115 results on '"Nicolaescu V"'
Search Results
2. Some Aspects of Chronic Bronchitis in Romania
- Author
-
Racoveanu, Carmen, primary, Nicolaescu, V., additional, and Manicatide, and M., additional
- Full Text
- View/download PDF
3. A Double-Blind Trial between Tetracycline HCl and Guamecycline in Acute Exacerbations of Chronic Bronchitis
- Author
-
Nicolaescu, V., primary, Georgescu, Antigona, additional, Manicatide, M., additional, and Racoveanu, Carmen, additional
- Full Text
- View/download PDF
4. Smoking Habits in Romania.
- Author
-
RACOVEANU, CARMEN, TECULESCU, D., MANICATIDE, M., and NICOLAESCU, V.
- Abstract
The main aspects and consequences of tobacco use resulting from a series of field surveys in Romania are reviewed. The proportion of smokers in middle-aged adults is about 10 per cent for women and 40 to 50 per cent for men. Cigarettes are practically the only form of tobacco consumed—cigars are very rarely smoked and pipe-smoking accounts for less than 1 per cent of tobacco use. Less than 10 per cent of smokers use more than 25 cigarettes a day. Age at starting to smoke is low, with a quarter of smokers taking up the habit by the age of 15. Ninety per cent of the smokers admit to inhaling, and about half the men and nearly all the women smoke filter cigarettes. [ABSTRACT FROM PUBLISHER]
- Published
- 1975
- Full Text
- View/download PDF
5. β-Adrenergic Blockade with Practolol in Acetylcholine-Sensitive Asthma Patients.
- Author
-
Nicolaescu, V., Manicatide, M., and Stroescu, V.
- Published
- 1972
- Full Text
- View/download PDF
6. SINGLE VISIT ENDOVENOUS LASER TREATMENT AND TRIBUTARY PREOCEDURES FOR SYMPTOMATIC GREAT SAPHENOUS VARICOUS VEINS.
- Author
-
Duţă, C., Barjica, Dana, Hordovan, Eniko, Abdulah, S., Nicolaescu, V., and Medelean, P.
- Subjects
LASER endoscopy ,VARICOSE veins ,THERAPEUTICS - Abstract
An abstract of the article "Single Visit Endovenous Laser Treatment and Tributary Preocedures for Symptomatic Great Saphenous Varicous Veins," by C. Duţă, and colleagues is presented.
- Published
- 2015
- Full Text
- View/download PDF
7. Novel antibody language model accelerates IgG screening and design for broad-spectrum antiviral therapy.
- Author
-
Almubarak HF, Tan W, Hoffmann AD, Sun Y, Wei J, El-Shennawy L, Squires JR, Dashzeveg NK, Simonton B, Jia Y, Iyer R, Xu Y, Nicolaescu V, Elli D, Randall GC, Schipma MJ, Swaminathan S, Ison MG, Liu H, Fang D, and Shen Y
- Abstract
Therapeutic antibodies have become one of the most influential therapeutics in modern medicine to fight against infectious pathogens, cancer, and many other diseases. However, experimental screening for highly efficacious targeting antibodies is labor-intensive and of high cost, which is exacerbated by evolving antigen targets under selective pressure such as fast-mutating viral variants. As a proof-of-concept, we developed a machine learning-assisted antibody generation pipeline AbGen that greatly accelerates the screening and re-design of immunoglobulins G (IgGs) against a broad spectrum of SARS-CoV-2 coronavirus variant strains. Our AbGen centers around a novel antibody language model (AbLM) that is pretrained on 12 million generic protein domain sequences and fine-tuned on 4,000+ paired VH-VL sequences, with IgG-specific CDR-masking and VH-VL cross-attention. AbLM provides a latent space of IgG sequence embeddings for AbGen, including (a) landscapes of IgGs' activities in neutralizing the wild-type virus are analyzed through structure prediction for IgG and IgG-antigen (viral protein spike's receptor binding domain, RBD) interactions; and (b) landscapes of IgGs' susceptibility in neutralizing variant viruses are predicted through Gaussian process regression, despite that as few as 14 clinical antibodies' responses to variants of concern are available. The AbGen pipeline was applied to over 1300 IgG sequences we collected from RBD-binding B cells of convalescent patients. With experimental validations, AbGen efficiently prioritized IgG candidates against a broad spectrum of viral variants (wildtype, Delta, and Omicron), preventing the infection of host cells in vitro and hACE2 transgenic mice in vivo . Compared to other existing protein language models that require 10-100 times more model parameters, AbLM improved the precision from around 50% to 75% to predict IgGs with low variant susceptibility. Furthermore, AbGen enables structure-based computational protein redesign for selected IgG clones with single amino acid substitutions at the RBD-binding interface that doubled the IgG blockade efficacy for one of the severe, therapy-resistant strains - Delta (B.1.617). Our work expedites applications of artificial intelligence in antibody screen and re-design combining data-driven protein language models and Kriging for antibody sequence analysis and activity prediction, in synergy with physics-driven protein docking and design for antibody-antigen interface analyses and functional optimization., Competing Interests: Competing interest statement Northwestern University and H. L., D. F., L. E., A. D. H., and N. K. D. hold issued and/or provisional patents in IgG and exosome therapeutics. H.L., D. F., and A.D.H are scientific co-founders of ExoMira Medicine Inc.
- Published
- 2024
- Full Text
- View/download PDF
8. Soluble Angiotensin-Converting Enzyme 2 Protein Improves Survival and Lowers Viral Titers in Lethal Mouse Model of Severe Acute Respiratory Syndrome Coronavirus Type 2 Infection with the Delta Variant.
- Author
-
Cianfarini C, Hassler L, Wysocki J, Hassan A, Nicolaescu V, Elli D, Gula H, Ibrahim AM, Randall G, Henkin J, and Batlle D
- Subjects
- Humans, Mice, Animals, Peptidyl-Dipeptidase A metabolism, SARS-CoV-2 metabolism, Angiotensin-Converting Enzyme 2, COVID-19, gamma-Globulins, Melphalan
- Abstract
Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) utilizes angiotensin-converting enzyme 2 (ACE2) as its main receptor for cell entry. We bioengineered a soluble ACE2 protein termed ACE2 618-DDC-ABD that has increased binding to SARS-CoV-2 and prolonged duration of action. Here, we investigated the protective effect of this protein when administered intranasally to k18-hACE2 mice infected with the aggressive SARS-CoV-2 Delta variant. k18-hACE2 mice were infected with the SARS-CoV-2 Delta variant by inoculation of a lethal dose (2 × 10
4 PFU). ACE2 618-DDC-ABD (10 mg/kg) or PBS was administered intranasally six hours prior and 24 and 48 h post-viral inoculation. All animals in the PBS control group succumbed to the disease on day seven post-infection (0% survival), whereas, in contrast, there was only one casualty in the group that received ACE2 618-DDC-ABD (90% survival). Mice in the ACE2 618-DDC-ABD group had minimal disease as assessed using a clinical score and stable weight, and both brain and lung viral titers were markedly reduced. These findings demonstrate the efficacy of a bioengineered soluble ACE2 decoy with an extended duration of action in protecting against the aggressive Delta SARS-CoV-2 variant. Together with previous work, these findings underline the universal protective potential against current and future emerging SARS-CoV-2 variants.- Published
- 2024
- Full Text
- View/download PDF
9. Mycolactone: A Broad Spectrum Multitarget Antiviral Active in the Picomolar Range for COVID-19 Prevention and Cure.
- Author
-
Asiedu SO, Gupta Y, Nicolaescu V, Gula H, Caulfield TR, Durvasula R, Kempaiah P, Kwofie SK, and Wilson MD
- Subjects
- Humans, SARS-CoV-2, Antiviral Agents pharmacology, HEK293 Cells, COVID-19
- Abstract
We have previously shown computationally that Mycolactone (MLN), a toxin produced by Mycobacterium ulcerans, strongly binds to Munc18b and other proteins, presumably blocking degranulation and exocytosis of blood platelets and mast cells. We investigated the effect of MLN on endocytosis using similar approaches, and it bound strongly to the N-terminal of the clathrin protein and a novel SARS-CoV-2 fusion protein. Experimentally, we found 100% inhibition up to 60 nM and 84% average inhibition at 30 nM in SARS-CoV-2 live viral assays. MLN was also 10× more potent than remdesivir and molnupiravir. MLN's toxicity against human alveolar cell line A549, immortalized human fetal renal cell line HEK293, and human hepatoma cell line Huh7.1 were 17.12%, 40.30%, and 36.25%, respectively. The cytotoxicity IC
50 breakpoint ratio versus anti-SARS-CoV-2 activity was more than 65-fold. The IC50 values against the alpha, delta, and Omicron variants were all below 0.020 µM, and 134.6 nM of MLN had 100% inhibition in an entry and spread assays. MLN is eclectic in its actions through its binding to Sec61, AT2R, and the novel fusion protein, making it a good drug candidate for treating and preventing COVID-19 and other similarly transmitted enveloped viruses and pathogens.- Published
