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1.
Viruses ; 14(6)2022 05 27.
Article in English | MEDLINE | ID: covidwho-1869816

ABSTRACT

Pyridobenzothiazolone derivatives are a promising class of broad-spectrum antivirals. However, the mode of action of these compounds remains poorly understood. The HeE1-17Y derivative has already been shown to be a potent compound against a variety of flaviviruses of global relevance. In this work, the mode of action of HeE1-17Y has been studied for West Nile virus taking advantage of reporter replication particles (RRPs). Viral infectivity was drastically reduced by incubating the compound with the virus before infection, thus suggesting a direct interaction with the viral particles. Indeed, RRPs incubated with the inhibitor appeared to be severely compromised in electron microscopy analysis. HeE1-17Y is active against other enveloped viruses, including SARS-CoV-2, but not against two non-enveloped viruses, suggesting a virucidal mechanism that involves the alteration of the viral membrane.


Subject(s)
COVID-19 , Flavivirus , RNA Viruses , Viruses , Antiviral Agents/pharmacology , Humans , SARS-CoV-2
2.
Environ Int ; 164: 107272, 2022 06.
Article in English | MEDLINE | ID: covidwho-1814398

ABSTRACT

The current COVID-19 pandemic has highlighted the importance of aerosol-based transmission of human pathogens; this therefore calls for novel medical devices which are able to sterilize contaminated aerosols. Here we describe a new laser device able to sterilize droplets containing either viruses or bacteria. Using engineered viral particles, we determined the 10,600 nm wavelength as the most efficient and exploitable laser source to be manufactured in a commercial device. Given the lack of existing working models to reproduce a human aerosol containing living microbial particles, we developed a new system mimicking human droplet formation and preserving bacterial and viral viability. This evidenced the efficacy of 10,600 nm laser light to kill two aerosol transmitted human pathogens, Legionella pneumophila and SARS-CoV-2. The minimal exposure time of <15 ms was required for the inactivation of over 99% pathogens in the aerosol; this is a key element in the design of a device that is safe and can be used in preventing inter-individual transmission. This represents a major advantage over existing devices, which mainly aim at either purifying incoming air by filters or sterilizing solid surfaces, which are not the major transmission routes for airborne communicable diseases.


Subject(s)
COVID-19 , SARS-CoV-2 , Aerosols , Humans , Lasers , Pandemics , Sterilization
3.
Protein Expr Purif ; 194: 106071, 2022 06.
Article in English | MEDLINE | ID: covidwho-1676879

ABSTRACT

Reliable diagnosis is critical to identify infections of SARS-CoV-2 as well as to evaluate the immune response to virus and vaccines. Consequently, it becomes crucial the isolation of sensitive antibodies to use as immunocapture elements of diagnostic tools. The final bottleneck to achieve these results is the availability of enough antigen of good quality. We have established a robust pipeline for the production of recombinant, functional SARS-CoV-2 Spike receptor binding domain (RBD) at high yield and low cost in culture flasks. RBD was expressed in transiently transfected ExpiCHO cells at 32 °C and 5% CO2 and purified up to 40 mg/L. The progressive protein accumulation in the culture medium was monitored with an immunobinding assay in order to identify the optimal collection time. Successively, a two-step chromatographic protocol enabled its selective purification in the monomeric state. RBD quality assessment was positively evaluated by SDS-PAGE, Western Blotting and Mass Spectrometry, while Bio-Layer Interferometry, flow cytometer and ELISA tests confirmed its functionality. This effective protocol for the RBD production in transient eukaryotic system can be immediately extended to the production of RBD mutants.


Subject(s)
COVID-19 , Spike Glycoprotein, Coronavirus , Antibodies, Viral , Enzyme-Linked Immunosorbent Assay , Humans , Protein Binding , SARS-CoV-2/genetics , Spike Glycoprotein, Coronavirus/chemistry
4.
Microbiol Resour Announc ; 11(2): e0118221, 2022 Feb 17.
Article in English | MEDLINE | ID: covidwho-1673355

ABSTRACT

The coding-complete severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) genome sequences from 15 nasopharyngeal swabs collected in Addis Ababa, Ethiopia, during the period from December 2020 to March 2021 were determined using Illumina MiSeq technology. A sequence analysis identified that the B.1 SARS-CoV-2 lineage was most prevalent with the worrying emergence of B.1.1.7 in June 2021.

