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1.
Sci Rep ; 12(1): 4163, 2022 03 09.
Article in English | MEDLINE | ID: covidwho-1799572

ABSTRACT

SARS-CoV-2 and its variants have persisted in this ongoing COVID-19 pandemic. While the vaccines have greatly reduced the COVID-19 cases, hospitalizations, and death, about half of the world remain unvaccinated due to various reasons. Furthermore, the duration of the immunity gained from COVID-19 vaccination is still unclear. Therefore, there is a need for innovative prophylactic and treatment measures. In response to this need, we previously reported on the successful computer-aided development of potent VHH-based multispecific antibodies that were characterized in vitro. Here, we evaluated in vivo efficacy and safety of the lead trispecific VHH-Fc, ABS-VIR-001. Importantly, our data showed that ABS-VIR-001 treatment prevented SARS-CoV-2 infection and death when provided as an intranasal prophylaxis in a humanized ACE-2 mouse model. In addition, ABS-VIR-001 post-exposure treatment was shown to greatly reduce viral loads by as much as 50-fold. A detailed panel of metabolic and cellular parameters demonstrated that ABS-VIR-001 treatment was overall comparable to the PBS treatment, indicating a favorable safety profile. Notably, our inhibition studies show that ABS-VIR-001 continued to demonstrate unwavering efficacy against SARS-CoV-2 mutants, associated with key variants including Delta and Omicron, owing to its multiple epitope design. Lastly, we rigorously tested and confirmed the excellent thermostability of ABS-VIR-001 when heated to 45 °C for up to 4 weeks. Taken together, our study suggests that ABS-VIR-001 is an efficacious and durable prophylaxis and post-exposure treatment for COVID-19 with promising safety and manufacturability features for global distribution.


Subject(s)
COVID-19/drug therapy , SARS-CoV-2/physiology , Single-Domain Antibodies/therapeutic use , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/metabolism , Animals , Antigen-Antibody Reactions/drug effects , Biomarkers/metabolism , COVID-19/virology , Drug Stability , Humans , Immunocompromised Host , Mice , Mice, Transgenic , SARS-CoV-2/isolation & purification , Single-Domain Antibodies/immunology , Single-Domain Antibodies/pharmacology , Spike Glycoprotein, Coronavirus/immunology , Viral Load
2.
Int J Mol Sci ; 22(20)2021 Oct 09.
Article in English | MEDLINE | ID: covidwho-1736951

ABSTRACT

Throughout history, nature has been acknowledged for being a primordial source of various bioactive molecules in which human macular carotenoids are gaining significant attention. Among 750 natural carotenoids, lutein, zeaxanthin and their oxidative metabolites are selectively accumulated in the macular region of living beings. Due to their vast applications in food, feed, pharmaceutical and nutraceuticals industries, the global market of lutein and zeaxanthin is continuously expanding but chemical synthesis, extraction and purification of these compounds from their natural repertoire e.g., plants, is somewhat costly and technically challenging. In this regard microbial as well as microalgal carotenoids are considered as an attractive alternative to aforementioned challenges. Through the techniques of genetic engineering and gene-editing tools like CRISPR/Cas9, the overproduction of lutein and zeaxanthin in microorganisms can be achieved but the commercial scale applications of such procedures needs to be done. Moreover, these carotenoids are highly unstable and susceptible to thermal and oxidative degradation. Therefore, esterification of these xanthophylls and microencapsulation with appropriate wall materials can increase their shelf-life and enhance their application in food industry. With their potent antioxidant activities, these carotenoids are emerging as molecules of vital importance in chronic degenerative, malignancies and antiviral diseases. Therefore, more research needs to be done to further expand the applications of lutein and zeaxanthin.


Subject(s)
Antioxidants/chemistry , Lutein/chemistry , Zeaxanthins/chemistry , Biological Factors/chemistry , Drug Compounding , Drug Stability , Esterification , Gene Editing , Genetic Engineering , Humans , Macula Lutea/chemistry
3.
Med Sci Monit ; 28: e936523, 2022 Mar 01.
Article in English | MEDLINE | ID: covidwho-1716153

ABSTRACT

The Nuvaxovid™ (NVX-CoV2373) Novavax vaccine is a recombinant spike (S) protein nanoparticle vaccine combined with the Matrix-M adjuvant. On December 20, 2021, the European Commission of the European Union (EU) granted conditional marketing authorization for the Nuvaxovid™ (NVX-CoV2373) Novavax vaccine, following recommendations from the European Medicines Agency (EMA). On February 3, 2022, this vaccine was granted conditional marketing authorization (CMA) in Great Britain by the Medicines and Healthcare Products Regulatory Agency (MHRA) for use in individuals ≥18 years. The two vaccine components elicit both B-lymphocyte and T-lymphocyte immune responses to the S protein of SARS-CoV-2. The full-length S protein in this vaccine has common epitopes that could protect against all the SARS-CoV-2 viral variants. Also, the vaccine is stable and has a shelf life of 9 months when stored at standard refrigerated temperatures of between 2-8°C. This Editorial aims to present an update on the first approval of a protein-based adjuvanted vaccine for SARS-CoV-2, Nuvaxovid (NVX-CoV2373) from Novavax, and why it is such a significant development at this time.