- 2023
- Full Text
- View/download PDF
10. Intranasal soluble ACE2 improves survival and prevents brain SARS-CoV-2 infection.
- Author
-
Hassler L, Wysocki J, Ahrendsen JT, Ye M, Gelarden I, Nicolaescu V, Tomatsidou A, Gula H, Cianfarini C, Forster P, Khurram N, Singer BD, Randall G, Missiakas D, Henkin J, and Batlle D
- Subjects
- Animals, Mice, SARS-CoV-2, Brain, Angiotensin-Converting Enzyme 2, COVID-19
- Abstract
A soluble ACE2 protein bioengineered for long duration of action and high affinity to SARS-CoV-2 was administered either intranasally (IN) or intraperitoneally (IP) to SARS-CoV-2-inoculated k18hACE2 mice. This decoy protein (ACE2 618-DDC-ABD) was given either IN or IP, pre- and post-inoculation, or IN, IP, or IN + IP but only post-inoculation. Survival by day 5 was 0% in untreated mice, 40% in the IP-pre, and 90% in the IN-pre group. In the IN-pre group, brain histopathology was essentially normal and lung histopathology significantly improved. Consistent with this, brain SARS-CoV-2 titers were undetectable and lung titers reduced in the IN-pre group. When ACE2 618-DDC-ABD was administered only post-inoculation, survival was 30% in the IN + IP, 20% in the IN, and 20% in the IP group. We conclude that ACE2 618-DDC-ABD results in markedly improved survival and provides organ protection when given intranasally as compared with when given either systemically or after viral inoculation, and that lowering brain titers is a critical determinant of survival and organ protection., (© 2023 Hassler et al.)
- Published
- 2023
- Full Text
- View/download PDF
11. In Silico Binding of 2-Aminocyclobutanones to SARS-CoV-2 Nsp13 Helicase and Demonstration of Antiviral Activity.
- Author
-
Mohammad TSH, Gupta Y, Reidl CT, Nicolaescu V, Gula H, Durvasula R, Kempaiah P, and Becker DP
- Subjects
- Humans, Antiviral Agents pharmacology, Antiviral Agents chemistry, RNA Helicases metabolism, Molecular Docking Simulation, Viral Nonstructural Proteins metabolism, DNA Helicases metabolism, SARS-CoV-2 metabolism, COVID-19
- Abstract
The landscape of viral strains and lineages of SARS-CoV-2 keeps changing and is currently dominated by Delta and Omicron variants. Members of the latest Omicron variants, including BA.1, are showing a high level of immune evasion, and Omicron has become a prominent variant circulating globally. In our search for versatile medicinal chemistry scaffolds, we prepared a library of substituted ɑ-aminocyclobutanones from an ɑ-aminocyclobutanone synthon ( 11 ). We performed an in silico screen of this actual chemical library as well as other virtual 2-aminocyclobutanone analogs against seven SARS-CoV-2 nonstructural proteins to identify potential drug leads against SARS-CoV-2, and more broadly against coronavirus antiviral targets. Several of these analogs were initially identified as in silico hits against SARS-CoV-2 nonstructural protein 13 (Nsp13) helicase through molecular docking and dynamics simulations. Antiviral activity of the original hits as well as ɑ-aminocyclobutanone analogs that were predicted to bind more tightly to SARS-CoV-2 Nsp13 helicase are reported. We now report cyclobutanone derivatives that exhibit anti-SARS-CoV-2 activity. Furthermore, the Nsp13 helicase enzyme has been the target of relatively few target-based drug discovery efforts, in part due to a very late release of a high-resolution structure accompanied by a limited understanding of its protein biochemistry. In general, antiviral agents initially efficacious against wild-type SARS-CoV-2 strains have lower activities against variants due to heavy viral loads and greater turnover rates, but the inhibitors we are reporting have higher activities against the later variants than the wild-type (10-20X). We speculate this could be due to Nsp13 helicase being a critical bottleneck in faster replication rates of the new variants, so targeting this enzyme affects these variants to an even greater extent. This work calls attention to cyclobutanones as a useful medicinal chemistry scaffold, and the need for additional focus on the discovery of Nsp13 helicase inhibitors to combat the aggressive and immune-evading variants of concern (VOCs).
- Published
- 2023
- Full Text
- View/download PDF
12. A comprehensive SARS-CoV-2-human protein-protein interactome reveals COVID-19 pathobiology and potential host therapeutic targets.
- Author
-
Zhou Y, Liu Y, Gupta S, Paramo MI, Hou Y, Mao C, Luo Y, Judd J, Wierbowski S, Bertolotti M, Nerkar M, Jehi L, Drayman N, Nicolaescu V, Gula H, Tay S, Randall G, Wang P, Lis JT, Feschotte C, Erzurum SC, Cheng F, and Yu H
- Subjects
- Humans, Cell Line, Gene Expression Regulation, SARS-CoV-2 genetics, Viral Proteins metabolism, COVID-19, Protein Interaction Mapping
- Abstract
Studying viral-host protein-protein interactions can facilitate the discovery of therapies for viral infection. We use high-throughput yeast two-hybrid experiments and mass spectrometry to generate a comprehensive SARS-CoV-2-human protein-protein interactome network consisting of 739 high-confidence binary and co-complex interactions, validating 218 known SARS-CoV-2 host factors and revealing 361 novel ones. Our results show the highest overlap of interaction partners between published datasets and of genes differentially expressed in samples from COVID-19 patients. We identify an interaction between the viral protein ORF3a and the human transcription factor ZNF579, illustrating a direct viral impact on host transcription. We perform network-based screens of >2,900 FDA-approved or investigational drugs and identify 23 with significant network proximity to SARS-CoV-2 host factors. One of these drugs, carvedilol, shows clinical benefits for COVID-19 patients in an electronic health records analysis and antiviral properties in a human lung cell line infected with SARS-CoV-2. Our study demonstrates the value of network systems biology to understand human-virus interactions and provides hits for further research on COVID-19 therapeutics., (© 2022. The Author(s), under exclusive licence to Springer Nature America, Inc.)
- Published
- 2023
- Full Text
- View/download PDF
13. Superiority of intranasal over systemic administration of bioengineered soluble ACE2 for survival and brain protection against SARS-CoV-2 infection.
- Author
-
Hassler L, Wysocki J, Ahrendsen JT, Ye M, Gelarden I, Nicolaescu V, Tomatsidou A, Gula H, Cianfarini C, Khurram N, Kanwar Y, Singer BD, Randall G, Missiakas D, Henkin J, and Batlle D
- Abstract
The present study was designed to investigate the effects of a soluble ACE2 protein termed ACE2 618-DDC-ABD, bioengineered to have long duration of action and high binding affinity to SARS-CoV-2, when administered either intranasally (IN) or intraperitoneally (IP) and before or after SARS-CoV-2 inoculation. K18hACE2 mice permissive for SARS-CoV-2 infection were inoculated with 2Ã-10
4 PFU wildtype SARS-CoV-2. In one protocol, ACE2 618-DDC-ABD was given either IN or IP, pre- and post-viral inoculation. In a second protocol, ACE2 618-DDC-ABD was given either IN, IP or IN+IP but only post-viral inoculation. In addition, A549 and Vero E6 cells were used to test neutralization of SARS-CoV-2 variants by ACE2 618-DDC-ABD at different concentrations. Survival by day 5 was 0% in infected untreated mice, and 40% in mice from the ACE2 618-DDC-ABD IP-pre treated group. By contrast, in the IN-pre group survival was 90%, histopathology of brain and kidney was essentially normal and markedly improved in the lungs. When ACE2 618-DDC-ABD was administered only post viral inoculation, survival was 30% in the IN+IP group, 20% in the IN and 0% in the IP group. Brain SARS-CoV-2 titers were high in all groups except for the IN-pre group where titers were undetectable in all mice. In cells permissive for SARS-CoV-2 infection, ACE2 618-DDC-ABD neutralized wildtype SARS-CoV-2 at high concentrations, whereas much lower concentrations neutralized omicron BA. 1. We conclude that ACE2 618-DDC-ABD provides much better survival and organ protection when administered intranasally than when given systemically or after viral inoculation and that lowering brain titers is a critical determinant of survival and organ protection.- Published
- 2022
- Full Text
- View/download PDF
14. SARS-CoV-2 Diverges from Other Betacoronaviruses in Only Partially Activating the IRE1α/XBP1 Endoplasmic Reticulum Stress Pathway in Human Lung-Derived Cells.
