Your browser doesn't support javascript.
Show: 20 | 50 | 100
Results 1 - 9 de 9
Filter
1.
EuropePMC; 2021.
Preprint in English | EuropePMC | ID: ppcovidwho-312737

ABSTRACT

The SARS-CoV-2 virus has had a major impact on global human health. During the spread of SARS-CoV-2, weakened host immunity and the use of vaccines with low efficacy may result in the development of more virulent strains or strains with resistance to existing vaccines and antibodies. The prevalence of SARS-CoV-2 mutant strains differs among regions, and this variation may affect the effectiveness of vaccines. In this study, an epidemiological investigation of SARS-CoV-2 in Portugal was performed, and the VSV-ΔG-G* pseudovirus system was used to construct 12 S protein epidemic mutants, D614G, A222V+D614G, B.1.1.7, S477N+D614G, P1162R+D614G+A222V, D839Y+D614G, L176F+D614G, B.1.1.7+L216F, B.1.1.7+M740V, B.1.258, B.1.258+L1063F, and B.1.258+N751Y.The mutant pseudoviruses were used to infect four susceptible cell lines (i.e., Huh7, hACE2-293T, Vero, and LLC-MK2) and 14 cell lines overexpressing ACE2 from different species. Mutant strains did not show increased infectivity or cross-species transmission. Neutralization activity was evaluated using the newly constructed pseudoviruses, mouse serum, and 11 monoclonal antibodies. The neutralizing activity in immunized mouse serum was not significantly reduced for the mutant strains. Additionally, mutant strains in Portugal showed escape from 9 of 11 monoclonal antibodies. Neutralization resistance was mainly caused by the S477N, N439K, and N501Y mutations in the Spike receptor binding domain. These findings emphasize the importance of SARS-CoV-2 mutation tracking in different regions for epidemic prevention and control.

2.
Arch Virol ; 167(2): 459-470, 2022 Feb.
Article in English | MEDLINE | ID: covidwho-1653515

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has had a major impact on global human health. During the spread of SARS-CoV-2, weakened host immunity and the use of vaccines with low efficacy may result in the development of more-virulent strains or strains with resistance to existing vaccines and antibodies. The prevalence of SARS-CoV-2 mutant strains differs between regions, and this variation may have an impact on the effectiveness of vaccines. In this study, an epidemiological investigation of SARS-CoV-2 in Portugal was performed, and the VSV-ΔG-G* pseudovirus system was used to construct 12 spike protein epidemic mutants, D614G, A222V+D614G, B.1.1.7, S477N+D614G, P1162R+D614G+A222V, D839Y+D614G, L176F+D614G, B.1.1.7+L216F, B.1.1.7+M740V, B.1.258, B.1.258+L1063F, and B.1.258+N751Y. The mutant pseudoviruses were used to infect four susceptible cell lines (Huh7, hACE2-293T-293T, Vero, and LLC-MK2) and 14 cell lines overexpressing ACE2 from different species. Mutant strains did not show increased infectivity or cross-species transmission. Neutralization activity against these pseudoviruses was evaluated using mouse serum and 11 monoclonal antibodies. The neutralizing activity of immunized mouse serum was not significantly reduced with the mutant strains, but the mutant strains from Portugal could evade nine of the 11 monoclonal antibodies tested. Neutralization resistance was mainly caused by the mutations S477N, N439K, and N501Y in the spike-receptor binding domain. These findings emphasize the importance of SARS-CoV-2 mutation tracking in different regions for epidemic prevention and control.


Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Antibodies, Neutralizing , Humans , Mice , Mutation , Portugal/epidemiology , Spike Glycoprotein, Coronavirus/genetics
4.
Zhongguo Bingdubing Zazhi = Chinese Journal of Viral Diseases ; - (3):209, 2021.
Article in English | ProQuest Central | ID: covidwho-1329332

ABSTRACT

Most viruses require their glycoproteins to be hydrolyzed in order to enter host cells.In some cases, the severability of viral glycoproteins is a determinant of their virulence.These viral glycoproteins can be cleaved by one or more proteases in host cells with furin as the common one.Furin further promotes viral infection by identifying specific amino acid sequences in glycoprotein precursors.Morever, furin plays a critical role in the infections of many viruses including human immunodeficiency virus, flavivirus, filamentavirus and coronavirus, and is considered as a promising drug treatment and prevention target.In this review, we summarize the biological background of furin and its hydrolysis function to viral glycoproteins.

5.
Bioorg Chem ; 115: 105196, 2021 10.
Article in English | MEDLINE | ID: covidwho-1322004

ABSTRACT

So far, there is still no specific drug against COVID-19. Taking compound 1 with anti-EBOV activity as the lead, fifty-four 12N-substituted aloperine derivatives were synthesized and evaluated for the anti-SARS-CoV-2 activities using pseudotyped virus model. Among them, 8a exhibited the most potential effects against both pseudotyped and authentic SARS-CoV-2, as well as SARS-CoV and MERS-CoV, indicating a broad-spectrum anti-coronavirus profile. The mechanism study disclosed that 8a might block a late stage of viral entry, mainly via inhibiting host cathepsin B activity rather than directly targeting cathepsin B protein. Also, 8a could significantly reduce the release of multiple inflammatory cytokines in a time- and dose-dependent manner, such as IL-6, IL-1ß, IL-8 and MCP-1, the major contributors to cytokine storm. Therefore, 8a is a promising agent with the advantages of broad-spectrum anti-coronavirus and anti-cytokine effects, thus worthy of further investigation.