Subject(s)
COVID-19 Vaccines/therapeutic use , COVID-19/prevention & control , Drug Approval , Drug Stability , Drug Storage , European Union , Humans , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , United Kingdom , Vaccination Coverage
4.
J Phys Chem Lett ; 13(5): 1314-1322, 2022 Feb 10.
Article in English | MEDLINE | ID: covidwho-1671478

ABSTRACT

With the global outbreak of SARS-CoV-2, mRNA vaccines became the first type of COVID-19 vaccines to enter clinical trials because of their facile production, low cost, and relative safety, which initiated great advances in mRNA therapeutic techniques. However, the development of mRNA therapeutic techniques still confronts some challenges. First, in vitro transcribed mRNA molecules can be easily degraded by ribonuclease (RNase), resulting in their low stability. Next, the negative charge of mRNA molecules prevents them from direct cell entry. Therefore, finding efficient and safe delivery technology could be the key issue to improve mRNA therapeutic techniques. In this Perspective, we mainly discuss the problems of the existing mRNA-based delivery nanoplatforms, including safety evaluation, administration routes, and preparation technology. Moreover, we also propose some views on strategies to further improve mRNA delivery technology.


Subject(s)
COVID-19 Vaccines/administration & dosage , RNA, Messenger/administration & dosage , Vaccines, Synthetic/administration & dosage , /administration & dosage , Drug Stability , Drug Storage , High-Throughput Screening Assays , Humans
5.
Clin Immunol ; 233: 108888, 2021 12.
Article in English | MEDLINE | ID: covidwho-1517099

ABSTRACT

Human interferon alpha (hIFN-α) administration constitutes the current FDA approved therapy for chronic Hepatitis B and C virus infections. Additionally, hIFN-α treatment efficacy was recently demonstrated in patients with COVID-19. Thus, hIFN-α constitutes a therapeutic alternative for those countries where vaccination is inaccessible and for people who did not respond effectively to vaccination. However, hIFN-α2b exhibits a short plasma half-life resulting in the occurrence of severe side effects. To optimize the cytokine's pharmacokinetic profile, we developed a hyperglycosylated IFN, referred to as GMOP-IFN. Given the significant number of reports showing neutralizing antibodies (NAb) formation after hIFN-α administration, here we applied the DeFT (De-immunization of Functional Therapeutics) approach to develop functional, de-immunized versions of GMOP-IFN. Two GMOP-IFN variants exhibited significantly reduced ex vivo immunogenicity and null antiproliferative activity, while preserving antiviral function. The results obtained in this work indicate that the new de-immunized GMOP-IFN variants constitute promising candidates for antiviral therapy.


Subject(s)
Hepatitis B, Chronic/immunology , Hepatitis C, Chronic/immunology , Interferon-alpha/immunology , Recombinant Proteins/immunology , Adult , Amino Acid Sequence , Animals , Antibodies, Neutralizing/immunology , Antiviral Agents/immunology , Antiviral Agents/pharmacology , CHO Cells , COVID-19/drug therapy , COVID-19/immunology , COVID-19/virology , Cattle , Cell Line , Cell Line, Tumor , Cell Proliferation/drug effects , Cells, Cultured , Cricetinae , Cricetulus , Drug Stability , HEK293 Cells , Hepatitis B, Chronic/drug therapy , Hepatitis B, Chronic/virology , Hepatitis C, Chronic/drug therapy , Hepatitis C, Chronic/virology , Humans , Interferon-alpha/genetics , Interferon-alpha/pharmacology , Recombinant Proteins/pharmacology , SARS-CoV-2/drug effects , SARS-CoV-2/immunology , SARS-CoV-2/physiology
6.
J Biol Chem ; 298(1): 101403, 2022 01.
Article in English | MEDLINE | ID: covidwho-1517316