- Author
-
Nguyen LC, Renner DM, Silva D, Yang D, Parenti NA, Medina KM, Nicolaescu V, Gula H, Drayman N, Valdespino A, Mohamed A, Dann C, Wannemo K, Robinson-Mailman L, Gonzalez A, Stock L, Cao M, Qiao Z, Moellering RE, Tay S, Randall G, Beers MF, Rosner MR, Oakes SA, and Weiss SR
- Subjects
- Animals, Mice, Humans, Endoribonucleases genetics, Endoribonucleases metabolism, Endoplasmic Reticulum Stress genetics, SARS-CoV-2 genetics, Inositol, Protein Serine-Threonine Kinases genetics, Ribonucleases genetics, Transcription Factors, RNA, Messenger, Lung metabolism, Interferons, X-Box Binding Protein 1 genetics, COVID-19, Middle East Respiratory Syndrome Coronavirus genetics, Middle East Respiratory Syndrome Coronavirus metabolism
- Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has killed over 6 million individuals worldwide and continues to spread in countries where vaccines are not yet widely available or its citizens are hesitant to become vaccinated. Therefore, it is critical to unravel the molecular mechanisms that allow SARS-CoV-2 and other coronaviruses to infect and overtake the host machinery of human cells. Coronavirus replication triggers endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR), a key host cell pathway widely believed to be essential for viral replication. We examined the master UPR sensor IRE1α kinase/RNase and its downstream transcription factor effector XBP1s, which is processed through an IRE1α-mediated mRNA splicing event, in human lung-derived cells infected with betacoronaviruses. We found that human respiratory coronavirus OC43 (HCoV-OC43), Middle East respiratory syndrome coronavirus (MERS-CoV), and murine coronavirus (MHV) all induce ER stress and strongly trigger the kinase and RNase activities of IRE1α as well as XBP1 splicing. In contrast, SARS-CoV-2 only partially activates IRE1α through autophosphorylation, but its RNase activity fails to splice XBP1. Moreover, while IRE1α was dispensable for replication in human cells for all coronaviruses tested, it was required for maximal expression of genes associated with several key cellular functions, including the interferon signaling pathway, during SARS-CoV-2 infection. Our data suggest that SARS-CoV-2 actively inhibits the RNase of autophosphorylated IRE1α, perhaps as a strategy to eliminate detection by the host immune system. IMPORTANCE SARS-CoV-2 is the third lethal respiratory coronavirus, after MERS-CoV and SARS-CoV, to emerge this century, causing millions of deaths worldwide. Other common coronaviruses such as HCoV-OC43 cause less severe respiratory disease. Thus, it is imperative to understand the similarities and differences among these viruses in how each interacts with host cells. We focused here on the inositol-requiring enzyme 1α (IRE1α) pathway, part of the host unfolded protein response to virus-induced stress. We found that while MERS-CoV and HCoV-OC43 fully activate the IRE1α kinase and RNase activities, SARS-CoV-2 only partially activates IRE1α, promoting its kinase activity but not RNase activity. Based on IRE1α-dependent gene expression changes during infection, we propose that SARS-CoV-2 prevents IRE1α RNase activation as a strategy to limit detection by the host immune system.
- Published
- 2022
- Full Text
- View/download PDF
15. SARS-CoV-2 diverges from other betacoronaviruses in only partially activating the IRE1α/XBP1 ER stress pathway in human lung-derived cells.
- Author
-
Nguyen LC, Renner DM, Silva D, Yang D, Parenti N, Medina KM, Nicolaescu V, Gula H, Drayman N, Valdespino A, Mohamed A, Dann C, Wannemo K, Robinson-Mailman L, Gonzalez A, Stock L, Cao M, Qiao Z, Moellering RE, Tay S, Randall G, Beers MF, Rosner MR, Oakes SA, and Weiss SR
- Abstract
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has killed over 6 million individuals worldwide and continues to spread in countries where vaccines are not yet widely available, or its citizens are hesitant to become vaccinated. Therefore, it is critical to unravel the molecular mechanisms that allow SARS-CoV-2 and other coronaviruses to infect and overtake the host machinery of human cells. Coronavirus replication triggers endoplasmic reticulum (ER) stress and activation of the unfolded protein response (UPR), a key host cell pathway widely believed essential for viral replication. We examined the master UPR sensor IRE1α kinase/RNase and its downstream transcription factor effector XBP1s, which is processed through an IRE1α-mediated mRNA splicing event, in human lung-derived cells infected with betacoronaviruses. We found human respiratory coronavirus OC43 (HCoV-OC43), Middle East respiratory syndrome coronavirus (MERS-CoV), and murine coronavirus (MHV) all induce ER stress and strongly trigger the kinase and RNase activities of IRE1α as well as XBP1 splicing. In contrast, SARS-CoV-2 only partially activates IRE1α through autophosphorylation, but its RNase activity fails to splice XBP1. Moreover, while IRE1α was dispensable for replication in human cells for all coronaviruses tested, it was required for maximal expression of genes associated with several key cellular functions, including the interferon signaling pathway, during SARS-CoV-2 infection. Our data suggest that SARS-CoV-2 actively inhibits the RNase of autophosphorylated IRE1α, perhaps as a strategy to eliminate detection by the host immune system., Importance: SARS-CoV-2 is the third lethal respiratory coronavirus after MERS-CoV and SARS-CoV to emerge this century, causing millions of deaths world-wide. Other common coronaviruses such as HCoV-OC43 cause less severe respiratory disease. Thus, it is imperative to understand the similarities and differences among these viruses in how each interacts with host cells. We focused here on the inositol-requiring enzyme 1α (IRE1α) pathway, part of the host unfolded protein response to virus-induced stress. We found that while MERS-CoV and HCoV-OC43 fully activate the IRE1α kinase and RNase activities, SARS-CoV-2 only partially activates IRE1α, promoting its kinase activity but not RNase activity. Based on IRE1α-dependent gene expression changes during infection, we propose that SARS-CoV-2 prevents IRE1α RNase activation as a strategy to limit detection by the host immune system.
- Published
- 2022
- Full Text
- View/download PDF
16. A comprehensive SARS-CoV-2-human protein-protein interactome network identifies pathobiology and host-targeting therapies for COVID-19.
- Author
-
Zhou Y, Liu Y, Gupta S, Paramo MI, Hou Y, Mao C, Luo Y, Judd J, Wierbowski S, Bertolotti M, Nerkar M, Jehi L, Drayman N, Nicolaescu V, Gula H, Tay S, Randall G, Lis JT, Feschotte C, Erzurum SC, Cheng F, and Yu H
- Abstract
Physical interactions between viral and host proteins are responsible for almost all aspects of the viral life cycle and the host's immune response. Studying viral-host protein-protein interactions is thus crucial for identifying strategies for treatment and prevention of viral infection. Here, we use high-throughput yeast two-hybrid and affinity purification followed by mass spectrometry to generate a comprehensive SARS-CoV-2-human protein-protein interactome network consisting of both binary and co-complex interactions. We report a total of 739 high-confidence interactions, showing the highest overlap of interaction partners among published datasets as well as the highest overlap with genes differentially expressed in samples (such as upper airway and bronchial epithelial cells) from patients with SARS-CoV-2 infection. Showcasing the utility of our network, we describe a novel interaction between the viral accessory protein ORF3a and the host zinc finger transcription factor ZNF579 to illustrate a SARS-CoV-2 factor mediating a direct impact on host transcription. Leveraging our interactome, we performed network-based drug screens for over 2,900 FDA-approved/investigational drugs and obtained a curated list of 23 drugs that had significant network proximities to SARS-CoV-2 host factors, one of which, carvedilol, showed promising antiviral properties. We performed electronic health record-based validation using two independent large-scale, longitudinal COVID-19 patient databases and found that carvedilol usage was associated with a significantly lowered probability (17%-20%, P < 0.001) of obtaining a SARS-CoV-2 positive test after adjusting various confounding factors. Carvedilol additionally showed anti-viral activity against SARS-CoV-2 in a human lung epithelial cell line [half maximal effective concentration (EC
50 ) value of 4.1 µM], suggesting a mechanism for its beneficial effect in COVID-19. Our study demonstrates the value of large-scale network systems biology approaches for extracting biological insight from complex biological processes.- Published
- 2022
- Full Text
- View/download PDF
17. The cargo adapter protein CLINT1 is phosphorylated by the Numb-associated kinase BIKE and mediates dengue virus infection.
