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1.
Sci Rep ; 11(1): 24392, 2021 12 22.
Article in English | MEDLINE | ID: covidwho-1585793

ABSTRACT

Most public health measures to contain the COVID-19 pandemic are based on preventing the pathogen spread, and the use of oral antiseptics has been proposed as a strategy to reduce transmission risk. The aim of this manuscript is to test the efficacy of mouthwashes to reduce salivary viral load in vivo. This is a multi-centre, blinded, parallel-group, placebo-controlled randomised clinical trial that tests the effect of four mouthwashes (cetylpyridinium chloride, chlorhexidine, povidone-iodine and hydrogen peroxide) in SARS-CoV-2 salivary load measured by qPCR at baseline and 30, 60 and 120 min after the mouthrinse. A fifth group of patients used distilled water mouthrinse as a control. Eighty-four participants were recruited and divided into 12-15 per group. There were no statistically significant changes in salivary viral load after the use of the different mouthwashes. Although oral antiseptics have shown virucidal effects in vitro, our data show that salivary viral load in COVID-19 patients was not affected by the tested treatments. This could reflect that those mouthwashes are not effective in vivo, or that viral particles are not infective but viral RNA is still detected by PCR. Viral infectivity studies after the use of mouthwashes are therefore required. ( https://clinicaltrials.gov/ct2/show/NCT04707742 ; Identifier: NCT04707742).


Subject(s)
Anti-Infective Agents, Local/pharmacology , Mouthwashes/pharmacology , SARS-CoV-2/drug effects , Saliva/virology , Adolescent , Adult , Aged , Anti-Infective Agents, Local/chemistry , COVID-19/prevention & control , COVID-19/virology , Child , Child, Preschool , Double-Blind Method , Female , Humans , Infant , Infant, Newborn , Male , Middle Aged , Mouthwashes/chemistry , Placebo Effect , SARS-CoV-2/isolation & purification , Viral Load/drug effects , Young Adult
2.
J Acquir Immune Defic Syndr ; 88(3): 299-304, 2021 11 01.
Article in English | MEDLINE | ID: covidwho-1574388

ABSTRACT

BACKGROUND: We assessed the impact of the coronavirus disease 2019 (COVID-19) pandemic on HIV suppression rates in people living with HIV (PLWH) attending a large Italian HIV clinic. SETTING: The HIV outpatient clinic of the Infectious Diseases Department of Luigi Sacco Hospital, Milan, Italy, which serves more than 5000 PLWH per year. METHODS: A before and after quasi-experimental study design was used to make a retrospective assessment of the monthly trend of HIV-RNA determinations of ≥50 among the PLWH attending our clinic, with "before" being the period from January 1, 2016 to February 20, 2020, and "after" being the period from February 21, 2020 to December 31, 2020 (the COVID-19 period). Interrupted time series analysis was used to evaluate any changes in the trend. RESULTS: During the study period, 70,349 HIV-RNA viral load determinations were made, and the percentage of HIV-RNA viral load determinations of <50 copies/mL increased from 88.4% in 2016 to 93.2% in 2020 (P < 0.0001). There was a significant monthly trend toward a decrease in the number of HIV-RNA determinations of ≥50 copies/mL before the pandemic (ß -0.084; standard error 0.015; P < 0.001), and this did not significantly change after it started (ß -0.039, standard error 0.161; P = 0.811). CONCLUSIONS: A high prevalence of viral suppression was maintained among the PLWH referring to our clinic, despite the structural barriers raised by the COVID-19 pandemic. The use of simplified methods of delivering care (such as teleconsultations and multiple antiretroviral treatment prescriptions) may have contributed to preserving this continuum.


Subject(s)
Anti-HIV Agents/therapeutic use , COVID-19/complications , COVID-19/epidemiology , HIV Infections/complications , HIV Infections/epidemiology , Ambulatory Care Facilities , Anti-HIV Agents/administration & dosage , Delivery of Health Care/methods , HIV Infections/drug therapy , HIV-1 , Humans , Italy/epidemiology , RNA, Viral/blood , SARS-CoV-2 , Viral Load/drug effects
4.
Ann Intern Med ; 174(9): 1261-1269, 2021 09.
Article in English | MEDLINE | ID: covidwho-1547664