5.
COVID ; 1(4):784-789, 2021.
Article in English | MDPI | ID: covidwho-1580970

ABSTRACT

Quick and reliable identification of severe acute respiratory syndrome coronavirus SARS-CoV-2 in the population is required to manage the COVID-19 pandemic. This is a prospective observational study of diagnostic accuracy. Paired swab samples from 317 asymptomatic individuals referring to a drive-in testing facility were tested in parallel by means of the rapid antigen test developed by Jiangsu Bioperfectus Technologies and routine nucleic acid detection. Overall specificity was 100% and sensitivity was 49% but reached 87% at higher viral loads (Ct < 25). In this study, the antigen detection test showed high specificity and good sensitivity in asymptomatic individuals carrying higher viral loads. The assay performance worsened with lower viral loads, making it useful when a rapidly deployable test is essential and to assess a potential risk of immediate transmission in the community, but not recommended for testing asymptomatic individuals.

6.
Microbiol Resour Announc ; 10(47): e0095221, 2021 Nov 24.
Article in English | MEDLINE | ID: covidwho-1532971

ABSTRACT

Here, we report the genome sequences of five severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strains that were obtained from symptomatic individuals with travel histories during community surveillance in the Dominican Republic in 2020. These sequences provide a starting point for further genomic studies of gene flow and molecular diversity in the Caribbean nation. Phylogenetic analysis suggests that all genomes correspond to the B.1 variant.

7.
Med Lav ; 112(5): 331-339, 2021 Oct 28.
Article in English | MEDLINE | ID: covidwho-1498269

ABSTRACT

BACKGROUND: the sensitivity and specificity of a rapid antibody test were investigated for the screening of healthcare workers. METHODS: the serum of 389 health care workers exposed to COVID-19 patients or with symptoms, were analysed. All workers underwent monthly the screening for SARS-CoV-2 with detection of viral RNA in nasopharyngeal swabs by RT-PCR. IgG antibody detection in serum was performed by Chemiluminescence Immunoassay (CLIA) and by the Rapid test (KHB diagnostic kit for SARS CoV-2 IgM/IgG antibody after a median of 7.6 weeks (25°-75° percentiles 6.6-11.5). RESULTS: the rapid test resulted positive in 31/132 (23.5%), 16/135 (11.8%) and 0/122 cases in COVID-19 positive individuals, in those with only SARS-CoV-2 IgG antibodies and in those negative for both tests, respectively. Sensitivity was 17.6% (CI95% 13.2-22.7) and 23.5% (CI95% 16.5-31.6), and specificity was 100% (CI95% 97-100) and 100% (CI95% 97-100) considering Rapid test vs CLIA IgG or Rapid test vs SARS-CoV-2 positive RNA detection, respectively. CONCLUSION: the KHB Rapid test is not suitable for the screening of workers with previous COVID-19 infection.


Subject(s)
COVID-19 , COVID-19 Testing , Health Personnel , Humans , Immunoglobulin G , Immunoglobulin M , SARS-CoV-2 , Sensitivity and Specificity
8.
FEBS J ; 288(17): 4992-4995, 2021 Sep.
Article in English | MEDLINE | ID: covidwho-1393881

ABSTRACT

In this Editorial, we highlight the contents of The FEBS Journal's second Special Issue focussed on COVID-19. The issue covers a variety of aspects related to COVID-19, ranging from the most recent improvements in therapies and the significant impact of rapidly developed COVID-19 vaccines to the emergence of variants of SARS-CoV-2, the role of the immune system in the various stages of the disease and the impact of the disease in different organs. We hope that this collection of articles will give readers an informative and critical perspective on recent advances in understanding and treating COVID-19.


Subject(s)
COVID-19 Vaccines/therapeutic use , COVID-19/epidemiology , SARS-CoV-2/genetics , COVID-19/therapy , COVID-19/virology , Disease Management , Humans , Immune System/immunology , SARS-CoV-2/pathogenicity
9.
Commun Biol ; 4(1): 489, 2021 04 21.
Article in English | MEDLINE | ID: covidwho-1387493

ABSTRACT

We investigated SARS-CoV-2 transmission dynamics in Italy, one of the countries hit hardest by the pandemic, using phylodynamic analysis of viral genetic and epidemiological data. We observed the co-circulation of multiple SARS-CoV-2 lineages over time, which were linked to multiple importations and characterized by large transmission clusters concomitant with a high number of infections. Subsequent implementation of a three-phase nationwide lockdown strategy greatly reduced infection numbers and hospitalizations. Yet we present evidence of sustained viral spread among sporadic clusters acting as "hidden reservoirs" during summer 2020. Mathematical modelling shows that increased mobility among residents eventually catalyzed the coalescence of such clusters, thus driving up the number of infections and initiating a new epidemic wave. Our results suggest that the efficacy of public health interventions is, ultimately, limited by the size and structure of epidemic reservoirs, which may warrant prioritization during vaccine deployment.


