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1.
Viruses ; 14(6):1126, 2022.
Article in English | MDPI | ID: covidwho-1857390

ABSTRACT

Without sufficient herd immunity through either vaccination or natural infection, the coronavirus disease 2019 pandemic is unlikely to be controlled. Waning immunity with the currently approved vaccines suggests the need to evaluate vaccines causing the induction of long-term responses. Here, we report the immunogenicity and efficacy of our adjuvanted single-dose Rabies-vectored SARS-CoV-2 S1 vaccine, CORAVAX, in hamsters. CORAVAX induces high SARS-CoV-2 S1-specific and virus-neutralizing antibodies (VNAs) that prevent weight loss, viral loads, disease, lung inflammation, and the cytokine storm in hamsters. We also observed high Rabies VNA titers. In summary, CORAVAX is a promising dual-antigen vaccine candidate for clinical evaluation against SARS-CoV-2 and Rabies virus.

2.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-329557

ABSTRACT

Without sufficient herd immunity through either vaccination or natural infection, the Coronavirus Disease 2019 pandemic is unlikely to be controlled. Waning immunity with the currently approved vaccines suggests the need to evaluate vaccines causing the induction of long-term responses. Here we report the immunogenicity and efficacy of our adjuvanted single-dose Rabies vectored SARS CoV-2 S1 vaccine, CORAVAX, in hamsters. CORAVAX induces high SARS CoV-2 S1 specific and virus-neutralizing antibodies (VNA) that prevent weight loss, viral loads, disease, lung inflammation, and the cytokine storm in hamsters. We also observed high Rabies VNA titers. In summary, CORAVAX is a promising dual antigen vaccine candidate for clinical evaluation against SARS CoV-2 and Rabies virus.

3.
PLoS Pathog ; 18(1): e1010255, 2022 01.
Article in English | MEDLINE | ID: covidwho-1649753

ABSTRACT

Nucleoside modified mRNA combined with Acuitas Therapeutics' lipid nanoparticles (LNPs) has been shown to support robust humoral immune responses in many preclinical animal vaccine studies and later in humans with the SARS-CoV-2 vaccination. We recently showed that this platform is highly inflammatory due to the LNPs' ionizable lipid component. The inflammatory property is key to support the development of potent humoral immune responses. However, the mechanism by which this platform drives T follicular helper (Tfh) cells and humoral immune responses remains unknown. Here we show that lack of Langerhans cells or cDC1s neither significantly affected the induction of PR8 HA and SARS-CoV-2 RBD-specific Tfh cells and humoral immune responses, nor susceptibility towards the lethal challenge of influenza and SARS-CoV-2. However, the combined deletion of these two DC subsets led to a significant decrease in the induction of PR8 HA and SARS-CoV-2 RBD-specific Tfh cell and humoral immune responses. Despite these observed defects, these mice remained protected from lethal influenza and SARS-CoV-2 challenges. We further found that IL-6, unlike neutrophils, was required to generate normal Tfh cells and antibody responses, but not for protection from influenza challenge. In summary, here we bring evidence that the mRNA-LNP platform can support the induction of protective immune responses in the absence of certain innate immune cells and cytokines.


Subject(s)
COVID-19 Vaccines/immunology , Dendritic Cells/immunology , Influenza Vaccines/immunology , Langerhans Cells/immunology , Liposomes/immunology , Vaccines, Synthetic/immunology , /immunology , Animals , COVID-19/immunology , Mice , Nanoparticles , Orthomyxoviridae Infections/immunology , SARS-CoV-2/immunology
4.
Proc Natl Acad Sci U S A ; 118(42)2021 10 19.
Article in English | MEDLINE | ID: covidwho-1447424

ABSTRACT

The coronaviruses responsible for severe acute respiratory syndrome (SARS-CoV), COVID-19 (SARS-CoV-2), Middle East respiratory syndrome-CoV, and other coronavirus infections express a nucleocapsid protein (N) that is essential for viral replication, transcription, and virion assembly. Phosphorylation of N from SARS-CoV by glycogen synthase kinase 3 (GSK-3) is required for its function and inhibition of GSK-3 with lithium impairs N phosphorylation, viral transcription, and replication. Here we report that the SARS-CoV-2 N protein contains GSK-3 consensus sequences and that this motif is conserved in diverse coronaviruses, raising the possibility that SARS-CoV-2 may be sensitive to GSK-3 inhibitors, including lithium. We conducted a retrospective analysis of lithium use in patients from three major health systems who were PCR-tested for SARS-CoV-2. We found that patients taking lithium have a significantly reduced risk of COVID-19 (odds ratio = 0.51 [0.35-0.74], P = 0.005). We also show that the SARS-CoV-2 N protein is phosphorylated by GSK-3. Knockout of GSK3A and GSK3B demonstrates that GSK-3 is essential for N phosphorylation. Alternative GSK-3 inhibitors block N phosphorylation and impair replication in SARS-CoV-2 infected lung epithelial cells in a cell-type-dependent manner. Targeting GSK-3 may therefore provide an approach to treat COVID-19 and future coronavirus outbreaks.