ABSTRACT

BACKGROUND: New treatment modalities are urgently needed for patients with COVID-19. The World Health Organization (WHO) Solidarity trial showed no effect of remdesivir or hydroxychloroquine (HCQ) on mortality, but the antiviral effects of these drugs are not known. OBJECTIVE: To evaluate the effects of remdesivir and HCQ on all-cause, in-hospital mortality; the degree of respiratory failure and inflammation; and viral clearance in the oropharynx. DESIGN: NOR-Solidarity is an independent, add-on, randomized controlled trial to the WHO Solidarity trial that included biobanking and 3 months of clinical follow-up (ClinicalTrials.gov: NCT04321616). SETTING: 23 hospitals in Norway. PATIENTS: Eligible patients were adults hospitalized with confirmed SARS-CoV-2 infection. INTERVENTION: Between 28 March and 4 October 2020, a total of 185 patients were randomly assigned and 181 were included in the full analysis set. Patients received remdesivir (n = 42), HCQ (n = 52), or standard of care (SoC) (n = 87). MEASUREMENTS: In addition to the primary end point of WHO Solidarity, study-specific outcomes were viral clearance in oropharyngeal specimens, the degree of respiratory failure, and inflammatory variables. RESULTS: No significant differences were seen between treatment groups in mortality during hospitalization. There was a marked decrease in SARS-CoV-2 load in the oropharynx during the first week overall, with similar decreases and 10-day viral loads among the remdesivir, HCQ, and SoC groups. Remdesivir and HCQ did not affect the degree of respiratory failure or inflammatory variables in plasma or serum. The lack of antiviral effect was not associated with symptom duration, level of viral load, degree of inflammation, or presence of antibodies against SARS-CoV-2 at hospital admittance. LIMITATION: The trial had no placebo group. CONCLUSION: Neither remdesivir nor HCQ affected viral clearance in hospitalized patients with COVID-19. PRIMARY FUNDING SOURCE: National Clinical Therapy Research in the Specialist Health Services, Norway.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/therapeutic use , COVID-19/drug therapy , COVID-19/virology , Hydroxychloroquine/therapeutic use , Viral Load/drug effects , Adenosine Monophosphate/therapeutic use , Alanine/therapeutic use , Antibodies, Viral/blood , Biomarkers/blood , COVID-19/complications , COVID-19/mortality , Cause of Death , Female , Hospital Mortality , Humans , Inflammation/virology , Male , Middle Aged , Norway/epidemiology , Oropharynx/virology , Respiratory Insufficiency/virology , SARS-CoV-2/immunology , Severity of Illness Index , Standard of Care , Treatment Outcome
5.
Microbiol Spectr ; 9(2): e0135221, 2021 10 31.
Article in English | MEDLINE | ID: covidwho-1526454

ABSTRACT

The emerging new lineages of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) have marked a new phase of coronavirus disease 2019 (COVID-19). Understanding the recognition mechanisms of potent neutralizing monoclonal antibodies (NAbs) against the spike protein is pivotal for developing new vaccines and antibody drugs. Here, we isolated several monoclonal antibodies (MAbs) against the SARS-CoV-2 spike protein receptor-binding domain (S-RBD) from the B cell receptor repertoires of a SARS-CoV-2 convalescent. Among these MAbs, the antibody nCoV617 demonstrates the most potent neutralizing activity against authentic SARS-CoV-2 infection, as well as prophylactic and therapeutic efficacies against the human angiotensin-converting enzyme 2 (ACE2) transgenic mouse model in vivo. The crystal structure of S-RBD in complex with nCoV617 reveals that nCoV617 mainly binds to the back of the "ridge" of RBD and shares limited binding residues with ACE2. Under the background of the S-trimer model, it potentially binds to both "up" and "down" conformations of S-RBD. In vitro mutagenesis assays show that mutant residues found in the emerging new lineage B.1.1.7 of SARS-CoV-2 do not affect nCoV617 binding to the S-RBD. These results provide a new human-sourced neutralizing antibody against the S-RBD and assist vaccine development. IMPORTANCE COVID-19 is a respiratory disease caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). The COVID-19 pandemic has posed a serious threat to global health and the economy, so it is necessary to find safe and effective antibody drugs and treatments. The receptor-binding domain (RBD) in the SARS-CoV-2 spike protein is responsible for binding to the angiotensin-converting enzyme 2 (ACE2) receptor. It contains a variety of dominant neutralizing epitopes and is an important antigen for the development of new coronavirus antibodies. The significance of our research lies in the determination of new epitopes, the discovery of antibodies against RBD, and the evaluation of the antibodies' neutralizing effect. The identified antibodies here may be drug candidates for the development of clinical interventions for SARS-CoV-2.