Subject(s)
Antiviral Agents/pharmacology , Piperidines/pharmacology , Quinolizidines/pharmacology , SARS-CoV-2/drug effects , Virus Internalization/drug effects , Animals , Antiviral Agents/chemical synthesis , Antiviral Agents/pharmacokinetics , Antiviral Agents/toxicity , Cathepsin B/antagonists & inhibitors , Chlorocebus aethiops , Cytokines/metabolism , HEK293 Cells , Humans , Male , Mice , Microbial Sensitivity Tests , Molecular Structure , Piperidines/chemical synthesis , Piperidines/pharmacokinetics , Piperidines/toxicity , Quinolizidines/chemical synthesis , Quinolizidines/pharmacokinetics , Quinolizidines/toxicity , Rats, Sprague-Dawley , Structure-Activity Relationship , Vero Cells
6.
Signal Transduct Target Ther ; 6(1): 134, 2021 03 27.
Article in English | MEDLINE | ID: covidwho-1152831

ABSTRACT

To discover new drugs to combat COVID-19, an understanding of the molecular basis of SARS-CoV-2 infection is urgently needed. Here, for the first time, we report the crucial role of cathepsin L (CTSL) in patients with COVID-19. The circulating level of CTSL was elevated after SARS-CoV-2 infection and was positively correlated with disease course and severity. Correspondingly, SARS-CoV-2 pseudovirus infection increased CTSL expression in human cells in vitro and human ACE2 transgenic mice in vivo, while CTSL overexpression, in turn, enhanced pseudovirus infection in human cells. CTSL functionally cleaved the SARS-CoV-2 spike protein and enhanced virus entry, as evidenced by CTSL overexpression and knockdown in vitro and application of CTSL inhibitor drugs in vivo. Furthermore, amantadine, a licensed anti-influenza drug, significantly inhibited CTSL activity after SARS-CoV-2 pseudovirus infection and prevented infection both in vitro and in vivo. Therefore, CTSL is a promising target for new anti-COVID-19 drug development.


Subject(s)
Antiviral Agents/pharmacology , COVID-19/metabolism , Cathepsin L , Cysteine Proteinase Inhibitors/pharmacology , Drug Development , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/metabolism , Virus Internalization/drug effects , Adolescent , Adult , Aged , Animals , COVID-19/drug therapy , COVID-19/genetics , Cathepsin L/antagonists & inhibitors , Cathepsin L/genetics , Cathepsin L/metabolism , Female , Humans , Male , Mice , Mice, Transgenic , Middle Aged , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics
7.
2020.
Preprint | CAplus | ID: ppcovidwho-5353

ABSTRACT

A review. Transmembrane serine protein 2 (TMPRSS2) is a member of serine protease family on the surface of cell membrane. It mediates the hydrolysis of spike protein of coronavirus, and is necessary for coronavirus infection in host cells. This paper summarized the research progress of TMPRSS2 in recent years, including its gene composition, protein structure, expression distribution, and mol. biol. functions. It focused on the role of TMPRSS2 in virus infection on respiratory system, especially on coronavirus infection, and summarized the research progress of drugs in targeting on TMPRSS2, hoping to provide new directions and targets for the prevention and treatment of the novel coronavirus.

8.
Cell ; 182(5): 1271-1283.e16, 2020 09 03.
Article in English | MEDLINE | ID: covidwho-666099

ABSTRACT

There is an urgent need for vaccines against coronavirus disease 2019 (COVID-19) because of the ongoing SARS-CoV-2 pandemic. Among all approaches, a messenger RNA (mRNA)-based vaccine has emerged as a rapid and versatile platform to quickly respond to this challenge. Here, we developed a lipid nanoparticle-encapsulated mRNA (mRNA-LNP) encoding the receptor binding domain (RBD) of SARS-CoV-2 as a vaccine candidate (called ARCoV). Intramuscular immunization of ARCoV mRNA-LNP elicited robust neutralizing antibodies against SARS-CoV-2 as well as a Th1-biased cellular response in mice and non-human primates. Two doses of ARCoV immunization in mice conferred complete protection against the challenge of a SARS-CoV-2 mouse-adapted strain. Additionally, ARCoV is manufactured as a liquid formulation and can be stored at room temperature for at least 1 week. ARCoV is currently being evaluated in phase 1 clinical trials.


Subject(s)
RNA, Messenger/genetics , RNA, Viral/genetics , Vaccines, Synthetic/immunology , Viral Vaccines/immunology , Animals , Antibodies, Neutralizing/immunology , Binding Sites , COVID-19 Vaccines , Chlorocebus aethiops , Coronavirus Infections/genetics , Coronavirus Infections/immunology , Coronavirus Infections/prevention & control , Female , HEK293 Cells , HeLa Cells , Humans , Immunogenicity, Vaccine , Injections, Intramuscular , Macaca fascicularis , Male , Mice , Mice, Inbred ICR , Nanoparticles/chemistry , RNA, Messenger/metabolism , RNA, Viral/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/metabolism , Th1 Cells/immunology , Vaccine Potency , Vaccines, Synthetic/administration & dosage , Vaccines, Synthetic/genetics , Vero Cells , Viral Vaccines/administration & dosage , Viral Vaccines/genetics
9.
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
SELECTION OF CITATIONS
SEARCH DETAIL