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1.
Molecules ; 27(3)2022 Jan 21.
Article in English | MEDLINE | ID: covidwho-1649980

ABSTRACT

COVID-19 has spread around the world and caused serious public health and social problems. Although several vaccines have been authorized for emergency use, new effective antiviral drugs are still needed. Some repurposed drugs including Chloroquine, Hydroxychloroquine and Remdesivir were immediately used to treat COVID-19 after the pandemic. However, the therapeutic effects of these drugs have not been fully demonstrated in clinical studies. In this paper, we found an antimalarial drug, Naphthoquine, showed good broad-spectrum anti-coronavirus activity. Naphthoquineinhibited HCoV-229E, HCoV-OC43 and SARS-CoV-2 replication in vitro, with IC50 = 2.05 ± 1.44 µM, 5.83 ± 0.74 µM, and 2.01 ± 0.38 µM, respectively. Time-of-addition assay was also performed to explore at which stage Naphthoquine functions during SARS-CoV-2 replication. The results suggested that Naphthoquine may influence virus entry and post-entry replication. Considering the safety of Naphthoquine was even better than that of Chloroquine, we think Naphthoquine has the potential to be used as a broad-spectrum drug for coronavirus infection.


Subject(s)
1-Naphthylamine/analogs & derivatives , Aminoquinolines/pharmacology , Antiviral Agents/pharmacology , Coronavirus/drug effects , SARS-CoV-2/drug effects , 1-Naphthylamine/pharmacology , Animals , Cell Line , Chlorocebus aethiops , Coronavirus 229E, Human/drug effects , Coronavirus NL63, Human/drug effects , Coronavirus OC43, Human/drug effects , Humans , In Vitro Techniques , Vero Cells , Virus Replication/drug effects
3.
Nat Commun ; 12(1): 5654, 2021 09 27.
Article in English | MEDLINE | ID: covidwho-1440471

ABSTRACT

There is an urgent need for animal models to study SARS-CoV-2 pathogenicity. Here, we generate and characterize a novel mouse-adapted SARS-CoV-2 strain, MASCp36, that causes severe respiratory symptoms, and mortality. Our model exhibits age- and gender-related mortality akin to severe COVID-19. Deep sequencing identified three amino acid substitutions, N501Y, Q493H, and K417N, at the receptor binding domain (RBD) of MASCp36, during in vivo passaging. All three RBD mutations significantly enhance binding affinity to its endogenous receptor, ACE2. Cryo-electron microscopy analysis of human ACE2 (hACE2), or mouse ACE2 (mACE2), in complex with the RBD of MASCp36, at 3.1 to 3.7 Å resolution, reveals the molecular basis for the receptor-binding switch. N501Y and Q493H enhance the binding affinity to hACE2, whereas triple mutations at N501Y/Q493H/K417N decrease affinity and reduce infectivity of MASCp36. Our study provides a platform for studying SARS-CoV-2 pathogenesis, and unveils the molecular mechanism for its rapid adaptation and evolution.


Subject(s)
COVID-19/diagnosis , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/metabolism , Amino Acid Substitution , Angiotensin-Converting Enzyme 2/metabolism , Animals , Binding Sites/genetics , COVID-19/mortality , COVID-19/virology , Disease Models, Animal , Female , Humans , Male , Mice , Protein Binding/genetics , Protein Domains/genetics , SARS-CoV-2/genetics , Severity of Illness Index , Spike Glycoprotein, Coronavirus/genetics
4.
Adv Mater ; 33(40): e2102528, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1358054

ABSTRACT

Dendritic cell (DC) vaccines are used for cancer and infectious diseases, albeit with limited efficacy. Modulating the formation of DC-T-cell synapses may greatly increase their efficacy. The effects of graphene oxide (GO) nanosheets on DCs and DC-T-cell synapse formation are evaluated. In particular, size-dependent interactions are observed between GO nanosheets and DCs. GOs with diameters of >1 µm (L-GOs) demonstrate strong adherence to the DC surface, inducing cytoskeletal reorganization via the RhoA-ROCK-MLC pathway, while relatively small GOs (≈500 nm) are predominantly internalized by DCs. Furthermore, L-GO treatment enhances DC-T-cell synapse formation via cytoskeleton-dependent membrane positioning of integrin ICAM-1. L-GO acts as a "nanozipper," facilitating the aggregation of DC-T-cell clusters to produce a stable microenvironment for T cell activation. Importantly, L-GO-adjuvanted DCs promote robust cytotoxic T cell immune responses against SARS-CoV-2 spike 1, leading to >99.7% viral RNA clearance in mice infected with a clinically isolated SARS-CoV-2 strain. These findings highlight the potential value of nanomaterials as DC vaccine adjuvants for modulating DC-T-cell synapse formation and provide a basis for the development of effective COVID-19 vaccines.


Subject(s)
Adjuvants, Immunologic/therapeutic use , COVID-19 Vaccines/therapeutic use , COVID-19/prevention & control , Dendritic Cells/immunology , Graphite/therapeutic use , Nanostructures/therapeutic use , Adjuvants, Immunologic/chemistry , Animals , COVID-19/immunology , COVID-19 Vaccines/immunology , Dendritic Cells/drug effects , Graphite/chemistry , Humans , Mice , Nanostructures/chemistry , SARS-CoV-2/immunology , T-Lymphocytes/drug effects , T-Lymphocytes/immunology
6.
Signal Transduct Target Ther ; 5(1): 283, 2020 12 04.
Article in English | MEDLINE | ID: covidwho-957563