Subject(s)
Antibodies, Neutralizing/therapeutic use , Antibodies, Viral/therapeutic use , COVID-19/therapy , SARS-CoV-2/immunology , Spike Glycoprotein, Coronavirus/immunology , Angiotensin-Converting Enzyme 2/antagonists & inhibitors , Angiotensin-Converting Enzyme 2/genetics , Angiotensin-Converting Enzyme 2/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing/immunology , Antibodies, Neutralizing/metabolism , Antibodies, Viral/immunology , Antibodies, Viral/metabolism , Binding Sites/immunology , COVID-19 Vaccines/immunology , Crystallography, X-Ray , Disease Models, Animal , Female , Humans , Immunization, Passive/methods , Immunoglobulin G/blood , Mice , Mice, Inbred C57BL , Mice, Transgenic , Protein Interaction Domains and Motifs/immunology , Viral Load/drug effects
6.
Nat Commun ; 12(1): 6304, 2021 11 02.
Article in English | MEDLINE | ID: covidwho-1500462

ABSTRACT

Accumulating mutations in the SARS-CoV-2 Spike (S) protein can increase the possibility of immune escape, challenging the present COVID-19 prophylaxis and clinical interventions. Here, 3 receptor binding domain (RBD) specific monoclonal antibodies (mAbs), 58G6, 510A5 and 13G9, with high neutralizing potency blocking authentic SARS-CoV-2 virus display remarkable efficacy against authentic B.1.351 virus. Surprisingly, structural analysis has revealed that 58G6 and 13G9 both recognize the steric region S470-495 on the RBD, overlapping the E484K mutation presented in B.1.351. Also, 58G6 directly binds to another region S450-458 in the RBD. Significantly, 58G6 and 510A5 both demonstrate prophylactic efficacy against authentic SARS-CoV-2 and B.1.351 viruses in the transgenic mice expressing human ACE2 (hACE2), protecting weight loss and reducing virus loads. Together, we have evidenced 2 potent neutralizing Abs with unique mechanism targeting authentic SARS-CoV-2 mutants, which can be promising candidates to fulfill the urgent needs for the prolonged COVID-19 pandemic.


Subject(s)
Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/prevention & control , SARS-CoV-2/immunology , Animals , Antibodies, Monoclonal/administration & dosage , Antibodies, Monoclonal/chemistry , Antibodies, Monoclonal/immunology , Antibodies, Neutralizing/administration & dosage , Antibodies, Neutralizing/chemistry , Antibodies, Viral/administration & dosage , Antibodies, Viral/chemistry , Binding Sites , COVID-19/pathology , COVID-19/virology , Epitopes , Humans , Mice , Mice, Transgenic , Mutation , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Viral Load/drug effects , Weight Loss/drug effects
8.
Sci Rep ; 11(1): 20012, 2021 10 08.
Article in English | MEDLINE | ID: covidwho-1462029

ABSTRACT

There are currently no cures for coronavirus infections, making the prevention of infections the only course open at the present time. The COVID-19 pandemic has been difficult to prevent, as the infection is spread by respiratory droplets and thus effective, scalable and safe preventive interventions are urgently needed. We hypothesise that preventing viral entry into mammalian nasal epithelial cells may be one way to limit the spread of COVID-19. Here we show that N-palmitoyl-N-monomethyl-N,N-dimethyl-N,N,N-trimethyl-6-O-glycolchitosan (GCPQ), a positively charged polymer that has been through an extensive Good Laboratory Practice toxicology screen, is able to reduce the infectivity of SARS-COV-2 in A549ACE2+ and Vero E6 cells with a log removal value of - 3 to - 4 at a concentration of 10-100 µg/ mL (p < 0.05 compared to untreated controls) and to limit infectivity in human airway epithelial cells at a concentration of 500 µg/ mL (p < 0.05 compared to untreated controls). In vivo studies using transgenic mice expressing the ACE-2 receptor, dosed nasally with SARS-COV-2 (426,000 TCID50/mL) showed a trend for nasal GCPQ (20 mg/kg) to inhibit viral load in the respiratory tract and brain, although the study was not powered to detect statistical significance. GCPQ's electrostatic binding to the virus, preventing viral entry into the host cells, is the most likely mechanism of viral inhibition. Radiolabelled GCPQ studies in mice show that at a dose of 10 mg/kg, GCPQ has a long residence time in mouse nares, with 13.1% of the injected dose identified from SPECT/CT in the nares, 24 h after nasal dosing. With a no observed adverse effect level of 18 mg/kg in rats, following a 28-day repeat dose study, clinical testing of this polymer, as a COVID-19 prophylactic is warranted.