ABSTRACT

Designed ankyrin repeat proteins (DARPins) are antibody mimetics with high and mostly unexplored potential in drug development. By using in silico analysis and a rationally guided Ala scanning, we identified position 17 of the N-terminal capping repeat to play a key role in overall protein thermostability. The melting temperature of a DARPin domain with a single full-consensus internal repeat was increased by 8 °C to 10 °C when Asp17 was replaced by Leu, Val, Ile, Met, Ala, or Thr. We then transferred the Asp17Leu mutation to various backgrounds, including clinically validated DARPin domains, such as the vascular endothelial growth factor-binding domain of the DARPin abicipar pegol. In all cases, these proteins showed improvements in the thermostability on the order of 8 °C to 16 °C, suggesting the replacement of Asp17 could be generically applicable to this drug class. Molecular dynamics simulations showed that the Asp17Leu mutation reduces electrostatic repulsion and improves van-der-Waals packing, rendering the DARPin domain less flexible and more stable. Interestingly, this beneficial Asp17Leu mutation is present in the N-terminal caps of three of the five DARPin domains of ensovibep, a SARS-CoV-2 entry inhibitor currently in clinical development, indicating this mutation could be partly responsible for the very high melting temperature (>90 °C) of this promising anti-COVID-19 drug. Overall, such N-terminal capping repeats with increased thermostability seem to be beneficial for the development of innovative drugs based on DARPins.


Subject(s)
Antiviral Agents/pharmacology , Temperature , Amino Acid Sequence , Antiviral Agents/chemistry , Antiviral Agents/therapeutic use , COVID-19/drug therapy , COVID-19/virology , Drug Development , Drug Stability , SARS-CoV-2/drug effects , Sequence Alignment
7.
Molecules ; 26(21)2021 Oct 20.
Article in English | MEDLINE | ID: covidwho-1512506

ABSTRACT

Three silver(I) dipeptide complexes [Ag(GlyGly)]n(NO3)n (AgGlyGly), [Ag2(GlyAla)(NO3)2]n (AgGlyAla) and [Ag2(HGlyAsp)(NO3)]n (AgGlyAsp) were prepared, investigated and characterized by vibrational spectroscopy (mid-IR), elemental and thermogravimetric analysis and mass spectrometry. For AgGlyGly, X-ray crystallography was also performed. Their stability in biological testing media was verified by time-dependent NMR measurements. Their in vitro antimicrobial activity was evaluated against selected pathogenic microorganisms. Moreover, the influence of silver(I) dipeptide complexes on microbial film formation was described. Further, the cytotoxicity of the complexes against selected cancer cells (BLM, MDA-MB-231, HeLa, HCT116, MCF-7 and Jurkat) and fibroblasts (BJ-5ta) using a colorimetric MTS assay was tested, and the selectivity index (SI) was identified. The mechanism of action of Ag(I) dipeptide complexes was elucidated and discussed by the study in terms of their binding affinity toward the CT DNA, the ability to cleave the DNA and the ability to influence numbers of cells within each cell cycle phase. The new silver(I) dipeptide complexes are able to bind into DNA by noncovalent interaction, and the topoisomerase I inhibition study showed that the studied complexes inhibit its activity at a concentration of 15 µM.


Subject(s)
Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Antineoplastic Agents/chemistry , Antineoplastic Agents/pharmacology , Coordination Complexes/chemistry , Coordination Complexes/pharmacology , Dipeptides/chemistry , Silver/chemistry , Anti-Infective Agents/chemical synthesis , Antineoplastic Agents/chemical synthesis , Cell Cycle/drug effects , Cell Line, Tumor , Chemical Phenomena , Chemistry Techniques, Synthetic , Coordination Complexes/chemical synthesis , Crystallography, X-Ray , Dose-Response Relationship, Drug , Drug Stability , Humans , Molecular Conformation , Molecular Dynamics Simulation , Spectrum Analysis , Structure-Activity Relationship , Thermogravimetry
8.
ChemMedChem ; 16(23): 3548-3552, 2021 12 06.
Article in English | MEDLINE | ID: covidwho-1400781

ABSTRACT

Over half a century since the description of the first antiviral drug, "old" re-emerging viruses and "new" emerging viruses still represent a serious threat to global health. Their high mutation rate and rapid selection of resistance toward common antiviral drugs, together with the increasing number of co-infections, make the war against viruses quite challenging. Herein we report a host-targeted approach, based on the inhibition of the lipid kinase PI4KIIIß, as a promising strategy for inhibiting the replication of multiple viruses hijacking this protein. We show that bithiazole inhibitors of PI4KIIIß block the replication of human rhinoviruses (hRV), Zika virus (ZIKV) and SARS-CoV-2 at low micromolar and sub-micromolar concentrations. However, while the anti-hRV/ZIKV activity can be directly linked to PI4KIIIß inhibition, the role of PI4KIIIß in SARS-CoV-2 entry/replication is debated.