Subject(s)
COVID-19/prevention & control , Coronavirus Nucleocapsid Proteins/metabolism , Glycogen Synthase Kinase 3/antagonists & inhibitors , Lithium Compounds/therapeutic use , Adult , Aged , Female , Glycogen Synthase Kinase 3/metabolism , HEK293 Cells , Humans , Lithium Compounds/pharmacology , Male , Middle Aged , Molecular Targeted Therapy , Phosphoproteins/metabolism , Phosphorylation/drug effects , Retrospective Studies
5.
PLoS One ; 16(6): e0253089, 2021.
Article in English | MEDLINE | ID: covidwho-1282298

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a devastating global pandemic, infecting over 43 million people and claiming over 1 million lives, with these numbers increasing daily. Therefore, there is urgent need to understand the molecular mechanisms governing SARS-CoV-2 pathogenesis, immune evasion, and disease progression. Here, we show that SARS-CoV-2 can block IRF3 and NF-κB activation early during virus infection. We also identify that the SARS-CoV-2 viral proteins NSP1 and NSP13 can block interferon activation via distinct mechanisms. NSP1 antagonizes interferon signaling by suppressing host mRNA translation, while NSP13 downregulates interferon and NF-κB promoter signaling by limiting TBK1 and IRF3 activation, as phospho-TBK1 and phospho-IRF3 protein levels are reduced with increasing levels of NSP13 protein expression. NSP13 can also reduce NF-κB activation by both limiting NF-κB phosphorylation and nuclear translocation. Last, we also show that NSP13 binds to TBK1 and downregulates IFIT1 protein expression. Collectively, these data illustrate that SARS-CoV-2 bypasses multiple innate immune activation pathways through distinct mechanisms.


Subject(s)
Adaptor Proteins, Signal Transducing/immunology , COVID-19/immunology , Cell Nucleus/immunology , Interferon Regulatory Factor-3/immunology , RNA-Binding Proteins/immunology , SARS-CoV-2/immunology , Signal Transduction/immunology , Viral Nonstructural Proteins/immunology , Active Transport, Cell Nucleus/genetics , Active Transport, Cell Nucleus/immunology , Adaptor Proteins, Signal Transducing/genetics , COVID-19/genetics , Cell Nucleus/genetics , HeLa Cells , Humans , Interferon Regulatory Factor-3/genetics , NF-kappa B/genetics , NF-kappa B/immunology , Phosphorylation/genetics , Phosphorylation/immunology , /immunology , RNA-Binding Proteins/genetics , SARS-CoV-2/genetics , Signal Transduction/genetics , Viral Nonstructural Proteins/genetics
6.
Sci Immunol ; 6(59)2021 05 18.
Article in English | MEDLINE | ID: covidwho-1234281

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a global pandemic, resulting millions of infections and deaths with few effective interventions available. Here, we demonstrate that SARS-CoV-2 evades interferon (IFN) activation in respiratory epithelial cells, resulting in a delayed response in bystander cells. Since pretreatment with IFNs can block viral infection, we reasoned that pharmacological activation of innate immune pathways could control SARS-CoV-2 infection. To identify potent antiviral innate immune agonists, we screened a panel of 75 microbial ligands that activate diverse signaling pathways and identified cyclic dinucleotides (CDNs), canonical STING agonists, as antiviral. Since CDNs have poor bioavailability, we tested the small molecule STING agonist diABZI, and found that it potently inhibits SARS-CoV-2 infection of diverse strains including variants of concern (B.1.351) by transiently stimulating IFN signaling. Importantly, diABZI restricts viral replication in primary human bronchial epithelial cells and in mice in vivo. Our study provides evidence that activation of STING may represent a promising therapeutic strategy to control SARS-CoV-2.


Subject(s)
Antiviral Agents/pharmacology , Benzimidazoles/pharmacology , COVID-19/prevention & control , Interferons/immunology , Membrane Proteins/agonists , Animals , Cell Line , Chlorocebus aethiops , Enzyme Activation/drug effects , Epithelial Cells/virology , Humans , Immune Evasion/immunology , Immunity, Innate/drug effects , Immunity, Innate/immunology , Mice , Mice, Inbred C57BL , Mice, Transgenic , SARS-CoV-2/growth & development , SARS-CoV-2/immunology , Vero Cells , Virus Replication/drug effects
7.
Cell Rep ; 35(1): 108959, 2021 04 06.
Article in English | MEDLINE | ID: covidwho-1163484

ABSTRACT

There is an urgent need for antivirals to treat the newly emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). To identify new candidates, we screen a repurposing library of ∼3,000 drugs. Screening in Vero cells finds few antivirals, while screening in human Huh7.5 cells validates 23 diverse antiviral drugs. Extending our studies to lung epithelial cells, we find that there are major differences in drug sensitivity and entry pathways used by SARS-CoV-2 in these cells. Entry in lung epithelial Calu-3 cells is pH independent and requires TMPRSS2, while entry in Vero and Huh7.5 cells requires low pH and triggering by acid-dependent endosomal proteases. Moreover, we find nine drugs are antiviral in respiratory cells, seven of which have been used in humans, and three are US Food and Drug Administration (FDA) approved, including cyclosporine. We find that the antiviral activity of cyclosporine is targeting Cyclophilin rather than calcineurin, revealing essential host targets that have the potential for rapid clinical implementation.