Subject(s)
Antiviral Agents/therapeutic use , COVID-19/drug therapy , Nasal Sprays , SARS-CoV-2/drug effects , A549 Cells , Animals , Antiviral Agents/administration & dosage , Chlorocebus aethiops , Humans , Male , Methylation , Mice, Inbred BALB C , Mice, Transgenic , SARS-CoV-2/physiology , Surface-Active Agents/administration & dosage , Surface-Active Agents/therapeutic use , Vero Cells , Viral Load/drug effects
9.
Clin Microbiol Infect ; 27(10): 1494-1501, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1454090

ABSTRACT

OBJECTIVES: To determine if commercially available mouthwash with ß-cyclodextrin and citrox (bioflavonoids) (CDCM) could decrease the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) salivary viral load. METHODS: In this randomized controlled trial, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) PCR-positive patients aged 18-85 years with asymptomatic to mild coronavirus disease 2019 (COVID-19) symptoms for <8 days were recruited. A total of 176 eligible patients were randomly assigned (1:1) to CDCM or placebo. Three rinses daily were performed for 7 days. Saliva sampling was performed on day 1 at 09.00 (T1), 13.00 (T2) and 18.00 (T3). On the following 6 days, one sample was taken at 15.00. Quantitative RT-PCR was used to detect SARS-CoV-2. RESULTS: The intention-to-treat analysis demonstrated that, over the course of 1 day, CDCM was significantly more effective than placebo 4 hours after the first dose (p 0.036), with a median percentage (log10 copies/mL) decrease T1-T2 of -12.58% (IQR -29.55% to -0.16%). The second dose maintained the low median value for the CDCM (3.08 log10 copies/mL; IQR 0-4.19), compared with placebo (3.31 log10 copies/mL; IQR 1.18-4.75). At day 7, there was still a greater median percentage (log10 copies/mL) decrease in salivary viral load over time in the CDCM group (-58.62%; IQR -100% to -34.36%) compared with the placebo group (-50.62%; IQR -100% to -27.66%). These results were confirmed by the per-protocol analysis. CONCLUSIONS: This trial supports the relevance of using CDCM on day 1 (4 hours after the initial dose) to reduce the SARS-CoV-2 viral load in saliva. For long-term effect (7 days), CDMC appears to provide a modest benefit compared with placebo in reducing viral load in saliva.


Subject(s)
Antiviral Agents/therapeutic use , COVID-19/prevention & control , Mouthwashes/therapeutic use , SARS-CoV-2/drug effects , Adolescent , Adult , Aged , Antiviral Agents/chemistry , Asymptomatic Infections , COVID-19/transmission , Double-Blind Method , Female , Flavonoids/analysis , Flavonoids/therapeutic use , Humans , Intention to Treat Analysis , Male , Middle Aged , Mouthwashes/chemistry , SARS-CoV-2/isolation & purification , Saliva/virology , Viral Load/drug effects , Young Adult , beta-Cyclodextrins/analysis , beta-Cyclodextrins/therapeutic use
10.
Sci Rep ; 11(1): 19458, 2021 09 30.
Article in English | MEDLINE | ID: covidwho-1447326