Subject(s)
1-Phosphatidylinositol 4-Kinase/antagonists & inhibitors , Antiviral Agents/pharmacology , Enzyme Inhibitors/chemistry , Rhinovirus/physiology , SARS-CoV-2/physiology , Thiazoles/chemistry , Virus Replication/drug effects , Zika Virus/physiology , 1-Phosphatidylinositol 4-Kinase/metabolism , Antiviral Agents/chemistry , Antiviral Agents/metabolism , COVID-19/pathology , COVID-19/virology , Cell Line , Drug Stability , Enzyme Inhibitors/metabolism , Enzyme Inhibitors/pharmacology , Humans , SARS-CoV-2/isolation & purification , Thiazoles/metabolism , Zika Virus/isolation & purification , Zika Virus Infection/pathology
9.
Int J Mol Sci ; 21(15)2020 Jul 23.
Article in English | MEDLINE | ID: covidwho-1389381

ABSTRACT

As SARS-CoV-2 is spreading rapidly around the globe, adopting proper actions for confronting and protecting against this virus is an essential and unmet task. Reactive oxygen species (ROS) promoting molecules such as peroxides are detrimental to many viruses, including coronaviruses. In this paper, metal decorated single-wall carbon nanotubes (SWCNTs) were evaluated for hydrogen peroxide (H2O2) adsorption for potential use for designing viral inactivation surfaces. We employed first-principles methods based on the density functional theory (DFT) to investigate the capture of an individual H2O2 molecule on pristine and metal (Pt, Pd, Ni, Cu, Rh, or Ru) decorated SWCNTs. Although the single H2O2 molecule is weakly physisorbed on pristine SWCNT, a significant improvement on its adsorption energy was found by utilizing metal functionalized SWCNT as the adsorbent. It was revealed that Rh-SWCNT and Ru-SWCNT systems demonstrate outstanding performance for H2O2 adsorption. Furthermore, we discovered through calculations that Pt- and Cu-decorated SWNCT-H2O2 systems show high potential for filters for virus removal and inactivation with a very long shelf-life (2.2 × 1012 and 1.9 × 108 years, respectively). The strong adsorption of metal decorated SWCNTs and the long shelf-life of these nanomaterials suggest they are exceptional candidates for designing personal protection equipment against viruses.


Subject(s)
Betacoronavirus/drug effects , Disinfectants/pharmacology , Hydrogen Peroxide/analysis , Nanotubes, Carbon/chemistry , Adsorption , COVID-19 , Coronavirus Infections/prevention & control , Density Functional Theory , Disinfectants/chemistry , Drug Stability , Humans , Iron/chemistry , Iron/pharmacology , Pandemics/prevention & control , Personal Protective Equipment , Platinum/chemistry , Platinum/pharmacology , Pneumonia, Viral/prevention & control , Rhodium/chemistry , Rhodium/pharmacology , Ruthenium/chemistry , Ruthenium/pharmacology , SARS-CoV-2 , Virus Inactivation
10.
Biomed Chromatogr ; 35(12): e5212, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1349236

ABSTRACT

Remdesivir (RDV) is the first antiviral drug, approved by the Food and Drug Administration, to treat severe acute respiratory syndrome coronavirus 2. RDV is a relatively new chemical entity, 'ester prodrug', with no reported stability profile. Due to the urgency of its use and thus fast production, it is important to develop a stability-indicating method for its assay. Chromatographic separation was carried out on a C18 column (250 × 4.6 mm, 5 µm) with dual detection: diode array at 240 nm and fluorescence at λex/em 245/390 nm. Isocratic elution of acetonitrile and distilled water (acidified with phosphoric acid, pH 4) in the ratio of 55:45 (v/v), respectively, was used. The linearity range using HPLC-diode array detection was 0.1-15 µg/mL, whereas that using fluorimetric detection was 0.05-15 µg/mL. As per the International Conference on Harmonization guidelines, RDV has been degraded by accelerated alkaline, acidic, neutral hydrolysis, oxidative, heat, and photolytic stress conditions. Possible degradation hypothesis of the parent molecule has been suggested and illustrated. The proposed methods have achieved selective determination of the intact drug with no peaks overlapping in all assumptions. Extensive degradation confirms threatened drug stability at thermal and basic hydrolytic stressing. The developed methods were fully validated and proved suitable for quality control routine analysis of RDV in raw material and pharmaceutical dosage forms.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/chemistry , COVID-19/drug therapy , Prodrugs/chemistry , Acetonitriles/chemistry , Adenosine Monophosphate/chemistry , Adenosine Monophosphate/pharmacology , Alanine/chemistry , Alanine/pharmacology , Antiviral Agents/pharmacology , Chromatography, High Pressure Liquid/methods , Chromatography, Reverse-Phase/methods , Drug Stability , Hot Temperature , Humans , Hydrolysis , Limit of Detection , Oxidation-Reduction , Photolysis
11.
Molecules ; 26(13)2021 Jun 22.
Article in English | MEDLINE | ID: covidwho-1288957