ABSTRACT

In face of the everlasting battle toward COVID-19 and the rapid evolution of SARS-CoV-2, no specific and effective drugs for treating this disease have been reported until today. Angiotensin-converting enzyme 2 (ACE2), a receptor of SARS-CoV-2, mediates the virus infection by binding to spike protein. Although ACE2 is expressed in the lung, kidney, and intestine, its expressing levels are rather low, especially in the lung. Considering the great infectivity of COVID-19, we speculate that SARS-CoV-2 may depend on other routes to facilitate its infection. Here, we first discover an interaction between host cell receptor CD147 and SARS-CoV-2 spike protein. The loss of CD147 or blocking CD147 in Vero E6 and BEAS-2B cell lines by anti-CD147 antibody, Meplazumab, inhibits SARS-CoV-2 amplification. Expression of human CD147 allows virus entry into non-susceptible BHK-21 cells, which can be neutralized by CD147 extracellular fragment. Viral loads are detectable in the lungs of human CD147 (hCD147) mice infected with SARS-CoV-2, but not in those of virus-infected wild type mice. Interestingly, virions are observed in lymphocytes of lung tissue from a COVID-19 patient. Human T cells with a property of ACE2 natural deficiency can be infected with SARS-CoV-2 pseudovirus in a dose-dependent manner, which is specifically inhibited by Meplazumab. Furthermore, CD147 mediates virus entering host cells by endocytosis. Together, our study reveals a novel virus entry route, CD147-spike protein, which provides an important target for developing specific and effective drug against COVID-19.


Subject(s)
Basigin/genetics , COVID-19/genetics , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Animals , Basigin/immunology , COVID-19/immunology , COVID-19/pathology , COVID-19/virology , Host-Pathogen Interactions/immunology , Humans , Lung/immunology , Lung/pathology , Lung/virology , Mice , Pandemics , Protein Binding/immunology , Protein Domains/genetics , Protein Domains/immunology , SARS-CoV-2/pathogenicity , Spike Glycoprotein, Coronavirus/genetics , Virus Internalization
7.
Science ; 369(6511): 1603-1607, 2020 09 25.
Article in English | MEDLINE | ID: covidwho-690532

ABSTRACT

The ongoing coronavirus disease 2019 (COVID-19) pandemic has prioritized the development of small-animal models for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). We adapted a clinical isolate of SARS-CoV-2 by serial passaging in the respiratory tract of aged BALB/c mice. The resulting mouse-adapted strain at passage 6 (called MASCp6) showed increased infectivity in mouse lung and led to interstitial pneumonia and inflammatory responses in both young and aged mice after intranasal inoculation. Deep sequencing revealed a panel of adaptive mutations potentially associated with the increased virulence. In particular, the N501Y mutation is located at the receptor binding domain (RBD) of the spike protein. The protective efficacy of a recombinant RBD vaccine candidate was validated by using this model. Thus, this mouse-adapted strain and associated challenge model should be of value in evaluating vaccines and antivirals against SARS-CoV-2.


Subject(s)
Betacoronavirus/immunology , Coronavirus Infections/prevention & control , Disease Models, Animal , Mice , Pandemics/prevention & control , Pneumonia, Viral/prevention & control , Viral Vaccines/immunology , Administration, Intranasal , Angiotensin-Converting Enzyme 2 , Animals , Betacoronavirus/genetics , Betacoronavirus/pathogenicity , COVID-19 , COVID-19 Vaccines , Coronavirus Infections/immunology , Female , High-Throughput Nucleotide Sequencing , Humans , Immunogenicity, Vaccine , Lung/virology , Lung Diseases, Interstitial/virology , Mice, Inbred BALB C , Mice, Transgenic , Mutation , Peptidyl-Dipeptidase A/genetics , SARS-CoV-2 , Spike Glycoprotein, Coronavirus/genetics , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/immunology , Viral Vaccines/administration & dosage , Virulence/genetics
8.
Cell Host Microbe ; 28(1): 124-133.e4, 2020 07 08.
Article in English | MEDLINE | ID: covidwho-378130

ABSTRACT

Since December 2019, a novel coronavirus SARS-CoV-2 has emerged and rapidly spread throughout the world, resulting in a global public health emergency. The lack of vaccine and antivirals has brought an urgent need for an animal model. Human angiotensin-converting enzyme II (ACE2) has been identified as a functional receptor for SARS-CoV-2. In this study, we generated a mouse model expressing human ACE2 (hACE2) by using CRISPR/Cas9 knockin technology. In comparison with wild-type C57BL/6 mice, both young and aged hACE2 mice sustained high viral loads in lung, trachea, and brain upon intranasal infection. Although fatalities were not observed, interstitial pneumonia and elevated cytokines were seen in SARS-CoV-2 infected-aged hACE2 mice. Interestingly, intragastric inoculation of SARS-CoV-2 was seen to cause productive infection and lead to pulmonary pathological changes in hACE2 mice. Overall, this animal model described here provides a useful tool for studying SARS-CoV-2 transmission and pathogenesis and evaluating COVID-19 vaccines and therapeutics.


Subject(s)
Betacoronavirus/physiology , Coronavirus Infections , Disease Models, Animal , Mice, Inbred C57BL , Pandemics , Pneumonia, Viral , Aging , Angiotensin-Converting Enzyme 2 , Animals , Brain/virology , COVID-19 , CRISPR-Cas Systems , Coronavirus Infections/pathology , Coronavirus Infections/virology , Cytokines/blood , Gene Knock-In Techniques , Lung/pathology , Lung/virology , Lung Diseases, Interstitial/pathology , Nose/virology , Peptidyl-Dipeptidase A/genetics , Peptidyl-Dipeptidase A/metabolism , Pneumonia, Viral/pathology , Pneumonia, Viral/virology , RNA, Viral/analysis , SARS-CoV-2 , Stomach/virology , Trachea/virology , Viral Load , Virus Replication
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