ABSTRACT

Efficacious therapeutics for Ebola virus disease are in great demand. Ebola virus infections mediated by mucosal exposure, and aerosolization in particular, present a novel challenge due to nontypical massive early infection of respiratory lymphoid tissues. We performed a randomized and blinded study to compare outcomes from vehicle-treated and remdesivir-treated rhesus monkeys in a lethal model of infection resulting from aerosolized Ebola virus exposure. Remdesivir treatment initiated 4 days after exposure was associated with a significant survival benefit, significant reduction in serum viral titer, and improvements in clinical pathology biomarker levels and lung histology compared to vehicle treatment. These observations indicate that remdesivir may have value in countering aerosol-induced Ebola virus disease.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antiviral Agents/pharmacology , Ebolavirus/drug effects , Hemorrhagic Fever, Ebola/drug therapy , Adenosine Monophosphate/administration & dosage , Adenosine Monophosphate/pharmacology , Administration, Intravenous , Aerosols , Alanine/administration & dosage , Alanine/pharmacology , Animals , Antiviral Agents/administration & dosage , Disease Models, Animal , Female , Hemorrhagic Fever, Ebola/blood , Kaplan-Meier Estimate , Liver/drug effects , Liver/virology , Lung/pathology , Lung/virology , Lymph Nodes/drug effects , Lymph Nodes/pathology , Lymph Nodes/virology , Macaca mulatta , Male , Random Allocation , Systemic Inflammatory Response Syndrome/drug therapy , Systemic Inflammatory Response Syndrome/virology , Viral Load/drug effects , Viremia/drug therapy
11.
Jpn J Infect Dis ; 74(5): 421-423, 2021 Sep 22.
Article in English | MEDLINE | ID: covidwho-1436359

ABSTRACT

Green tea extracts effectively inactivated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in vitro in a dose-dependent manner. Ten-fold serially diluted solutions of catechin mixture reagent from green tea were mixed with the viral culture fluid at a volume ratio of 9:1, respectively, and incubated at room temperature for 5 min. The solution of 10 mg/mL catechin reagent reduced the viral titer by 4.2 log and 1.0 mg/mL solution by one log. Pre-infection treatment of cells with the reagent alone did not affect viral growth. In addition, cells treated with only the reagent were assayed for host cell viability using the WST-8 system, and almost no host cell damage by the treatment was observed. These findings suggested that the direct treatment of virus with the reagent before inoculation decreased the viral activity and that catechins might have the potential to suppress SARSCoV-2 infection.


Subject(s)
Antiviral Agents/pharmacology , Catechin/pharmacology , SARS-CoV-2/drug effects , Tea/chemistry , Animals , COVID-19/virology , Cell Survival/drug effects , Chlorocebus aethiops , Dose-Response Relationship, Drug , Humans , Vero Cells , Viral Load/drug effects
12.
Jpn J Infect Dis ; 74(5): 416-420, 2021 Sep 22.
Article in English | MEDLINE | ID: covidwho-1436358

ABSTRACT

We retrospectively studied nasopharyngeal severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) viral load in coronavirus disease 2019 (COVID-19) patients who were hospitalized between January 13 and April 1, 2020. Quantitative real-time reverse transcription-polymerase chain reaction (RT-PCR) was conducted using primers and probes targeting the ORF1ab and N genes. All patients were classified in the following groups: Group 1: received favipiravir + chloroquine or hydroxychloroquine + lopinavir/ritonavir or darunavir/ritonavir for 5-10 days, Group 2: received chloroquine or hydroxychloroquine + lopinavir/ritonavir or darunavir/ritonavir for 5-10 days, and Group 3: no antiviral medication. Among the 115 patients, 38 (33%), 54 (47%), and 23 (20%) were in Groups 1, 2, and 3, respectively. The median (IQR) baseline viral loads on day 0 of Groups 1, 2, and 3 were 7.2 (6.0-8.1), 6.9 (5.8-7.8), and 6.9 (5.8-7.6) log10 copies/mL, respectively. The reductions of mean viral loads on day 3 from baseline were 2.41, 1.38, and 2.19 log10 copies/mL in the corresponding groups (P < 0.05). There were no differences in the reduction of mean viral loads from baseline among the three groups on days 5 and 10 (P > 0.05). Multiple logistic regression analysis showed that receiving favipiravir was associated with nasopharyngeal viral load reduction at three days (P = 0.001). Significant nasopharyngeal SARS-CoV-2 viral load reduction was achieved in COVID-19 patients who received a favipiravir-containing regimen.