Subject(s)
COVID-19/transmission , Communicable Disease Control/methods , Genome, Viral/genetics , Mutation , Public Health/methods , SARS-CoV-2/genetics , COVID-19/epidemiology , COVID-19/virology , Geography , Humans , Italy/epidemiology , Pandemics , Phylogeny , Public Health/trends , SARS-CoV-2/classification , SARS-CoV-2/physiology
10.
EClinicalMedicine ; 40: 101101, 2021 Oct.
Article in English | MEDLINE | ID: covidwho-1372973

ABSTRACT

BACKGROUND: Management and control of the COVID-19 pandemic caused by the severe acute respiratory syndrome coronavirus SARS-CoV-2 is critically dependent on quick and reliable identification of the virus in clinical specimens. Detection of viral RNA by a colorimetric reverse transcription loop-mediated isothermal amplification (RT-LAMP) is a simple, reliable and cost-effective assay, deployable in resource-limited settings (RLS). Our objective was to evaluate the intrinsic and extrinsic performances of RT-LAMP in RLS. METHODS: This is a multicenter prospective observational study of diagnostic accuracy, conducted from October 2020 to February 2021 in four African Countries: Cameroon, Ethiopia, Kenya and Nigeria; and in Italy. We enroled 1657 individuals who were either COVID-19 suspect cases, or asymptomatic and presented for screening. RNA extracted from pharyngeal swabs was tested in parallel by a colorimetric RT-LAMP and by a standard real time polymerase chain reaction (RT-PCR). FINDINGS: The sensitivity and specificity of index RT LAMP compared to standard RT-PCR on 1657 prospective specimens from infected individuals was determined. For a subset of 1292 specimens, which underwent exactly the same procedures in different countries, we obtained very high specificity (98%) and positive predictive value (PPV = 99%), while the sensitivity was 87%, with a negative predictive value NPV = 70%, Stratification of RT-PCR data showed superior sensitivity achieved with an RT-PCR cycle threshold (Ct) below 35 (97%), which decreased to 60% above 35. INTERPRETATION: In this field trial, RT-LAMP appears to be a reliable assay, comparable to RT-PCR, particularly with medium-high viral loads (Ct < 35). Hence, RT-LAMP can be deployed in RLS for timely management and prevention of COVID-19, without compromising the quality of output.

11.
Viruses ; 13(5)2021 04 30.
Article in English | MEDLINE | ID: covidwho-1217120

ABSTRACT

Repurposing clinically available drugs to treat the new coronavirus disease 2019 (COVID-19) is an urgent need in the course of the Severe Acute Respiratory Syndrome coronavirus (SARS-CoV-2) pandemic, as very few treatment options are available. The iminosugar Miglustat is a well-characterized drug for the treatment of rare genetic lysosome storage diseases, such as Gaucher and Niemann-Pick type C, and has also been described to be active against a variety of enveloped viruses. The activity of Miglustat is here demonstrated in the micromolar range for SARS-CoV-2 in vitro. The drug acts at the post-entry level and leads to a marked decrease of viral proteins and release of infectious viruses. The mechanism resides in the inhibitory activity toward α-glucosidases that are involved in the early stages of glycoprotein N-linked oligosaccharide processing in the endoplasmic reticulum, leading to a marked decrease of the viral Spike protein. Indeed, the antiviral potential of protein glycosylation inhibitors against SARS-CoV-2 is further highlighted by the low-micromolar activity of the investigational drug Celgosivir. These data point to a relevant role of this approach for the treatment of COVID-19.