ABSTRACT

In the current work, a simple, economical, accurate, and precise HPLC method with UV detection was developed to quantify Favipiravir (FVIR) in spiked human plasma using acyclovir (ACVR) as an internal standard in the COVID-19 pandemic time. Both FVIR and ACVR were well separated and resolved on the C18 column using the mobile phase blend of methanol:acetonitrile:20 mM phosphate buffer (pH 3.1) in an isocratic mode flow rate of 1 mL/min with a proportion of 30:10:60 %, v/v/v. The detector wavelength was set at 242 nm. Maximum recovery of FVIR and ACVR from plasma was obtained with dichloromethane (DCM) as extracting solvent. The calibration curve was found to be linear in the range of 3.1-60.0 µg/mL with regression coefficient (r2) = 0.9976. However, with acceptable r2, the calibration data's heteroscedasticity was observed, which was further reduced using weighted linear regression with weighting factor 1/x. Finally, the method was validated concerning sensitivity, accuracy (Inter and Intraday's % RE and RSD were 0.28, 0.65 and 1.00, 0.12 respectively), precision, recovery (89.99%, 89.09%, and 90.81% for LQC, MQC, and HQC, respectively), stability (% RSD for 30-day were 3.04 and 1.71 for LQC and HQC, respectively at -20 °C), and carry-over US-FDA guidance for Bioanalytical Method Validation for researchers in the COVID-19 pandemic crisis. Furthermore, there was no significant difference for selectivity when evaluated at LLOQ concentration of 3 µg/mL of FVIR and relative to the blank.


Subject(s)
Amides/analysis , Amides/blood , Antiviral Agents/analysis , Antiviral Agents/blood , Biological Assay/methods , COVID-19/drug therapy , Chromatography, High Pressure Liquid/methods , Liquid-Liquid Extraction/methods , Pyrazines/analysis , Pyrazines/blood , Acyclovir/analysis , Acyclovir/blood , COVID-19/blood , Calibration , Drug Stability , Freezing , Humans , Reference Standards , Reproducibility of Results , Solvents/chemistry
12.
Sci Rep ; 11(1): 12410, 2021 06 14.
Article in English | MEDLINE | ID: covidwho-1268005

ABSTRACT

In situ generation of antibacterial and antiviral agents by harnessing the catalytic activity of enzymes on surfaces provides an effective eco-friendly approach for disinfection. The perhydrolase (AcT) from Mycobacterium smegmatis catalyzes the perhydrolysis of acetate esters to generate the potent disinfectant, peracetic acid (PAA). In the presence of AcT and its two substrates, propylene glycol diacetate and H2O2, sufficient and continuous PAA is generated over an extended time to kill a wide range of bacteria with the enzyme dissolved in aqueous buffer. For extended self-disinfection, however, active and stable AcT bound onto or incorporated into a surface coating is necessary. In the current study, an active, stable and reusable AcT-based coating was developed by incorporating AcT into a polydopamine (PDA) matrix in a single step, thereby forming a biocatalytic composite onto a variety of surfaces. The resulting AcT-PDA composite coatings on glass, metal and epoxy surfaces yielded up to 7-log reduction of Gram-positive and Gram-negative bacteria when in contact with the biocatalytic coating. This composite coating also possessed potent antiviral activity, and dramatically reduced the infectivity of a SARS-CoV-2 pseudovirus within minutes. The single-step approach enables rapid and facile fabrication of enzyme-based disinfectant composite coatings with high activity and stability, which enables reuse following surface washing. As a result, this enzyme-polymer composite technique may serve as a general strategy for preparing antibacterial and antiviral surfaces for applications in health care and common infrastructure safety, such as in schools, the workplace, transportation, etc.


