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1.
Nat Commun ; 13(1): 405, 2022 01 20.
Article in English | MEDLINE | ID: covidwho-1631967

ABSTRACT

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused the pandemic of the coronavirus induced disease 2019 (COVID-19) with evolving variants of concern. It remains urgent to identify novel approaches against broad strains of SARS-CoV-2, which infect host cells via the entry receptor angiotensin-converting enzyme 2 (ACE2). Herein, we report an increase in circulating extracellular vesicles (EVs) that express ACE2 (evACE2) in plasma of COVID-19 patients, which levels are associated with severe pathogenesis. Importantly, evACE2 isolated from human plasma or cells neutralizes SARS-CoV-2 infection by competing with cellular ACE2. Compared to vesicle-free recombinant human ACE2 (rhACE2), evACE2 shows a 135-fold higher potency in blocking the binding of the viral spike protein RBD, and a 60- to 80-fold higher efficacy in preventing infections by both pseudotyped and authentic SARS-CoV-2. Consistently, evACE2 protects the hACE2 transgenic mice from SARS-CoV-2-induced lung injury and mortality. Furthermore, evACE2 inhibits the infection of SARS-CoV-2 variants (α, ß, and δ) with equal or higher potency than for the wildtype strain, supporting a broad-spectrum antiviral mechanism of evACE2 for therapeutic development to block the infection of existing and future coronaviruses that use the ACE2 receptor.


Subject(s)
Angiotensin-Converting Enzyme 2/immunology , COVID-19/immunology , Extracellular Vesicles/immunology , SARS-CoV-2/immunology , A549 Cells , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , COVID-19/blood , COVID-19/epidemiology , Chlorocebus aethiops , Extracellular Vesicles/genetics , Extracellular Vesicles/metabolism , HEK293 Cells , HeLa Cells , Humans , Mice, Transgenic , Neutralization Tests/methods , Pandemics/prevention & control , Protein Binding , SARS-CoV-2/genetics , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Survival Analysis , Vero Cells
2.
Frontiers in immunology ; 12, 2021.
Article in English | EuropePMC | ID: covidwho-1610187

ABSTRACT

Infection with the novel coronavirus, SARS-CoV-2, results in pneumonia and other respiratory symptoms as well as pathologies at diverse anatomical sites. An outstanding question is whether these diverse pathologies are due to replication of the virus in these anatomical compartments and how and when the virus reaches those sites. To answer these outstanding questions and study the spatiotemporal dynamics of SARS-CoV-2 infection a method for tracking viral spread in vivo is needed. We developed a novel, fluorescently labeled, antibody-based in vivo probe system using the anti-spike monoclonal antibody CR3022 and demonstrated that it could successfully identify sites of SARS-CoV-2 infection in a rhesus macaque model of COVID-19. Our results showed that the fluorescent signal from our antibody-based probe could differentiate whole lungs of macaques infected for 9 days from those infected for 2 or 3 days. Additionally, the probe signal corroborated the frequency and density of infected cells in individual tissue blocks from infected macaques. These results provide proof of concept for the use of in vivo antibody-based probes to study SARS-CoV-2 infection dynamics in rhesus macaques.

3.
Front Cell Infect Microbiol ; 11: 753444, 2021.
Article in English | MEDLINE | ID: covidwho-1555153

ABSTRACT

SARS-CoV-2 is a respiratory borne pathogenic beta coronavirus that is the source of a worldwide pandemic and the cause of multiple pathologies in man. The rhesus macaque model of COVID-19 was utilized to test the added benefit of combinatory parenteral administration of two high-affinity anti-SARS-CoV-2 monoclonal antibodies (mAbs; C144-LS and C135-LS) expressly developed to neutralize the virus and modified to extend their pharmacokinetics. After completion of kinetics study of mAbs in the primate, combination treatment was administered prophylactically to mucosal viral challenge. Results showed near complete virus neutralization evidenced by no measurable titer in mucosal tissue swabs, muting of cytokine/chemokine response, and lack of any discernable pathologic sequalae. Blocking infection was a dose-related effect, cohorts receiving lower doses (6, 2 mg/kg) resulted in low grade viral infection in various mucosal sites compared to that of a fully protective dose (20 mg/kg). A subset of animals within this cohort whose infectious challenge was delayed 75 days later after mAb administration were still protected from disease. Results indicate this combination mAb effectively blocks development of COVID-19 in the rhesus disease model and accelerates the prospect of clinical studies with this effective antibody combination.


Subject(s)
COVID-19 , Viral Envelope Proteins , Animals , Antibodies, Neutralizing , Humans , Macaca mulatta , Membrane Glycoproteins , Neutralization Tests , SARS-CoV-2 , Spike Glycoprotein, Coronavirus
4.
Mol Cell ; 81(12): 2656-2668.e8, 2021 06 17.
Article in English | MEDLINE | ID: covidwho-1179919

ABSTRACT

A deficient interferon (IFN) response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been implicated as a determinant of severe coronavirus disease 2019 (COVID-19). To identify the molecular effectors that govern IFN control of SARS-CoV-2 infection, we conducted a large-scale gain-of-function analysis that evaluated the impact of human IFN-stimulated genes (ISGs) on viral replication. A limited subset of ISGs were found to control viral infection, including endosomal factors inhibiting viral entry, RNA binding proteins suppressing viral RNA synthesis, and a highly enriched cluster of endoplasmic reticulum (ER)/Golgi-resident ISGs inhibiting viral assembly/egress. These included broad-acting antiviral ISGs and eight ISGs that specifically inhibited SARS-CoV-2 and SARS-CoV-1 replication. Among the broad-acting ISGs was BST2/tetherin, which impeded viral release and is antagonized by SARS-CoV-2 Orf7a protein. Overall, these data illuminate a set of ISGs that underlie innate immune control of SARS-CoV-2/SARS-CoV-1 infection, which will facilitate the understanding of host determinants that impact disease severity and offer potential therapeutic strategies for COVID-19.


Subject(s)
Antigens, CD/genetics , Host-Pathogen Interactions/genetics , Interferon Regulatory Factors/genetics , Interferon Type I/genetics , SARS-CoV-2/genetics , Viral Proteins/genetics , Animals , Antigens, CD/chemistry , Antigens, CD/immunology , Binding Sites , Cell Line, Tumor , Chlorocebus aethiops , Endoplasmic Reticulum/genetics , Endoplasmic Reticulum/immunology , Endoplasmic Reticulum/virology , GPI-Linked Proteins/chemistry , GPI-Linked Proteins/genetics , GPI-Linked Proteins/immunology , Gene Expression Regulation , Golgi Apparatus/genetics , Golgi Apparatus/immunology , Golgi Apparatus/virology , HEK293 Cells , Host-Pathogen Interactions/immunology , Humans , Immunity, Innate , Interferon Regulatory Factors/classification , Interferon Regulatory Factors/immunology , Interferon Type I/immunology , Molecular Docking Simulation , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , SARS-CoV-2/immunology , Signal Transduction , Vero Cells , Viral Proteins/chemistry , Viral Proteins/immunology , Virus Internalization , Virus Release/genetics , Virus Release/immunology , Virus Replication/genetics , Virus Replication/immunology
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