Subject(s)
1-Deoxynojirimycin/analogs & derivatives , Antiviral Agents/pharmacology , Drug Repositioning , Glycoside Hydrolase Inhibitors/pharmacology , Indolizines/pharmacology , SARS-CoV-2/drug effects , 1-Deoxynojirimycin/pharmacology , A549 Cells , Animals , COVID-19/drug therapy , Chlorocebus aethiops , Glycosylation/drug effects , HEK293 Cells , Humans , Spike Glycoprotein, Coronavirus/metabolism , Vero Cells , Virus Release/drug effects
12.
Antiviral Res ; 189: 105055, 2021 05.
Article in English | MEDLINE | ID: covidwho-1126674

ABSTRACT

The current emergency of the novel coronavirus SARS-CoV2 urged the need for broad-spectrum antiviral drugs as the first line of treatment. Coronaviruses are a large family of viruses that already challenged humanity in at least two other previous outbreaks and are likely to be a constant threat for the future. In this work we developed a pipeline based on in silico docking of known drugs on SARS-CoV1/2 RNA-dependent RNA polymerase combined with in vitro antiviral assays on both SARS-CoV2 and the common cold human coronavirus HCoV-OC43. Results showed that certain drugs displayed activity for both viruses at a similar inhibitory concentration, while others were specific. In particular, the antipsychotic drug lurasidone and the antiviral drug elbasvir showed promising activity in the low micromolar range against both viruses with good selectivity index.


Subject(s)
Antiviral Agents/pharmacology , Benzofurans/pharmacology , Coronavirus OC43, Human/drug effects , Drug Repositioning , Imidazoles/pharmacology , Lurasidone Hydrochloride/pharmacology , SARS-CoV-2/drug effects , Animals , COVID-19/drug therapy , Cell Line, Tumor , Chlorocebus aethiops , Computer Simulation , Fibroblasts , Humans , Vero Cells , Virus Replication/drug effects
13.
Microbiol Resour Announc ; 10(4)2021 Jan 28.
Article in English | MEDLINE | ID: covidwho-1117311

ABSTRACT

The coding-complete genome sequence of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain isolated from an Iraqi patient was sequenced for the first-time using Illumina MiSeq technology. There was a D614G mutation in the spike protein-coding sequence. This report is valuable for better understanding the spread of the virus in Iraq.

14.
Microbiol Resour Announc ; 10(4)2021 Jan 28.
Article in English | MEDLINE | ID: covidwho-1054614

ABSTRACT

The coding-complete genome sequence of a severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strain isolated from an Iraqi patient was sequenced for the first-time using Illumina MiSeq technology. There was a D614G mutation in the spike protein-coding sequence. This report is valuable for better understanding the spread of the virus in Iraq.

15.
FEBS J ; 287(17): 3606-3608, 2020 09.
Article in English | MEDLINE | ID: covidwho-767428

ABSTRACT

In this COVID-19 Focus Issue, we highlight a collection of recently published The FEBS Journal articles that consider the broader aspects of the COVID-19 pandemic, ranging from the debunking of urban myths to highlighting some of the most pressing questions concerning SARS-CoV-2 infection, treatment, prevention and pathology. The collection comprises two review articles, six Viewpoints, two research papers and one commentary. We hope that these articles will provide readers with an informative and interesting overview that will promote further critical analysis of currently available data and observations on COVID-19.


Subject(s)
COVID-19 , Animals , COVID-19/drug therapy , COVID-19/etiology , COVID-19/prevention & control , COVID-19/therapy , COVID-19 Vaccines/isolation & purification , Disease Reservoirs/virology , Drug Design , Drug Repositioning , Humans , Pandemics , SARS-CoV-2
16.
Open Forum Infect Dis ; 7(10): ofaa421, 2020 Oct.
Article in English | MEDLINE | ID: covidwho-756944

ABSTRACT

BACKGROUND: In hospitalized patients with coronavirus disease 2019 (COVID-19) pneumonia, progression to acute respiratory failure requiring invasive mechanical ventilation (MV) is associated with significant morbidity and mortality. Severe dysregulated systemic inflammation is the putative mechanism. We hypothesize that early prolonged methylprednisolone (MP) treatment could accelerate disease resolution, decreasing the need for intensive care unit (ICU) admission and mortality. METHODS: We conducted a multicenter observational study to explore the association between exposure to prolonged, low-dose MP treatment and need for ICU referral, intubation, or death within 28 days (composite primary end point) in patients with severe COVID-19 pneumonia admitted to Italian respiratory high-dependency units. Secondary outcomes were invasive MV-free days and changes in C-reactive protein (CRP) levels. RESULTS: Findings are reported as MP (n = 83) vs control (n = 90). The composite primary end point was met by 19 vs 40 (adjusted hazard ratio [aHR], 0.41; 95% CI, 0.24-0.72). Transfer to ICU and invasive MV were necessary in 15 vs 27 (P = .07) and 14 vs 26 (P = .10), respectively. By day 28, the MP group had fewer deaths (6 vs 21; aHR, 0.29; 95% CI, 0.12-0.73) and more days off invasive MV (24.0 ±â€…9.0 vs 17.5 ±â€…12.8; P = .001). Study treatment was associated with rapid improvement in PaO2:FiO2 and CRP levels. The complication rate was similar for the 2 groups (P = .84). CONCLUSION: In patients with severe COVID-19 pneumonia, early administration of prolonged MP treatment was associated with a significantly lower hazard of death (71%) and decreased ventilator dependence. Treatment was safe and did not impact viral clearance. A large randomized controlled trial (RECOVERY trial) has been performed that validates these findings. Clinical trial registration. ClinicalTrials.gov NCT04323592.