Subject(s)
Anti-Bacterial Agents/chemistry , Antiviral Agents/chemistry , Bacterial Proteins/chemistry , Hydrolases/chemistry , Indoles/chemistry , Polymers/chemistry , Anti-Bacterial Agents/metabolism , Anti-Bacterial Agents/pharmacology , Antiviral Agents/metabolism , Antiviral Agents/pharmacology , Bacterial Proteins/genetics , Bacterial Proteins/metabolism , COVID-19/pathology , COVID-19/virology , Coated Materials, Biocompatible/chemistry , Coated Materials, Biocompatible/metabolism , Coated Materials, Biocompatible/pharmacology , Drug Stability , Gram-Negative Bacteria/drug effects , Gram-Positive Bacteria/drug effects , Humans , Hydrolases/genetics , Hydrolases/metabolism , Kinetics , Mycobacterium smegmatis/enzymology , Peracetic Acid/metabolism , Recombinant Proteins/biosynthesis , Recombinant Proteins/chemistry , Recombinant Proteins/isolation & purification , SARS-CoV-2/drug effects
13.
J Immunother Cancer ; 9(6)2021 06.
Article in English | MEDLINE | ID: covidwho-1266401

ABSTRACT

SARS-CoV-2 infection and the resulting COVID-19 have afflicted millions of people in an ongoing worldwide pandemic. Safe and effective vaccination is needed urgently to protect not only the general population but also vulnerable subjects such as patients with cancer. Currently approved mRNA-based SARS-CoV-2 vaccines seem suitable for patients with cancer based on their mode of action, efficacy, and favorable safety profile reported in the general population. Here, we provide an overview of mRNA-based vaccines including their safety and efficacy. Extrapolating from insights gained from a different preventable viral infection, we review existing data on immunity against influenza A and B vaccines in patients with cancer. Finally, we discuss COVID-19 vaccination in light of the challenges specific to patients with cancer, such as factors that may hinder protective SARS-CoV-2 immune responses in the context of compromised immunity and the use of immune-suppressive or immune-modulating drugs.


Subject(s)
COVID-19 Vaccines , Neoplasms/therapy , RNA, Messenger , SARS-CoV-2/immunology , Viral Vaccines , COVID-19/epidemiology , COVID-19/prevention & control , COVID-19 Vaccines/genetics , COVID-19 Vaccines/therapeutic use , Drug Stability , Humans , Influenza, Human/epidemiology , Influenza, Human/immunology , Influenza, Human/prevention & control , Neoplasms/epidemiology , Neoplasms/immunology , Pandemics , RNA Stability/physiology , RNA, Messenger/administration & dosage , RNA, Messenger/adverse effects , RNA, Messenger/chemistry , RNA, Messenger/genetics , SARS-CoV-2/genetics , Vaccination/methods , Viral Vaccines/adverse effects , Viral Vaccines/chemistry , Viral Vaccines/genetics
14.
Front Immunol ; 12: 641447, 2021.
Article in English | MEDLINE | ID: covidwho-1264330

ABSTRACT

The newly emerged novel coronavirus, SARS-CoV-2, the causative agent of COVID-19 has proven to be a threat to the human race globally, thus, vaccine development against SARS-CoV-2 is an unmet need driving mass vaccination efforts. The receptor binding domain of the spike protein of this coronavirus has multiple neutralizing epitopes and is associated with viral entry. Here we have designed and characterized the SARS-CoV-2 spike protein fragment 330-526 as receptor binding domain 330-526 (RBD330-526) with two native glycosylation sites (N331 and N343); as a potential subunit vaccine candidate. We initially characterized RBD330-526 biochemically and investigated its thermal stability, humoral and T cell immune response of various RBD protein formulations (with or without adjuvant) to evaluate the inherent immunogenicity and immunomodulatory effect. Our result showed that the purified RBD immunogen is stable up to 72 h, without any apparent loss in affinity or specificity of interaction with the ACE2 receptor. Upon immunization in mice, RBD generates a high titer humoral response, elevated IFN-γ producing CD4+ cells, cytotoxic T cells, and robust neutralizing antibodies against live SARS-CoV-2 virus. Our results collectively support the potential of RBD330-526 as a promising vaccine candidate against SARS-CoV-2.