Subject(s)
Amides/therapeutic use , Antiviral Agents/therapeutic use , COVID-19/drug therapy , Pyrazines/therapeutic use , SARS-CoV-2/drug effects , Viral Load/drug effects , Adult , COVID-19/diagnosis , COVID-19/virology , Drug Therapy, Combination , Female , Hospitalization , Humans , Male , Middle Aged , Nasopharynx , Retrospective Studies , SARS-CoV-2/isolation & purification , Treatment Outcome
13.
Viruses ; 13(8)2021 08 12.
Article in English | MEDLINE | ID: covidwho-1436097

ABSTRACT

Type III interferons (lambda IFNs) are a quite new, small family of three closely related cytokines with interferon-like activity. Attention to IFN-λ is mainly focused on direct antiviral activity in which, as with IFN-α, viral genome replication is inhibited without the participation of immune system cells. The heterodimeric receptor for lambda interferons is exposed mainly on epithelial cells, which limits its possible action on other cells, thus reducing the likelihood of developing undesirable side effects compared to type I IFN. In this study, we examined the antiviral potential of exogenous human IFN-λ1 in cellular models of viral infection. To study the protective effects of IFN-λ1, three administration schemes were used: 'preventive' (pretreatment); 'preventive/therapeutic' (pre/post); and 'therapeutic' (post). Three IFN-λ1 concentrations (from 10 to 500 ng/mL) were used. We have shown that human IFN-λ1 restricts SARS-CoV-2 replication in Vero cells with all three treatment schemes. In addition, we have shown a decrease in the viral loads of CHIKV and IVA with the 'preventive' and 'preventive/therapeutic' regimes. No significant antiviral effect of IFN-λ1 against AdV was detected. Our study highlights the potential for using IFN-λ as a broad-spectrum therapeutic agent against respiratory RNA viruses.


Subject(s)
Adenoviruses, Human/drug effects , Chikungunya virus/drug effects , Influenza A virus/drug effects , Interferons/pharmacology , SARS-CoV-2/drug effects , A549 Cells , Adenoviruses, Human/physiology , Animals , Chikungunya virus/physiology , Chlorocebus aethiops , Dose-Response Relationship, Drug , Gene Expression Regulation , Humans , Influenza A virus/physiology , Interferons/therapeutic use , Interleukins , RNA Virus Infections/drug therapy , RNA Virus Infections/prevention & control , Recombinant Proteins/pharmacology , SARS-CoV-2/physiology , Vero Cells , Viral Load/drug effects , Virus Replication/drug effects
14.
Int J Mol Sci ; 22(18)2021 Sep 17.
Article in English | MEDLINE | ID: covidwho-1430892

ABSTRACT

Previous studies reported on the broad-spectrum antiviral function of heparin. Here we investigated the antiviral function of magnesium-modified heparin and found that modified heparin displayed a significantly enhanced antiviral function against human adenovirus (HAdV) in immortalized and primary cells. Nuclear magnetic resonance analyses revealed a conformational change of heparin when complexed with magnesium. To broadly explore this discovery, we tested the antiviral function of modified heparin against herpes simplex virus type 1 (HSV-1) and found that the replication of HSV-1 was even further decreased compared to aciclovir. Moreover, we investigated the antiviral effect against the new severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) and measured a 55-fold decreased viral load in the supernatant of infected cells associated with a 38-fold decrease in virus growth. The advantage of our modified heparin is an increased antiviral effect compared to regular heparin.


Subject(s)
Antiviral Agents/pharmacology , Heparin/pharmacology , Magnesium Chloride/pharmacology , Acyclovir/pharmacology , Adenoviruses, Human/drug effects , Adenoviruses, Human/physiology , Animals , Antiviral Agents/chemistry , CHO Cells , Cell Line, Tumor , Chlorocebus aethiops , Cricetulus , Drug Evaluation, Preclinical , Fibroblasts , Heparin/chemistry , Herpesvirus 1, Human/drug effects , Herpesvirus 1, Human/physiology , Humans , Magnesium Chloride/chemistry , Magnetic Resonance Spectroscopy , Microbial Sensitivity Tests , Molecular Structure , Primary Cell Culture , SARS-CoV-2/drug effects , SARS-CoV-2/physiology , Structure-Activity Relationship , Vero Cells , Viral Load/drug effects , Virus Replication/drug effects
16.
J Virol ; 95(22): e0112621, 2021 10 27.
Article in English | MEDLINE | ID: covidwho-1398575