- Author
-
Schor S, Pu S, Nicolaescu V, Azari S, Kõivomägi M, Karim M, Cassonnet P, Saul S, Neveu G, Yueh A, Demeret C, Skotheim JM, Jacob Y, Randall G, and Einav S
- Subjects
- Animals, Humans, Phosphorylation, Two-Hybrid System Techniques, Virus Replication, Dengue metabolism, Dengue Virus metabolism
- Abstract
The signaling pathways and cellular functions regulated by the four Numb-associated kinases are largely unknown. We reported that AAK1 and GAK control intracellular trafficking of RNA viruses and revealed a requirement for BIKE in early and late stages of dengue virus (DENV) infection. However, the downstream targets phosphorylated by BIKE have not yet been identified. Here, to identify BIKE substrates, we conducted a barcode fusion genetics-yeast two-hybrid screen and retrieved publicly available data generated via affinity-purification mass spectrometry. We subsequently validated 19 of 47 putative BIKE interactors using mammalian cell-based protein-protein interaction assays. We found that CLINT1, a cargo-specific adapter implicated in bidirectional Golgi-to-endosome trafficking, emerged as a predominant hit in both screens. Our experiments indicated that BIKE catalyzes phosphorylation of a threonine 294 CLINT1 residue both in vitro and in cell culture. Our findings revealed that CLINT1 phosphorylation mediates its binding to the DENV nonstructural 3 protein and subsequently promotes DENV assembly and egress. Additionally, using live-cell imaging we revealed that CLINT1 cotraffics with DENV particles and is involved in mediating BIKE's role in DENV infection. Finally, our data suggest that additional cellular BIKE interactors implicated in the host immune and stress responses and the ubiquitin proteasome system might also be candidate phosphorylation substrates of BIKE. In conclusion, these findings reveal cellular substrates and pathways regulated by the understudied Numb-associated kinase enzyme BIKE, a mechanism for CLINT1 regulation, and control of DENV infection via BIKE signaling, with potential implications for cell biology, virology, and host-targeted antiviral design., Competing Interests: Conflict of interest The authors declare that they have no conflicts of interest with the contents of this article., (Copyright © 2022 The Authors. Published by Elsevier Inc. All rights reserved.)
- Published
- 2022
- Full Text
- View/download PDF
18. Differential effects of macrophage subtypes on SARS-CoV-2 infection in a human pluripotent stem cell-derived model.
- Author
-
Lian Q, Zhang K, Zhang Z, Duan F, Guo L, Luo W, Mok BW, Thakur A, Ke X, Motallebnejad P, Nicolaescu V, Chen J, Ma CY, Zhou X, Han S, Han T, Zhang W, Tan AY, Zhang T, Wang X, Xu D, Xiang J, Xu A, Liao C, Huang FP, Chen YW, Na J, Randall G, Tse HF, Chen Z, Chen Y, and Chen HJ
- Subjects
- Humans, Lung, Macrophages, SARS-CoV-2, COVID-19, Pluripotent Stem Cells
- Abstract
Dysfunctional immune responses contribute critically to the progression of Coronavirus Disease-2019 (COVID-19), with macrophages as one of the main cell types involved. It is urgent to understand the interactions among permissive cells, macrophages, and the SARS-CoV-2 virus, thereby offering important insights into effective therapeutic strategies. Here, we establish a lung and macrophage co-culture system derived from human pluripotent stem cells (hPSCs), modeling the host-pathogen interaction in SARS-CoV-2 infection. We find that both classically polarized macrophages (M1) and alternatively polarized macrophages (M2) have inhibitory effects on SARS-CoV-2 infection. However, M1 and non-activated (M0) macrophages, but not M2 macrophages, significantly up-regulate inflammatory factors upon viral infection. Moreover, M1 macrophages suppress the growth and enhance apoptosis of lung cells. Inhibition of viral entry using an ACE2 blocking antibody substantially enhances the activity of M2 macrophages. Our studies indicate differential immune response patterns in distinct macrophage phenotypes, which could lead to a range of COVID-19 disease severity., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
19. Spherical nucleic acids as an infectious disease vaccine platform.
- Author
-
Teplensky MH, Distler ME, Kusmierz CD, Evangelopoulos M, Gula H, Elli D, Tomatsidou A, Nicolaescu V, Gelarden I, Yeldandi A, Batlle D, Missiakas D, and Mirkin CA
- Subjects
- Animals, Biotechnology, COVID-19 prevention & control, Communicable Diseases etiology, Communicable Diseases immunology, Humans, Nucleic Acids chemistry, SARS-CoV-2 immunology, Vaccine Development, Vaccines, DNA genetics, Viral Vaccines genetics, Viral Vaccines immunology, Communicable Disease Control methods, Nucleic Acids immunology, Vaccines, DNA immunology
- Abstract
SignificanceUsing SARS-CoV-2 as a relevant case study for infectious disease, we investigate the structure-function relationships that dictate antiviral spherical nucleic acid (SNA) vaccine efficacy. We show that the SNA architecture can be rapidly employed to target COVID-19 through incorporation of the receptor-binding domain, and that the resulting vaccine potently activates human cells in vitro and mice in vivo. Furthermore, when challenged with a lethal viral infection, only mice treated with the SNA vaccine survived. Taken together, this work underscores the importance of rational vaccine design for infectious disease to yield vaccines that elicit more potent immune responses to effectively fight disease.
- Published
- 2022
- Full Text
- View/download PDF
20. Cannabidiol inhibits SARS-CoV-2 replication through induction of the host ER stress and innate immune responses.
- Author
-
Nguyen LC, Yang D, Nicolaescu V, Best TJ, Gula H, Saxena D, Gabbard JD, Chen SN, Ohtsuki T, Friesen JB, Drayman N, Mohamed A, Dann C, Silva D, Robinson-Mailman L, Valdespino A, Stock L, Suárez E, Jones KA, Azizi SA, Demarco JK, Severson WE, Anderson CD, Millis JM, Dickinson BC, Tay S, Oakes SA, Pauli GF, Palmer KE, Meltzer DO, Randall G, and Rosner MR
- Subjects
- A549 Cells, Animals, Antiviral Agents chemistry, COVID-19 virology, Cannabidiol chemistry, Cannabidiol metabolism, Chlorocebus aethiops, Endoplasmic Reticulum Stress drug effects, Endoribonucleases genetics, Endoribonucleases metabolism, Epithelial Cells virology, Female, Gene Expression Regulation, Viral drug effects, Host-Pathogen Interactions physiology, Humans, Interferons metabolism, Mice, Protein Serine-Threonine Kinases genetics, Protein Serine-Threonine Kinases metabolism, SARS-CoV-2 physiology, Vero Cells, Virus Internalization drug effects, Virus Replication drug effects, COVID-19 Drug Treatment, Antiviral Agents pharmacology, Cannabidiol pharmacology, Host-Pathogen Interactions drug effects, Immunity, Innate drug effects, SARS-CoV-2 drug effects
- Abstract
The spread of SARS-CoV-2 and ongoing COVID-19 pandemic underscores the need for new treatments. Here we report that cannabidiol (CBD) inhibits infection of SARS-CoV-2 in cells and mice. CBD and its metabolite 7-OH-CBD, but not THC or other congeneric cannabinoids tested, potently block SARS-CoV-2 replication in lung epithelial cells. CBD acts after viral entry, inhibiting viral gene expression and reversing many effects of SARS-CoV-2 on host gene transcription. CBD inhibits SARS-CoV-2 replication in part by up-regulating the host IRE1α RNase endoplasmic reticulum (ER) stress response and interferon signaling pathways. In matched groups of human patients from the National COVID Cohort Collaborative, CBD (100 mg/ml oral solution per medical records) had a significant negative association with positive SARS-CoV-2 tests. This study highlights CBD as a potential preventative agent for early-stage SARS-CoV-2 infection and merits future clinical trials. We caution against use of non-medical formulations including edibles, inhalants or topicals as a preventative or treatment therapy at the present time.
- Published
- 2022
- Full Text
- View/download PDF
21. Circulating ACE2-expressing extracellular vesicles block broad strains of SARS-CoV-2.
- Author
-
El-Shennawy L, Hoffmann AD, Dashzeveg NK, McAndrews KM, Mehl PJ, Cornish D, Yu Z, Tokars VL, Nicolaescu V, Tomatsidou A, Mao C, Felicelli CJ, Tsai CF, Ostiguin C, Jia Y, Li L, Furlong K, Wysocki J, Luo X, Ruivo CF, Batlle D, Hope TJ, Shen Y, Chae YK, Zhang H, LeBleu VS, Shi T, Swaminathan S, Luo Y, Missiakas D, Randall GC, Demonbreun AR, Ison MG, Kalluri R, Fang D, and Liu H
- Subjects
- 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, Angiotensin-Converting Enzyme 2 immunology, COVID-19 immunology, Extracellular Vesicles immunology, SARS-CoV-2 immunology
- 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, β, 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., (© 2022. The Author(s).)