Subject(s)
Antibodies, Viral/blood , COVID-19 Vaccines/administration & dosage , Immunity, Humoral/drug effects , Immunogenicity, Vaccine , Peptide Fragments/administration & dosage , Spike Glycoprotein, Coronavirus/administration & dosage , Th1 Cells/drug effects , Adjuvants, Immunologic/administration & dosage , Animals , Biomarkers/blood , COVID-19 Vaccines/immunology , Chlorocebus aethiops , Drug Stability , Glycosylation , HEK293 Cells , Humans , Immunization , Interferon-gamma/blood , Male , Mice, Inbred C57BL , Peptide Fragments/immunology , Protein Interaction Domains and Motifs , Protein Stability , Spike Glycoprotein, Coronavirus/immunology , Th1 Cells/immunology , Th1 Cells/metabolism , Vaccines, Subunit/administration & dosage , Vaccines, Subunit/immunology , Vero Cells
15.
J Chromatogr B Analyt Technol Biomed Life Sci ; 1176: 122768, 2021 Jun 30.
Article in English | MEDLINE | ID: covidwho-1240421

ABSTRACT

Favipiravir is a broad-spectrum inhibitor of viral RNA polymerase. It is currently used as a possible treatment for coronavirus disease 2019 (COVID-19). Pre-clinical or clinical trials of favipiravir require robust, sensitive, and accurate bioanalytical methods for quantitation of favipiravir levels. Recently, several studies have been reported about developing a validated liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for measuring favipiravir levels. However, these methods were validated predominantly for plasma samples, electrospray ionization was operated only in negative or positive mode, and clinical application of these methods has not been applied for patients with COVID-19. This study aimed was to develop a validated LC-MS/MS method for the measurement of favipiravir levels in positive and negative electrospray ionization mode and to perform a pilot study in patients with COVID-19 receiving favipiravir to demonstrate the applicability of this method in biological samples. Simple protein precipitation was used for the extraction of favipiravir from the desired matrix. Favipiravir levels were quantitated using MS / MS with an electrospray ionization source in positive and negative multiple reaction monitoring (MRM) mode. The chromatographic detection was performed on a reverse-phase Phenomenex C18 column (50 mm × 4.6 mm, 5 µm, 100 Å) with gradient elution using 0.1% formic acid in water and 0.1% formic acid in methanol as mobile phase. The method was linear over the concentration ranges of 0.048-50 µg/mL (in negative ionization mode) and 0.062-50 µg/mL (in positive ionization mode) with a correlation coefficient (r2) better than 0.998. The total run time was 3.5 min. The intra-assay and inter-assay %CV values were less than 7.2% and 8.0%, respectively. A simple, rapid and robust LC-MS / MS method was developed for the measurement of favipiravir and validation studies were performed. The validated method was successfully applied for drug level measurement in COVID-19 patients receiving favipiravir.


Subject(s)
Amides/blood , COVID-19/drug therapy , Chromatography, Liquid/methods , Pyrazines/blood , Tandem Mass Spectrometry/methods , Amides/administration & dosage , Amides/therapeutic use , Antiviral Agents/administration & dosage , Antiviral Agents/blood , Antiviral Agents/therapeutic use , COVID-19/blood , Drug Stability , Humans , Limit of Detection , Pyrazines/administration & dosage , Pyrazines/therapeutic use , Sensitivity and Specificity , Spectrometry, Mass, Electrospray Ionization/methods
18.
Int J Mol Sci ; 22(6)2021 Mar 10.
Article in English | MEDLINE | ID: covidwho-1125145

ABSTRACT

In order to treat Coronavirus Disease 2019 (COVID-19), we predicted and implemented a drug delivery system (DDS) that can provide stable drug delivery through a computational approach including a clustering algorithm and the Schrödinger software. Six carrier candidates were derived by the proposed method that could find molecules meeting the predefined conditions using the molecular structure and its functional group positional information. Then, just one compound named glycyrrhizin was selected as a candidate for drug delivery through the Schrödinger software. Using glycyrrhizin, nafamostat mesilate (NM), which is known for its efficacy, was converted into micelle nanoparticles (NPs) to improve drug stability and to effectively treat COVID-19. The spherical particle morphology was confirmed by transmission electron microscopy (TEM), and the particle size and stability of 300-400 nm were evaluated by measuring DLSand the zeta potential. The loading of NM was confirmed to be more than 90% efficient using the UV spectrum.