ABSTRACT

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged at the end of 2019 and has been responsible for the still ongoing coronavirus disease 2019 (COVID-19) pandemic. Prophylactic vaccines have been authorized by the U.S. Food and Drug Administration (FDA) for the prevention of COVID-19. Identification of SARS-CoV-2-neutralizing antibodies (NAbs) is important to assess vaccine protection efficacy, including their ability to protect against emerging SARS-CoV-2 variants of concern (VoC). Here, we report the generation and use of a recombinant (r)SARS-CoV-2 USA/WA1/2020 (WA-1) strain expressing Venus and an rSARS-CoV-2 strain expressing mCherry and containing mutations K417N, E484K, and N501Y found in the receptor binding domain (RBD) of the spike (S) glycoprotein of the South African (SA) B.1.351 (beta [ß]) VoC in bifluorescent-based assays to rapidly and accurately identify human monoclonal antibodies (hMAbs) able to neutralize both viral infections in vitro and in vivo. Importantly, our bifluorescent-based system accurately recapitulated findings observed using individual viruses. Moreover, fluorescent-expressing rSARS-CoV-2 strain and the parental wild-type (WT) rSARS-CoV-2 WA-1 strain had similar viral fitness in vitro, as well as similar virulence and pathogenicity in vivo in the K18 human angiotensin-converting enzyme 2 (hACE2) transgenic mouse model of SARS-CoV-2 infection. We demonstrate that these new fluorescent-expressing rSARS-CoV-2 can be used in vitro and in vivo to easily identify hMAbs that simultaneously neutralize different SARS-CoV-2 strains, including VoC, for the rapid assessment of vaccine efficacy or the identification of prophylactic and/or therapeutic broadly NAbs for the treatment of SARS-CoV-2 infection. IMPORTANCE SARS-CoV-2 is responsible of the COVID-19 pandemic that has warped daily routines and socioeconomics. There is still an urgent need for prophylactics and therapeutics to treat SARS-CoV-2 infections. In this study, we demonstrate the feasibility of using bifluorescent-based assays for the rapid identification of hMAbs with neutralizing activity against SARS-CoV-2, including VoC in vitro and in vivo. Importantly, results obtained with these bifluorescent-based assays recapitulate those observed with individual viruses, demonstrating their feasibility to rapidly advance our understanding of vaccine efficacy and to identify broadly protective human NAbs for the therapeutic treatment of SARS-CoV-2.


Subject(s)
Antibodies, Neutralizing/immunology , Neutralization Tests/methods , SARS-CoV-2/immunology , Animals , Antibodies, Monoclonal/immunology , Antibodies, Monoclonal/therapeutic use , Antibodies, Neutralizing/therapeutic use , Broadly Neutralizing Antibodies/immunology , Broadly Neutralizing Antibodies/therapeutic use , COVID-19/therapy , COVID-19/virology , Genes, Reporter , Humans , Luminescent Proteins/genetics , Luminescent Proteins/metabolism , Lung/drug effects , Lung/virology , Mice , Mutation , Recombinant Proteins/genetics , Recombinant Proteins/immunology , Recombinant Proteins/metabolism , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Spike Glycoprotein, Coronavirus/metabolism , Viral Load/drug effects , Virus Replication/drug effects
17.
Future Microbiol ; 16: 119-130, 2021 01.
Article in English | MEDLINE | ID: covidwho-1389070

ABSTRACT

A review of nasal sprays and gargles with antiviral properties suggests that a number of commonly used antiseptics including povidone-iodine, Listerine®, iota-carrageenan and chlorhexidine should be studied in clinical trials to mitigate both the progression and transmission of SARS-CoV-2. Several of these antiseptics have demonstrated the ability to cut the viral load of SARS-CoV-2 by 3-4 log10 in 15-30 s in vitro. In addition, hypertonic saline targets viral replication by increasing hypochlorous acid inside the cell. A number of clinical trials are in process to study these interventions both for prevention of transmission, prophylaxis after exposure, and to diminish progression by reduction of viral load in the early stages of infection.


Subject(s)
Anti-Infective Agents, Local/administration & dosage , Anti-Infective Agents, Local/therapeutic use , COVID-19/prevention & control , SARS-CoV-2/drug effects , COVID-19/transmission , Carrageenan/therapeutic use , Chlorhexidine/therapeutic use , Drug Combinations , Hydrogen Peroxide/therapeutic use , Nasal Sprays , Oils, Volatile/therapeutic use , Povidone-Iodine/therapeutic use , Salicylates/therapeutic use , Terpenes/therapeutic use , Viral Load/drug effects
19.
Nature ; 592(7853): 277-282, 2021 04.
Article in English | MEDLINE | ID: covidwho-1387425