- Published
- 2022
- Full Text
- View/download PDF
22. Generation of potent cellular and humoral immunity against SARS-CoV-2 antigens via conjugation to a polymeric glyco-adjuvant.
- Author
-
Gray LT, Raczy MM, Briquez PS, Marchell TM, Alpar AT, Wallace RP, Volpatti LR, Sasso MS, Cao S, Nguyen M, Mansurov A, Budina E, Watkins EA, Solanki A, Mitrousis N, Reda JW, Yu SS, Tremain AC, Wang R, Nicolaescu V, Furlong K, Dvorkin S, Manicassamy B, Randall G, Wilson DS, Kwissa M, Swartz MA, and Hubbell JA
- Subjects
- Adjuvants, Immunologic, Aged, Animals, Antibodies, Neutralizing, Antibodies, Viral, CD8-Positive T-Lymphocytes, COVID-19 Vaccines, Humans, Immunity, Cellular, Mice, SARS-CoV-2, COVID-19, Immunity, Humoral
- Abstract
The SARS-CoV-2 virus has caused an unprecedented global crisis, and curtailing its spread requires an effective vaccine which elicits a diverse and robust immune response. We have previously shown that vaccines made of a polymeric glyco-adjuvant conjugated to an antigen were effective in triggering such a response in other disease models and hypothesized that the technology could be adapted to create an effective vaccine against SARS-CoV-2. The core of the vaccine platform is the copolymer p(Man-TLR7), composed of monomers with pendant mannose or a toll-like receptor 7 (TLR7) agonist. Thus, p(Man-TLR7) is designed to target relevant antigen-presenting cells (APCs) via mannose-binding receptors and then activate TLR7 upon endocytosis. The p(Man-TLR7) construct is amenable to conjugation to protein antigens such as the Spike protein of SARS-CoV-2, yielding Spike-p(Man-TLR7). Here, we demonstrate Spike-p(Man-TLR7) vaccination elicits robust antigen-specific cellular and humoral responses in mice. In adult and elderly wild-type mice, vaccination with Spike-p(Man-TLR7) generates high and long-lasting titers of anti-Spike IgGs, with neutralizing titers exceeding levels in convalescent human serum. Interestingly, adsorbing Spike-p(Man-TLR7) to the depot-forming adjuvant alum amplified the broadly neutralizing humoral responses to levels matching those in mice vaccinated with formulations based off of clinically-approved adjuvants. Additionally, we observed an increase in germinal center B cells, antigen-specific antibody secreting cells, activated T follicular helper cells, and polyfunctional Th1-cytokine producing CD4
+ and CD8+ T cells. We conclude that Spike-p(Man-TLR7) is an attractive, next-generation subunit vaccine candidate, capable of inducing durable and robust antibody and T cell responses., (Copyright © 2021 The Authors. Published by Elsevier Ltd.. All rights reserved.)- Published
- 2021
- Full Text
- View/download PDF
23. Polymersomes Decorated with the SARS-CoV-2 Spike Protein Receptor-Binding Domain Elicit Robust Humoral and Cellular Immunity.
- Author
-
Volpatti LR, Wallace RP, Cao S, Raczy MM, Wang R, Gray LT, Alpar AT, Briquez PS, Mitrousis N, Marchell TM, Sasso MS, Nguyen M, Mansurov A, Budina E, Solanki A, Watkins EA, Schnorenberg MR, Tremain AC, Reda JW, Nicolaescu V, Furlong K, Dvorkin S, Yu SS, Manicassamy B, LaBelle JL, Tirrell MV, Randall G, Kwissa M, Swartz MA, and Hubbell JA
- Abstract
The COVID-19 pandemic underscores the need for rapid, safe, and effective vaccines. In contrast to some traditional vaccines, nanoparticle-based subunit vaccines are particularly efficient in trafficking antigens to lymph nodes, where they induce potent immune cell activation. Here, we developed a strategy to decorate the surface of oxidation-sensitive polymersomes with multiple copies of the SARS-CoV-2 spike protein receptor-binding domain (RBD) to mimic the physical form of a virus particle. We evaluated the vaccination efficacy of these surface-decorated polymersomes (RBD
surf ) in mice compared to RBD-encapsulated polymersomes (RBDencap ) and unformulated RBD (RBDfree ), using monophosphoryl-lipid-A-encapsulated polymersomes (MPLA PS) as an adjuvant. While all three groups produced high titers of RBD-specific IgG, only RBDsurf elicited a neutralizing antibody response to SARS-CoV-2 comparable to that of human convalescent plasma. Moreover, RBDsurf was the only group to significantly increase the proportion of RBD-specific germinal center B cells in the vaccination-site draining lymph nodes. Both RBDsurf and RBDencap drove similarly robust CD4+ and CD8+ T cell responses that produced multiple Th1-type cytokines. We conclude that a multivalent surface display of spike RBD on polymersomes promotes a potent neutralizing antibody response to SARS-CoV-2, while both antigen formulations promote robust T cell immunity., Competing Interests: The authors declare the following competing financial interest(s): M.A.S. and J.A.H. have patents related to the polymersome technology and interests in LantaBio, which has licensed those patents., (© 2021 The Authors. Published by American Chemical Society.)- Published
- 2021
- Full Text
- View/download PDF
24. Masitinib is a broad coronavirus 3CL inhibitor that blocks replication of SARS-CoV-2.
- Author
-
Drayman N, DeMarco JK, Jones KA, Azizi SA, Froggatt HM, Tan K, Maltseva NI, Chen S, Nicolaescu V, Dvorkin S, Furlong K, Kathayat RS, Firpo MR, Mastrodomenico V, Bruce EA, Schmidt MM, Jedrzejczak R, Muñoz-Alía MÁ, Schuster B, Nair V, Han KY, O'Brien A, Tomatsidou A, Meyer B, Vignuzzi M, Missiakas D, Botten JW, Brooke CB, Lee H, Baker SC, Mounce BC, Heaton NS, Severson WE, Palmer KE, Dickinson BC, Joachimiak A, Randall G, and Tay S
- Subjects
- A549 Cells, Animals, Antiviral Agents chemistry, Antiviral Agents metabolism, Antiviral Agents therapeutic use, Benzamides, COVID-19 virology, Catalytic Domain, Coronavirus 3C Proteases chemistry, Coronavirus 3C Proteases metabolism, Coronavirus OC43, Human physiology, Cysteine Proteinase Inhibitors chemistry, Cysteine Proteinase Inhibitors metabolism, HEK293 Cells, Humans, Inhibitory Concentration 50, Mice, Mice, Transgenic, Microbial Sensitivity Tests, Piperidines, Pyridines, SARS-CoV-2 enzymology, SARS-CoV-2 physiology, Thiazoles chemistry, Thiazoles metabolism, Thiazoles therapeutic use, Viral Load drug effects, Virus Replication drug effects, Antiviral Agents pharmacology, Coronavirus 3C Proteases antagonists & inhibitors, Coronavirus OC43, Human drug effects, Cysteine Proteinase Inhibitors pharmacology, SARS-CoV-2 drug effects, Thiazoles pharmacology, COVID-19 Drug Treatment
- Abstract
There is an urgent need for antiviral agents that treat severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. We screened a library of 1900 clinically safe drugs against OC43, a human beta coronavirus that causes the common cold, and evaluated the top hits against SARS-CoV-2. Twenty drugs significantly inhibited replication of both viruses in cultured human cells. Eight of these drugs inhibited the activity of the SARS-CoV-2 main protease, 3CLpro, with the most potent being masitinib, an orally bioavailable tyrosine kinase inhibitor. X-ray crystallography and biochemistry show that masitinib acts as a competitive inhibitor of 3CLpro. Mice infected with SARS-CoV-2 and then treated with masitinib showed >200-fold reduction in viral titers in the lungs and nose, as well as reduced lung inflammation. Masitinib was also effective in vitro against all tested variants of concern (B.1.1.7, B.1.351, and P.1)., (Copyright © 2021 The Authors, some rights reserved; exclusive licensee American Association for the Advancement of Science. No claim to original U.S. Government Works.)