Subject(s)
COVID-19/drug therapy , Cyclosporine/pharmacology , Drug Repositioning , Epithelial Cells/metabolism , Lung/metabolism , SARS-CoV-2/metabolism , Animals , COVID-19/metabolism , COVID-19/pathology , Chlorocebus aethiops , Epithelial Cells/pathology , Epithelial Cells/virology , Humans , Lung/pathology , Lung/virology , Serine Endopeptidases/metabolism , United States , United States Food and Drug Administration , Vero Cells
8.
Cell ; 184(7): 1858-1864.e10, 2021 04 01.
Article in English | MEDLINE | ID: covidwho-1071140

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has rapidly spread within the human population. Although SARS-CoV-2 is a novel coronavirus, most humans had been previously exposed to other antigenically distinct common seasonal human coronaviruses (hCoVs) before the coronavirus disease 2019 (COVID-19) pandemic. Here, we quantified levels of SARS-CoV-2-reactive antibodies and hCoV-reactive antibodies in serum samples collected from 431 humans before the COVID-19 pandemic. We then quantified pre-pandemic antibody levels in serum from a separate cohort of 251 individuals who became PCR-confirmed infected with SARS-CoV-2. Finally, we longitudinally measured hCoV and SARS-CoV-2 antibodies in the serum of hospitalized COVID-19 patients. Our studies indicate that most individuals possessed hCoV-reactive antibodies before the COVID-19 pandemic. We determined that ∼20% of these individuals possessed non-neutralizing antibodies that cross-reacted with SARS-CoV-2 spike and nucleocapsid proteins. These antibodies were not associated with protection against SARS-CoV-2 infections or hospitalizations, but they were boosted upon SARS-CoV-2 infection.


Subject(s)
Alphacoronavirus/immunology , Antibodies, Viral , Betacoronavirus/immunology , COVID-19/immunology , Adolescent , Adult , Animals , Antibodies, Viral/blood , Antibodies, Viral/immunology , COVID-19 Serological Testing , Child , Child, Preschool , Chlorocebus aethiops , Cross Protection , Cross Reactions , Disease Susceptibility , HEK293 Cells , Humans , Infant , Infant, Newborn , Vero Cells
9.
Science ; 369(6508)2020 09 04.
Article in English | MEDLINE | ID: covidwho-981641

ABSTRACT

Coronavirus disease 2019 (COVID-19) is currently a global pandemic, but human immune responses to the virus remain poorly understood. We used high-dimensional cytometry to analyze 125 COVID-19 patients and compare them with recovered and healthy individuals. Integrated analysis of ~200 immune and ~50 clinical features revealed activation of T cell and B cell subsets in a proportion of patients. A subgroup of patients had T cell activation characteristic of acute viral infection and plasmablast responses reaching >30% of circulating B cells. However, another subgroup had lymphocyte activation comparable with that in uninfected individuals. Stable versus dynamic immunological signatures were identified and linked to trajectories of disease severity change. Our analyses identified three immunotypes associated with poor clinical trajectories versus improving health. These immunotypes may have implications for the design of therapeutics and vaccines for COVID-19.


Subject(s)
B-Lymphocytes/immunology , Betacoronavirus/immunology , Coronavirus Infections/immunology , Pneumonia, Viral/immunology , T-Lymphocytes/immunology , Adaptive Immunity , Adult , Aged , Aged, 80 and over , Antibodies, Viral/blood , B-Lymphocyte Subsets/immunology , CD4-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/immunology , COVID-19 , Cytokines/blood , Female , Humans , Immunologic Memory , Lymphocyte Activation , Male , Middle Aged , Pandemics , Plasma Cells/immunology , SARS-CoV-2 , Severity of Illness Index , T-Lymphocyte Subsets/immunology , T-Lymphocytes, Helper-Inducer/immunology , Time Factors , Young Adult
10.
NPJ Vaccines ; 5: 98, 2020.
Article in English | MEDLINE | ID: covidwho-882900

ABSTRACT

The recently emerged coronavirus SARS-CoV-2, the causative agent of COVID-19, is rapidly spreading in the world. The exponentially expanding threat of SARS-CoV-2 to global health highlights the urgent need for a vaccine. Herein we show the rapid development of a novel, highly efficient, and safe COVID-19 vaccine using a rabies virus-based vector that has proven to be an efficient vaccine against several emerging infectious diseases. This study reports that both a live and an inactivated rabies virus containing the SARS-CoV-2 spike S1 protein induces potent virus-neutralizing antibodies at much higher levels than seen in the sera of convalescent patients. In summary, the results provided here warrant further development of this safe and established vaccine platform against COVID-19.

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