ABSTRACT
The Omicron variant is sweeping the world, which displays striking immune escape potential through mutations at key antigenic sites on the spike protein, making broad-spectrum SARS-CoV-2 prevention or therapeutical strategies urgently needed. Previously, we have reported a hACE2-targeting neutralizing antibody 3E8, which could efficiently block both prototype SARS-CoV-2 and Delta variant infections in prophylactic mouse models, having the potential of broad-spectrum to prevent SARS-CoV-2. However, preparation of monoclonal neutralizing antibodies is severely limited by the time-consuming process and the relative high cost. Here, we utilized a modified VEEV replicon with two subgenomic (sg) promoters engineered to express the light and heavy chains of the 3E8 mAb. The feasibility and protective efficacy of replicating mRNA encoding 3E8 against Omicron infection in the hamster were demonstrated through the lung targeting delivery with the help of VEEV-VRP. Overall, we developed a safe and cost-effective platform of broad-spectrum to prevent SARS-CoV-2 infection.
Subject(s)
COVID-19 , SARS-CoV-2 , Animals , Cricetinae , Mice , SARS-CoV-2/genetics , COVID-19/prevention & control , Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing , RNA, Messenger , Spike Glycoprotein, Coronavirus/genetics , Antibodies, ViralSubject(s)
Alphavirus , COVID-19 , Humans , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , RepliconABSTRACT
COVID-19 caused by SARS-CoV-2 has posed a significant threat to global public health since its outbreak in late 2019. Although there are a few drugs approved for clinical treatment to combat SARS-CoV-2 infection currently, the severity of the ongoing global pandemic still urges the efforts to discover new antiviral compounds. As the viral spike (S) protein plays a key role in mediating virus entry, it becomes a potential target for the design of antiviral drugs against COVID-19. Here, we tested the antiviral activity of berbamine hydrochloride, a bis-benzylisoquinoline alkaloid, against SARS-CoV-2 infection. We found that berbamine hydrochloride could efficiently inhibit SARS-CoV-2 infection in different cell lines. Further experiments showed berbamine hydrochloride inhibits SARS-CoV-2 infection by targeting the viral entry into host cells. Moreover, berbamine hydrochloride and other bis-benzylisoquinoline alkaloids could potently inhibit S-mediated cell-cell fusion. Furthermore, molecular docking results implied that the berbamine hydrochloride could bind to the post fusion core of SARS-CoV-2 S2 subunit. Therefore, berbamine hydrochloride may represent a potential efficient antiviral agent against SARS-CoV-2 infection.
Subject(s)
Benzylisoquinolines , COVID-19 Drug Treatment , Antiviral Agents/pharmacology , Benzylisoquinolines/pharmacology , Humans , Membrane Fusion , Molecular Docking Simulation , SARS-CoV-2 , Spike Glycoprotein, Coronavirus , Virus InternalizationABSTRACT
The lung is the prophylaxis target against SARS-CoV-2 infection, and neutralizing antibodies are a leading class of biological products against various infectious viral pathogen. In this study, we develop a safe and cost-effective platform to express neutralizing antibody in the lung with replicating mRNA basing on alphavirus replicon particle (VRP) delivery system, to prevent SARS-CoV-2 infections. First, a modified VEEV replicon with two subgenomic (sg) promoters was engineered to translate the light and heavy chains of antibody simultaneously, for expression and assembly of neutralizing anti-SARS-CoV-2 antibody CB6. Second, the feasibility and protective efficacy of replicating mRNA against SARS-CoV-2 infection were demonstrated through both in vitro and in vivo assays. The lung target delivery with the help of VRP system resulted in efficiently block SARS-CoV-2 infection with reducing viral titer and less tissue damage in the lung of mice. Overall, our data suggests that expressing neutralizing antibodies in the lungs with the help of self-replicating mRNA could potentially be a promising prophylaxis approach against SARS-CoV-2 infection.
Subject(s)
Alphavirus , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/therapy , Replicon , SARS-CoV-2/metabolism , Animals , Antibodies, Neutralizing/biosynthesis , Antibodies, Neutralizing/genetics , Antibodies, Viral/biosynthesis , Antibodies, Viral/genetics , COVID-19/genetics , COVID-19/metabolism , Chlorocebus aethiops , Cricetinae , Female , Mice , Mice, Inbred BALB C , RNA, Messenger/genetics , RNA, Messenger/metabolism , SARS-CoV-2/genetics , Vero CellsSubject(s)
Antiviral Agents/pharmacology , Betacoronavirus/drug effects , Cardiac Glycosides/pharmacology , Gene Expression Regulation/drug effects , Host-Pathogen Interactions/drug effects , Animals , Antiviral Agents/chemistry , Betacoronavirus/pathogenicity , Biological Products/chemistry , Biological Products/pharmacology , Bufanolides/chemistry , Bufanolides/pharmacology , COVID-19 , Cardiac Glycosides/chemistry , Cell Survival/drug effects , Chlorocebus aethiops , Chloroquine/chemistry , Chloroquine/pharmacology , Coronavirus Infections/drug therapy , Coronavirus Infections/virology , Digoxin/chemistry , Digoxin/pharmacology , High-Throughput Screening Assays , Host-Pathogen Interactions/genetics , Humans , Janus Kinases/antagonists & inhibitors , Janus Kinases/genetics , Janus Kinases/metabolism , Mitogen-Activated Protein Kinases/antagonists & inhibitors , Mitogen-Activated Protein Kinases/genetics , Mitogen-Activated Protein Kinases/metabolism , NF-E2-Related Factor 2/antagonists & inhibitors , NF-E2-Related Factor 2/genetics , NF-E2-Related Factor 2/metabolism , NF-kappa B/antagonists & inhibitors , NF-kappa B/genetics , NF-kappa B/metabolism , Pandemics , Phenanthrenes/chemistry , Phenanthrenes/pharmacology , Pneumonia, Viral/drug therapy , Pneumonia, Viral/virology , SARS-CoV-2 , Signal Transduction , Sodium-Potassium-Exchanging ATPase/antagonists & inhibitors , Sodium-Potassium-Exchanging ATPase/genetics , Sodium-Potassium-Exchanging ATPase/metabolism , Vero Cells , Virus Replication/drug effectsABSTRACT
The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus, which is highly pathogenic and classified as a biosafety level 3 (BSL-3) agent, has greatly threatened global health and efficacious antivirals are urgently needed. The high requirement of facilities to manipulate the live virus has limited the development of antiviral study. Here, we constructed a reporter replicon of SARS-CoV-2, which can be handled in a BSL-2 laboratory. The Renilla luciferase activity effectively reflected the transcription and replication levels of the replicon genome. We identified the suitability of the replicon in antiviral screening using the known inhibitors, and thus established the replicon-based high-throughput screening (HTS) assay for SARS-CoV-2. The application of the HTS assay was further validated using a few hit natural compounds, which were screened out in a SARS-CoV-2 induced cytopathic-effect-based HTS assay in our previous study. This replicon-based HTS assay will be a safe platform for SARS-CoV-2 antiviral screening in a BSL-2 laboratory without the live virus.