- Published
- 2021
- Full Text
- View/download PDF
25. Polymersomes decorated with SARS-CoV-2 spike protein receptor binding domain elicit robust humoral and cellular immunity.
- Author
-
Volpatti LR, Wallace RP, Cao S, Raczy MM, Wang R, Gray LT, Alpar AT, Briquez PS, Mitrousis N, Marchell TM, Sasso MS, Nguyen M, Mansurov A, Budina E, Solanki A, Watkins EA, Schnorenberg MR, Tremain AC, Reda JW, Nicolaescu V, Furlong K, Dvorkin S, Yu SS, Manicassamy B, LaBelle JL, Tirrell MV, Randall G, Kwissa M, Swartz MA, and Hubbell JA
- Abstract
A diverse portfolio of SARS-CoV-2 vaccine candidates is needed to combat the evolving COVID-19 pandemic. Here, we developed a subunit nanovaccine by conjugating SARS-CoV-2 Spike protein receptor binding domain (RBD) to the surface of oxidation-sensitive polymersomes. We evaluated the humoral and cellular responses of mice immunized with these surface-decorated polymersomes (RBD
surf ) compared to RBD-encapsulated polymersomes (RBDencap ) and unformulated RBD (RBDfree ), using monophosphoryl lipid A-encapsulated polymersomes (MPLA PS) as an adjuvant. While all three groups produced high titers of RBD-specific IgG, only RBDsurf elicited a neutralizing antibody response to SARS-CoV-2 comparable to that of human convalescent plasma. Moreover, RBDsurf was the only group to significantly increase the proportion of RBD-specific germinal center B cells in the vaccination-site draining lymph nodes. Both RBDsurf and RBDencap drove similarly robust CD4+ and CD8+ T cell responses that produced multiple Th1-type cytokines. We conclude that multivalent surface display of Spike RBD on polymersomes promotes a potent neutralizing antibody response to SARS-CoV-2, while both antigen formulations promote robust T cell immunity., Competing Interests: COMPETING INTERESTS M.A.S. and J.A.H. have patents related to the polymersome technology and interests in LantaBio, which has licensed those patents.- Published
- 2021
- Full Text
- View/download PDF
26. Cannabidiol Inhibits SARS-CoV-2 Replication and Promotes the Host Innate Immune Response.
- Author
-
Nguyen LC, Yang D, Nicolaescu V, Best TJ, Ohtsuki T, Chen SN, Friesen JB, Drayman N, Mohamed A, Dann C, Silva D, Gula H, Jones KA, Millis JM, Dickinson BC, Tay S, Oakes SA, Pauli GF, Meltzer DO, Randall G, and Rosner MR
- Abstract
The rapid spread of COVID-19 underscores the need for new treatments. Here we report that cannabidiol (CBD), a compound produced by the cannabis plant, inhibits SARS-CoV-2 infection. CBD and its metabolite, 7-OH-CBD, but not congeneric cannabinoids, potently block SARS-CoV-2 replication in lung epithelial cells. CBD acts after cellular infection, inhibiting viral gene expression and reversing many effects of SARS-CoV-2 on host gene transcription. CBD induces interferon expression and up-regulates its antiviral signaling pathway. A cohort of human patients previously taking CBD had significantly lower SARS-CoV-2 infection incidence of up to an order of magnitude relative to matched pairs or the general population. This study highlights CBD, and its active metabolite, 7-OH-CBD, as potential preventative agents and therapeutic treatments for SARS-CoV-2 at early stages of infection.
- Published
- 2021
- Full Text
- View/download PDF
27. Tipiracil binds to uridine site and inhibits Nsp15 endoribonuclease NendoU from SARS-CoV-2.
- Author
-
Kim Y, Wower J, Maltseva N, Chang C, Jedrzejczak R, Wilamowski M, Kang S, Nicolaescu V, Randall G, Michalska K, and Joachimiak A
- Subjects
- A549 Cells, Antiviral Agents chemistry, Antiviral Agents pharmacokinetics, Catalytic Domain, Crystallography, X-Ray, Endoribonucleases chemistry, Endoribonucleases metabolism, Enzyme Inhibitors chemistry, Enzyme Inhibitors pharmacokinetics, Humans, Ligands, Models, Molecular, Protein Conformation, Pyrrolidines chemistry, Pyrrolidines pharmacokinetics, Thymine chemistry, Thymine pharmacokinetics, Uridine metabolism, Viral Nonstructural Proteins chemistry, Viral Nonstructural Proteins metabolism, Antiviral Agents pharmacology, COVID-19 virology, Endoribonucleases antagonists & inhibitors, Enzyme Inhibitors pharmacology, Pyrrolidines pharmacology, SARS-CoV-2 drug effects, SARS-CoV-2 enzymology, Thymine pharmacology, Viral Nonstructural Proteins antagonists & inhibitors, COVID-19 Drug Treatment
- Abstract
SARS-CoV-2 Nsp15 is a uridine-specific endoribonuclease with C-terminal catalytic domain belonging to the EndoU family that is highly conserved in coronaviruses. As endoribonuclease activity seems to be responsible for the interference with the innate immune response, Nsp15 emerges as an attractive target for therapeutic intervention. Here we report the first structures with bound nucleotides and show how the enzyme specifically recognizes uridine moiety. In addition to a uridine site we present evidence for a second base binding site that can accommodate any base. The structure with a transition state analog, uridine vanadate, confirms interactions key to catalytic mechanisms. In the presence of manganese ions, the enzyme cleaves unpaired RNAs. This acquired knowledge was instrumental in identifying Tipiracil, an FDA approved drug that is used in the treatment of colorectal cancer, as a potential anti-COVID-19 drug. Using crystallography, biochemical, and whole-cell assays, we demonstrate that Tipiracil inhibits SARS-CoV-2 Nsp15 by interacting with the uridine binding pocket in the enzyme's active site. Our findings provide new insights for the development of uracil scaffold-based drugs.
- Published
- 2021
- Full Text
- View/download PDF
28. Structure of papain-like protease from SARS-CoV-2 and its complexes with non-covalent inhibitors.
- Author
-
Osipiuk J, Azizi SA, Dvorkin S, Endres M, Jedrzejczak R, Jones KA, Kang S, Kathayat RS, Kim Y, Lisnyak VG, Maki SL, Nicolaescu V, Taylor CA, Tesar C, Zhang YA, Zhou Z, Randall G, Michalska K, Snyder SA, Dickinson BC, and Joachimiak A
- Subjects
- Antiviral Agents pharmacology, Humans, Mutation, Polyproteins metabolism, Substrate Specificity, Virus Replication drug effects, Papain metabolism, Peptide Hydrolases metabolism, SARS-CoV-2 drug effects, SARS-CoV-2 enzymology
- Abstract
The pandemic caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) continues to expand. Papain-like protease (PLpro) is one of two SARS-CoV-2 proteases potentially targetable with antivirals. PLpro is an attractive target because it plays an essential role in cleavage and maturation of viral polyproteins, assembly of the replicase-transcriptase complex, and disruption of host responses. We report a substantive body of structural, biochemical, and virus replication studies that identify several inhibitors of the SARS-CoV-2 enzyme. We determined the high resolution structure of wild-type PLpro, the active site C111S mutant, and their complexes with inhibitors. This collection of structures details inhibitors recognition and interactions providing fundamental molecular and mechanistic insight into PLpro. All compounds inhibit the peptidase activity of PLpro in vitro, some block SARS-CoV-2 replication in cell culture assays. These findings will accelerate structure-based drug design efforts targeting PLpro to identify high-affinity inhibitors of clinical value.
- Published
- 2021
- Full Text
- View/download PDF
29. Drug repurposing screen identifies masitinib as a 3CLpro inhibitor that blocks replication of SARS-CoV-2 in vitro .
- Author
-
Drayman N, Jones KA, Azizi SA, Froggatt HM, Tan K, Maltseva NI, Chen S, Nicolaescu V, Dvorkin S, Furlong K, Kathayat RS, Firpo MR, Mastrodomenico V, Bruce EA, Schmidt MM, Jedrzejczak R, Muñoz-Alía MÁ, Schuster B, Nair V, Botten JW, Brooke CB, Baker SC, Mounce BC, Heaton NS, Dickinson BC, Jaochimiak A, Randall G, and Tay S
- Abstract
There is an urgent need for anti-viral agents that treat SARS-CoV-2 infection. The shortest path to clinical use is repurposing of drugs that have an established safety profile in humans. Here, we first screened a library of 1,900 clinically safe drugs for inhibiting replication of OC43, a human beta-coronavirus that causes the common-cold and is a relative of SARS-CoV-2, and identified 108 effective drugs. We further evaluated the top 26 hits and determined their ability to inhibit SARS-CoV-2, as well as other pathogenic RNA viruses. 20 of the 26 drugs significantly inhibited SARS-CoV-2 replication in human lung cells (A549 epithelial cell line), with EC50 values ranging from 0.1 to 8 micromolar. We investigated the mechanism of action for these and found that masitinib, a drug originally developed as a tyrosine-kinase inhibitor for cancer treatment, strongly inhibited the activity of the SARS-CoV-2 main protease 3CLpro. X-ray crystallography revealed that masitinib directly binds to the active site of 3CLpro, thereby blocking its enzymatic activity. Mastinib also inhibited the related viral protease of picornaviruses and blocked picornaviruses replication. Thus, our results show that masitinib has broad anti-viral activity against two distinct beta-coronaviruses and multiple picornaviruses that cause human disease and is a strong candidate for clinical trials to treat SARS-CoV-2 infection.