17.
Redox Biol ; 36: 101682, 2020 09.
Article in English | MEDLINE | ID: covidwho-704017

ABSTRACT

There is an urgent need to identify antivirals against the coronavirus SARS-CoV-2 in the current COVID-19 pandemic and to contain future similar emergencies early on. Specific side-chain cholesterol oxidation products of the oxysterols family have been shown to inhibit a large variety of both enveloped and non-enveloped human viral pathogens. Here we report on the in vitro inhibitory activity of the redox active oxysterol 27-hydroxycholesterol against SARS-CoV-2 and against one of the common cold agents HCoV-OC43 human coronavirus without significant cytotoxicity. Interestingly, physiological serum levels of 27-hydroxycholesterol in SARS-CoV-2 positive subjects were significantly decreased compared to the matched control group, reaching a marked 50% reduction in severe COVID-19 cases. Moreover, no correlation at all was observed between 24-hydroxycholesterol and 25-hydroxycholesterol serum levels and the severity of the disease. Opposite to that of 27-hydroxycholesterol was the behaviour of two recognized markers of redox imbalance, i.e. 7-ketocholesterol and 7ß-hydroxycholesterol, whose serum levels were significantly increased especially in severe COVID-19. The exogenous administration of 27-hydroxycholesterol may represent in the near future a valid antiviral strategy in the worsening of diseases caused by present and emerging coronaviruses.


Subject(s)
Antiviral Agents/pharmacology , Betacoronavirus/drug effects , Coronavirus Infections/blood , Hydroxycholesterols/blood , Pneumonia, Viral/blood , Aged , Animals , Biomarkers/blood , COVID-19 , Chlorocebus aethiops , Coronavirus Infections/pathology , Female , Hep G2 Cells , Humans , Hydroxycholesterols/pharmacology , Male , Middle Aged , Pandemics , Pneumonia, Viral/pathology , SARS-CoV-2 , Vero Cells
18.
J Virol ; 94(15)2020 07 16.
Article in English | MEDLINE | ID: covidwho-690841

ABSTRACT

Currently, there are four seasonal coronaviruses associated with relatively mild respiratory tract disease in humans. However, there is also a plethora of animal coronaviruses which have the potential to cross the species border. This regularly results in the emergence of new viruses in humans. In 2002, severe acute respiratory syndrome coronavirus (SARS-CoV) emerged and rapidly disappeared in May 2003. In 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) was identified as a possible threat to humans, but its pandemic potential so far is minimal, as human-to-human transmission is ineffective. The end of 2019 brought us information about severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emergence, and the virus rapidly spread in 2020, causing an unprecedented pandemic. At present, studies on the virus are carried out using a surrogate system based on the immortalized simian Vero E6 cell line. This model is convenient for diagnostics, but it has serious limitations and does not allow for understanding of the biology and evolution of the virus. Here, we show that fully differentiated human airway epithelium cultures constitute an excellent model to study infection with the novel human coronavirus SARS-CoV-2. We observed efficient replication of the virus in the tissue, with maximal replication at 2 days postinfection. The virus replicated in ciliated cells and was released apically.IMPORTANCE Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged by the end of 2019 and rapidly spread in 2020. At present, it is of utmost importance to understand the biology of the virus, rapidly assess the treatment potential of existing drugs, and develop new active compounds. While some animal models for such studies are under development, most of the research is carried out in Vero E6 cells. Here, we propose fully differentiated human airway epithelium cultures as a model for studies on SARS-CoV-2.


Subject(s)
Betacoronavirus/physiology , Coronavirus Infections/virology , Pneumonia, Viral/virology , Respiratory Mucosa/virology , Severe Acute Respiratory Syndrome/virology , Virus Replication , Animals , COVID-19 , Cell Line , Cells, Cultured , Chlorocebus aethiops , Humans , Pandemics , SARS-CoV-2 , Vero Cells
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