , Female , Host Microbial Interactions/immunology , Humans , Immunoglobulin G/blood , Longitudinal Studies , Male , Middle Aged , Pandemics , Phosphoproteins/immunology , Seasons , Severity of Illness Index , Spike Glycoprotein, Coronavirus/immunology
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