- Published
- 2020
- Full Text
- View/download PDF
30. Interactions between the Hepatitis C Virus Nonstructural 2 Protein and Host Adaptor Proteins 1 and 4 Orchestrate Virus Release.
- Author
-
Xiao F, Wang S, Barouch-Bentov R, Neveu G, Pu S, Beer M, Schor S, Kumar S, Nicolaescu V, Lindenbach BD, Randall G, and Einav S
- Subjects
- Cell Line, Humans, Immunoprecipitation, Protein Binding, Protein Interaction Mapping, Adaptor Protein Complex 1 metabolism, Adaptor Protein Complex 4 metabolism, Hepacivirus physiology, Host-Pathogen Interactions, Viral Nonstructural Proteins metabolism, Virus Release
- Abstract
Hepatitis C virus (HCV) spreads via secreted cell-free particles or direct cell-to-cell transmission. Yet, virus-host determinants governing differential intracellular trafficking of cell-free- and cell-to-cell-transmitted virus remain unknown. The host adaptor proteins (APs) AP-1A, AP-1B, and AP-4 traffic in post-Golgi compartments, and the latter two are implicated in basolateral sorting. We reported that AP-1A mediates HCV trafficking during release, whereas the endocytic adaptor AP-2 mediates entry and assembly. We demonstrated that the host kinases AAK1 and GAK regulate HCV infection by controlling these clathrin-associated APs. Here, we sought to define the roles of AP-4, a clathrin-independent adaptor; AP-1A; and AP-1B in HCV infection. We screened for interactions between HCV proteins and the μ subunits of AP-1A, AP-1B, and AP-4 by mammalian cell-based protein fragment complementation assays. The nonstructural 2 (NS2) protein emerged as an interactor of these adaptors in this screening and by coimmunoprecipitations in HCV-infected cells. Two previously unrecognized dileucine-based motifs in the NS2 C terminus mediated AP binding and HCV release. Infectivity and coculture assays demonstrated that while all three adaptors mediate HCV release and cell-free spread, AP-1B and AP-4, but not AP-1A, mediate cell-to-cell spread. Live-cell imaging revealed HCV cotrafficking with AP-1A, AP-1B, and AP-4 and that AP-4 mediates HCV trafficking in a post-Golgi compartment. Lastly, HCV cell-to-cell spread was regulated by AAK1 and GAK and thus susceptible to treatment with AAK1 and GAK inhibitors. These data provide a mechanistic understanding of HCV trafficking in distinct release pathways and reveal a requirement for APs in cell-to-cell viral spread. IMPORTANCE HCV spreads via cell-free infection or cell-to-cell contact that shields it from antibody neutralization, thereby facilitating viral persistence. Yet, factors governing this differential sorting remain unknown. By integrating proteomic, RNA interference, genetic, live-cell imaging, and pharmacological approaches, we uncover differential coopting of host adaptor proteins (APs) to mediate HCV traffic at distinct late steps of the viral life cycle. We reported that AP-1A and AP-2 mediate HCV trafficking during release and assembly, respectively. Here, we demonstrate that dileucine motifs in the NS2 protein mediate AP-1A, AP-1B, and AP-4 binding and cell-free virus release. Moreover, we reveal that AP-4, an adaptor not previously implicated in viral infections, mediates cell-to-cell spread and HCV trafficking. Lastly, we demonstrate cell-to-cell spread regulation by AAK1 and GAK, host kinases controlling APs, and susceptibility to their inhibitors. This study provides mechanistic insights into virus-host determinants that facilitate HCV trafficking, with potential implications for pathogenesis and antiviral agent design., (Copyright © 2018 Xiao et al.)
- Published
- 2018
- Full Text
- View/download PDF
31. [Coronary risk factors. Anatomoclinical study].
- Author
-
Degeratu T, Nicolaescu V, Nuţă M, Cîmpeanu A, and Cucu N
- Subjects
- Adult, Age Factors, Aged, Arteriosclerosis etiology, Coronary Disease epidemiology, Coronary Disease genetics, Female, Humans, Hypercholesterolemia complications, Male, Middle Aged, Probability, Romania, Sex Factors, Smoking complications, Arteriosclerosis complications, Coronary Disease etiology, Diabetes Complications, Hyperlipidemias complications, Hypertension complications, Obesity complications
- Published
- 1974
32. A comparative study of allogenic "first set" and "second set" skin rejection in mice.
- Author
-
Nedelea M, Dima S, Sandru G, and Nicolaescu V
- Subjects
- Animals, Glycosaminoglycans metabolism, Lymph Nodes pathology, Mice, Skin metabolism, Transplantation, Homologous, Graft Rejection, Skin Transplantation
- Abstract
In our case, where the difference between donor WHT/Ht(H--2d) and recipient C57B1/6 (H--2b) was at the H--2 locus of histocompatibility, the FSg rejection occurred between the 6th and the 10th day, while the SSg rejection was two days earlier. The morphological study emphasized that the cellular infiltrate in the FSg is predominantly lymphocytic, while in the SSg it is predominantly granulocytic. The vascularization settles on the second day postgrafting in the FSg as well as in the SSg, but is scarce and quickly destroyed in the SSg, thus being explained the scanty supply of lymphocytes in the latter graft type. The histochemical reactions demonstrated an increase of the NMPS in skin allograft from the moment of settling till the end of the rejection and a decrease of AMPS, till the complete disappearance, in the rejected graft. Little morphological differences were found between colateral draining nodes and contralateral ones during the reaction to the graft. An important feature described is the presence at the bed graft level of some cells morphologically identical to the IB encountered in great number in the TDA of lymph nodes in the allograft-bearing mice.
- Published
- 1975
33. [Relationship between the level of plasma renin activity and heart function in acute myocardial infarct].
- Author
-
Nicolaescu V, Câmpeanu A, Pleşea O, Rădoi M, Degeratu T, Băjenaru C, Georgescu G, and Zaharescu J
- Subjects
- Adult, Aged, Female, Heart Failure physiopathology, Humans, Male, Middle Aged, Myocardial Infarction diagnosis, Renin-Angiotensin System, Stroke Volume, Heart physiopathology, Myocardial Infarction physiopathology, Renin blood
- Published
- 1984
34. [Evaluation of left ventricular function in hypertensive patients by determination of systolic time (ST)].
- Author
-
Câmpeanu A, Nicolaescu V, Pleşea O, Nuţă M, Rădoi M, Serban-Pârâu G, and Chirilă L
- Subjects
- Adult, Cardiomegaly etiology, Cardiomegaly physiopathology, Electrocardiography, Exercise Test, Female, Humans, Hypertension complications, Male, Middle Aged, Heart Ventricles physiopathology, Hypertension physiopathology, Myocardial Contraction
- Published
- 1978
35. [Clinical study of the anti-arrhythmic effects of oral amiodarone].
- Author
-
Nicolaescu V, Câmpeanu A, and Constantinescu I
- Subjects
- Administration, Oral, Adolescent, Adult, Aged, Child, Female, Humans, Male, Middle Aged, Amiodarone administration & dosage, Arrhythmias, Cardiac drug therapy, Benzofurans administration & dosage
- Published
- 1981
36. [The value of systolic time determinations in the diagnosis of rheumatic carditis].
- Author
-
Nicolaescu V, Guţiu I, Serban-Pârâu G, and Chirilă L
- Subjects
- Adult, Cardiac Output, Female, Heart Function Tests, Humans, Male, Rheumatic Heart Disease physiopathology, Heart physiopathology, Rheumatic Heart Disease diagnosis
- Published
- 1976
37. [Effects of verapamil in arrhythmias].