ABSTRACT

The spike protein of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is critical for virus infection through the engagement of the human ACE2 protein1 and is a major antibody target. Here we show that chronic infection with SARS-CoV-2 leads to viral evolution and reduced sensitivity to neutralizing antibodies in an immunosuppressed individual treated with convalescent plasma, by generating whole-genome ultra-deep sequences for 23 time points that span 101 days and using in vitro techniques to characterize the mutations revealed by sequencing. There was little change in the overall structure of the viral population after two courses of remdesivir during the first 57 days. However, after convalescent plasma therapy, we observed large, dynamic shifts in the viral population, with the emergence of a dominant viral strain that contained a substitution (D796H) in the S2 subunit and a deletion (ΔH69/ΔV70) in the S1 N-terminal domain of the spike protein. As passively transferred serum antibodies diminished, viruses with the escape genotype were reduced in frequency, before returning during a final, unsuccessful course of convalescent plasma treatment. In vitro, the spike double mutant bearing both ΔH69/ΔV70 and D796H conferred modestly decreased sensitivity to convalescent plasma, while maintaining infectivity levels that were similar to the wild-type virus.The spike substitution mutant D796H appeared to be the main contributor to the decreased susceptibility to neutralizing antibodies, but this mutation resulted in an infectivity defect. The spike deletion mutant ΔH69/ΔV70 had a twofold higher level of infectivity than wild-type SARS-CoV-2, possibly compensating for the reduced infectivity of the D796H mutation. These data reveal strong selection on SARS-CoV-2 during convalescent plasma therapy, which is associated with the emergence of viral variants that show evidence of reduced susceptibility to neutralizing antibodies in immunosuppressed individuals.


Subject(s)
COVID-19/drug therapy , COVID-19/therapy , COVID-19/virology , Evolution, Molecular , Mutagenesis/drug effects , SARS-CoV-2/drug effects , SARS-CoV-2/genetics , Adenosine Monophosphate/analogs & derivatives , Adenosine Monophosphate/pharmacology , Adenosine Monophosphate/therapeutic use , Aged , Alanine/analogs & derivatives , Alanine/pharmacology , Alanine/therapeutic use , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , COVID-19/immunology , Chronic Disease , Genome, Viral/drug effects , Genome, Viral/genetics , High-Throughput Nucleotide Sequencing , Humans , Immune Evasion/drug effects , Immune Evasion/genetics , Immune Evasion/immunology , Immune Tolerance/drug effects , Immune Tolerance/immunology , Immunization, Passive , Male , Mutant Proteins/chemistry , Mutant Proteins/genetics , Mutant Proteins/immunology , Mutation , Phylogeny , SARS-CoV-2/immunology , SARS-CoV-2/metabolism , Spike Glycoprotein, Coronavirus/chemistry , Spike Glycoprotein, Coronavirus/genetics , Spike Glycoprotein, Coronavirus/immunology , Time Factors , Viral Load/drug effects , Virus Shedding
20.
Nat Commun ; 12(1): 1891, 2021 03 25.
Article in English | MEDLINE | ID: covidwho-1387333

ABSTRACT

Monoclonal antibodies (mAbs) and remdesivir, a small-molecule antiviral, are promising monotherapies for many viruses, including members of the genera Marburgvirus and Ebolavirus (family Filoviridae), and more recently, SARS-CoV-2. One of the major challenges of acute viral infections is the treatment of advanced disease. Thus, extending the window of therapeutic intervention is critical. Here, we explore the benefit of combination therapy with a mAb and remdesivir in a non-human primate model of Marburg virus (MARV) disease. While rhesus monkeys are protected against lethal infection when treatment with either a human mAb (MR186-YTE; 100%), or remdesivir (80%), is initiated 5 days post-inoculation (dpi) with MARV, no animals survive when either treatment is initiated alone beginning 6 dpi. However, by combining MR186-YTE with remdesivir beginning 6 dpi, significant protection (80%) is achieved, thereby extending the therapeutic window. These results suggest value in exploring combination therapy in patients presenting with advanced filovirus disease.


Subject(s)
Adenosine Monophosphate/analogs & derivatives , Alanine/analogs & derivatives , Antibodies, Monoclonal/therapeutic use , Antibodies, Viral/therapeutic use , Marburg Virus Disease/drug therapy , Marburgvirus/drug effects , Adenosine Monophosphate/therapeutic use , Alanine/therapeutic use , Animals , Disease Models, Animal , Drug Therapy, Combination , Macaca mulatta , Marburg Virus Disease/prevention & control , Viral Load/drug effects
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