Subject(s)
COVID-19/drug therapy , Computational Biology/methods , Drug Delivery Systems/methods , A549 Cells , Anti-Inflammatory Agents/chemistry , Anti-Inflammatory Agents/therapeutic use , Benzamidines/chemistry , Benzamidines/therapeutic use , Cell Survival/drug effects , Cluster Analysis , Computer Simulation , Databases, Pharmaceutical , Drug Carriers/chemistry , Drug Repositioning , Drug Stability , Glycyrrhizic Acid/chemistry , Glycyrrhizic Acid/therapeutic use , Guanidines/chemistry , Guanidines/therapeutic use , Humans , Hydrophobic and Hydrophilic Interactions , Micelles , Microscopy, Electron, Transmission , Molecular Structure , Nanoparticles/chemistry , Particle Size
19.
J Enzyme Inhib Med Chem ; 36(1): 727-736, 2021 Dec.
Article in English | MEDLINE | ID: covidwho-1123193

ABSTRACT

The novel coronavirus disease COVID-19, caused by the virus SARS CoV-2, has exerted a significant unprecedented economic and medical crisis, in addition to its impact on the daily life and health care systems all over the world. Regrettably, no vaccines or drugs are currently available for this new critical emerging human disease. Joining the global fight against COVID-19, in this study we aim at identifying a potential novel inhibitor for SARS COV-2 2'-O-methyltransferase (nsp16) which is one of the most attractive targets in the virus life cycle, responsible for the viral RNA protection via a cap formation process. Firstly, nsp16 enzyme bound to Sinefungin was retrieved from the protein data bank (PDB ID: 6WKQ), then, a 3D pharmacophore model was constructed to be applied to screen 48 Million drug-like compounds of the Zinc database. This resulted in only 24 compounds which were subsequently docked into the enzyme. The best four score-ordered hits from the docking outcome exhibited better scores compared to Sinefungin. Finally, three molecular dynamics (MD) simulation experiments for 150 ns were carried out as a refinement step for our proposed approach. The MD and MM-PBSA outputs revealed compound 11 as the best potential nsp16 inhibitor herein identified, as it displayed a better stability and average binding free energy for the ligand-enzyme complex compared to Sinefungin.


Subject(s)
Antiviral Agents/chemistry , Enzyme Inhibitors/chemistry , SARS-CoV-2/enzymology , Viral Nonstructural Proteins/chemistry , Adenosine/analogs & derivatives , Adenosine/chemistry , Adenosine/metabolism , Antiviral Agents/metabolism , Binding Sites , Crystallography, X-Ray , Databases, Pharmaceutical , Databases, Protein , Drug Stability , Enzyme Inhibitors/metabolism , High-Throughput Screening Assays , Humans , Kinetics , Methyltransferases , Molecular Docking Simulation , Molecular Dynamics Simulation , Protein Binding , Protein Conformation, alpha-Helical , Protein Conformation, beta-Strand , Protein Interaction Domains and Motifs , SARS-CoV-2/chemistry , Thermodynamics , Viral Nonstructural Proteins/antagonists & inhibitors
20.
Bioorg Med Chem Lett ; 40: 127906, 2021 05 15.
Article in English | MEDLINE | ID: covidwho-1118337

ABSTRACT

Zika virus has emerged as a potential threat to human health globally. A previous drug repurposing screen identified the approved anthelminthic drug niclosamide as a small molecule inhibitor of Zika virus infection. However, as antihelminthic drugs are generally designed to have low absorption when dosed orally, the very limited bioavailability of niclosamide will likely hinder its potential direct repurposing as an antiviral medication. Here, we conducted SAR studies focusing on the anilide and salicylic acid regions of niclosamide to improve physicochemical properties such as microsomal metabolic stability, permeability and solubility. We found that the 5-bromo substitution in the salicylic acid region retains potency while providing better drug-like properties. Other modifications in the anilide region with 2'-OMe and 2'-H substitutions were also advantageous. We found that the 4'-NO2 substituent can be replaced with a 4'-CN or 4'-CF3 substituents. Together, these modifications provide a basis for optimizing the structure of niclosamide to improve systemic exposure for application of niclosamide analogs as drug lead candidates for treating Zika and other viral infections. Indeed, key analogs were also able to rescue cells from the cytopathic effect of SARS-CoV-2 infection, indicating relevance for therapeutic strategies targeting the COVID-19 pandemic.


Subject(s)
Antiviral Agents/pharmacology , Niclosamide/analogs & derivatives , Niclosamide/pharmacology , SARS-CoV-2/drug effects , Zika Virus/drug effects , Animals , Antiviral Agents/chemical synthesis , Antiviral Agents/metabolism , Binding Sites , Chlorocebus aethiops , Drug Stability , Humans , Microbial Sensitivity Tests , Microsomes, Liver/metabolism , Molecular Docking Simulation , Molecular Structure , Niclosamide/metabolism , Protein Binding , Rats , Serine Endopeptidases/chemistry , Serine Endopeptidases/metabolism , Structure-Activity Relationship , Vero Cells , Viral Nonstructural Proteins/chemistry , Viral Nonstructural Proteins/metabolism , Viral Proteins/chemistry , Viral Proteins/metabolism
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