- Author
-
Câmpeanu A, Nicolaescu V, Pleşa O, Cerin G, Călugăru V, and Carp C
- Subjects
- Adolescent, Adult, Aged, Child, Female, Humans, Male, Middle Aged, Arrhythmias, Cardiac drug therapy, Verapamil therapeutic use
- Published
- 1982
38. On the ecology of arterial hypertension.
- Author
-
Steinbach M, Constantineanu M, Harnagea P, Teodorini S, Georgescu M, Creţescu R, Manicatide M, Nicolaescu V, Suciu A, Vlădescu C, Voiculescu M, and Georgescu A
- Subjects
- Adult, Chlorine analysis, Female, Humans, Hypertension etiology, Hypertension genetics, Male, Middle Aged, Potassium analysis, Romania, Sodium analysis, Water Supply analysis, Disease Reservoirs, Hypertension epidemiology
- Published
- 1974
39. [Arrhythmias and their treatment in chronic cor pulmonale].
- Author
-
Nicolaescu V, Carp C, Câmpeanu A, Nuţă M, and Ciontea M
- Subjects
- Aged, Arrhythmias, Cardiac therapy, Chronic Disease, Digitalis Glycosides administration & dosage, Digitalis Glycosides poisoning, Diuretics administration & dosage, Female, Humans, Male, Middle Aged, Oxygen Inhalation Therapy, Pulmonary Embolism complications, Respiratory Tract Infections complications, Water-Electrolyte Imbalance complications, Arrhythmias, Cardiac etiology, Pulmonary Heart Disease complications
- Published
- 1977
40. [Anticalcium drugs in the treatment of arterial hypertension].
- Author
-
Nicolaescu V and Rădoi M
- Subjects
- Calcium Channel Blockers adverse effects, Chronic Disease, Hemodynamics drug effects, Humans, Hypertension physiopathology, Calcium Channel Blockers therapeutic use, Hypertension drug therapy
- Published
- 1988
41. [Current status of the surgical treatment of valvular diseases].
- Author
-
Rădoi M and Nicolaescu V
- Subjects
- Fascia Lata transplantation, Humans, Postoperative Complications, Transplantation, Autologous, Transplantation, Homologous, Heart Valve Diseases surgery, Heart Valve Prosthesis, Heart Valves transplantation
- Published
- 1974
42. The Wright peak flow meter. Its reliability and practical use.
- Author
-
Manicatide M, Nicolaescu V, Racoveanu C, Teculescu D, Andronache E, Bozianu E, Cucu M, Drăghici A, and Mincu P
- Subjects
- Adolescent, Adult, Air Pollution, Body Height, Child, Female, Humans, Male, Middle Aged, Occupations, School Health Services, Spirometry, Vital Capacity, Pulmonary Ventilation instrumentation
- Published
- 1974
43. [Disseminated subcutaneous bacillary abscesses. Presentation of a case].
- Author
-
Nicolaescu V, Câmpeanu A, and Macarie C
- Subjects
- Aged, Humans, Male, Tuberculosis, Pulmonary complications, Tuberculosis, Cutaneous diagnosis, Tuberculosis, Cutaneous pathology
- Published
- 1974
44. [Value of metoprolol in increasing the tolerance of patients with ischemic heart disease to exertion].
- Author
-
Nicolaescu V, Câmpeanu A, Pleşea O, Serban-Pârâu G, and Chirilă L
- Subjects
- Adult, Humans, Male, Middle Aged, Coronary Disease drug therapy, Metoprolol therapeutic use, Physical Exertion
- Published
- 1986
45. [Antihypertensive effects of labetalol administered parenterally and orally].
- Author
-
Nicolaescu V, Serban-Pârâu G, Ionescu P, and Nuţă M
- Subjects
- Administration, Oral, Blood Pressure drug effects, Chronic Disease, Drug Evaluation, Female, Humans, Hypertension physiopathology, Injections, Intravenous, Male, Middle Aged, Time Factors, Ethanolamines administration & dosage, Hypertension drug therapy, Labetalol administration & dosage
- Published
- 1984
46. Histochemical patterns in human breast tumours.
- Author
-
Duţu R, Nedelea M, Veluda G, and Nicolaescu V
- Subjects
- Breast Neoplasms pathology, Citric Acid Cycle, Female, Glycolysis, Histocytochemistry, Humans, Lipid Metabolism, Nucleoproteins metabolism, Pentoses metabolism, Breast Neoplasms metabolism
- Abstract
Histochemical investigations carried out on 104 breast tumours (10 benign proliferations and 94 carcinomas) showed that breast carcinomas were characterized by various enzymological equipments in relation to tumour differentiation degree, histogenesis, functional stage, site of tumour cells in the carcinomatous islands or cords and to hormonal factors. Tumour cells -- stroma interrelationships study pointed out that high glycolysis (high LDH, NADPH2-TR, NADH2-TR activities) and an intense LEPA-activity of tumour cells seem to be favourable for proliferation and local tumour cells migration.
- Published
- 1979
- Full Text
- View/download PDF
47. [The effects of nitroglycerin administered intravenously in acute myocardial ischemia].
- Author
-
Câmpeanu A, Pleşea O, Serban-Pârâu G, Călugăru V, Bejenariu C, and Nicolaescu V
- Subjects
- Acute Disease, Angina Pectoris drug therapy, Angina Pectoris enzymology, Angina Pectoris physiopathology, Coronary Disease enzymology, Coronary Disease physiopathology, Dipyridamole administration & dosage, Drug Evaluation, Drug Therapy, Combination, Female, Heparin administration & dosage, Humans, Infusions, Intravenous, Male, Middle Aged, Nifedipine administration & dosage, Time Factors, Coronary Disease drug therapy, Nitroglycerin administration & dosage
- Abstract
The effects of i.v. nitroglycerin were studied by ECG and enzymatically in 16 patients (mean age 57.9 +/- 1.4 years) (NTG) in comparison with a control lot (c) of 17 patients (mean age 62.7 +/- 2.1 years) treated with dipyridamole and/or nifedipine (N), admitted in the first 4-10 hours after the onset of the first symptoms. The patients with heart failure and those with Q waves and CPK or LDH values greater than 2 x n were not admitted. NTG was administered in doses of 20 micrograms--60 microgram/hour for 24-96 hours and systolic AT (s) was kept under 10% of the basic values but not under 100 mmHg. Myocardial infarction appeared in 9 N-treated patients (54.86%) and 11 controls (58.25%) (p = 0.07). The size of myocardial necrosis was reduced in the N-treated patients. Peak serum CPK levels had considerably less increases in N (from 72.9 U to 73.4 U) (p greater than 00.5) versus C from 34.2 U to 364.5 U) (p less than 0.001). The sum of segmentary depression failed from 9.13 mm to 3.19 mm (p less than 0.05) in N, whereas in C the decrease was not significant (6.12 mm as against 9.38 mm; p greater than 0.05). The evolution was severe in C, as the angina crises (14 cases versus 2 cases, p less than 0.01) and the extension of the infarction (8 cases versus, 0; p 0.05) less than 0.05) appeared more frequently than in N. Only two patients in C died (p less than 0.05). Therefore, i.v. NTG administration in small doses in acute myocardial infarction leads to immediate disappearance of the anginal pain, lowers the extent of the myocardial necrosis and improves the clinical evolution.
- Published
- 1989
48. Value of exercise test for the detection of bronchial asthma during field surveys in children.
- Author
-
Nicolaescu VV, Bozianu E, Manicatide MA, Ciobanu P, Cucu M, and Racoveanu C
- Subjects
- Bronchial Spasm etiology, Child, Humans, Medical History Taking, Prognosis, Pulmonary Ventilation, Spirometry, Asthma diagnosis, Physical Exertion, Respiratory Function Tests
- Published
- 1974
49. [Action of clonidine on cardiac hemodynamics in hypertensive patients].
- Author
-
Nicolaescu V, Campeanu A, Pleşea O, Rădoi M, Chirilă L, and Carp C
- Subjects
- Adult, Cardiomegaly drug therapy, Clonidine pharmacology, Female, Humans, Male, Middle Aged, Clonidine therapeutic use, Heart drug effects, Hemodynamics drug effects, Hypertension drug therapy
- Published
- 1976
50. [Neuropsychological complications of infectious endocarditis].
- Author
-
Nicolaescu V, Nuţă M, Rădoi M, Hergot L, and Teodorescu V
- Subjects
- Adult, Brain Abscess etiology, Cerebral Hemorrhage etiology, Female, Humans, Intracranial Aneurysm etiology, Intracranial Embolism and Thrombosis etiology, Male, Meningoencephalitis etiology, Middle Aged, Brain Diseases etiology, Endocarditis, Bacterial complications, Mental Disorders etiology
- Published
- 1980
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.