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1.
iScience ; 25(4), 2022.
Article in English | EuropePMC | ID: covidwho-1781054

ABSTRACT

Summary Broadly effective antiviral therapies must be developed to be ready for clinical trials, which should begin soon after the emergence of new life-threatening viruses. Here, we pave the way towards this goal by reviewing conserved druggable virus-host interactions, mechanisms of action, immunomodulatory properties of available broad-spectrum antivirals (BSAs), routes of BSA delivery, and interactions of BSAs with other antivirals. Based on the review, we concluded that the range of indications of BSAs can be expanded, and new pan- and cross-viral mono- and combinational therapies can be developed. We have also developed a new scoring algorithm that can help identify the most promising few of the thousands of potential BSAs and BSA-containing drug cocktails (BCCs) to prioritize their development during the critical period between the identification of a new virus and the development of virus-specific vaccines, drugs, and therapeutic antibodies. Graphical Pharmaceutical preparation;Pharmaceutical science;Pharmacology;Chemistry

2.
EuropePMC; 2022.
Preprint in English | EuropePMC | ID: ppcovidwho-329037

ABSTRACT

Nanomaterials have been proposed as good candidates for the elimination of viruses due to their multimodal mechanisms of action. Here, we tested the antiviral potential of cerium dioxide (CeO 2 ) nanoparticles which is largely unexplored.Two types of nano-CeO 2 particles with opposing surface charge, nano-CeO 2 (+) and nano-CeO 2 (-), were assessed for their capability to decrease the plaque forming units (PFU) of four enveloped and two non-enveloped viruses during 1 h exposure. Statistically significant antiviral activity of nano-CeO 2 towards enveloped coronavirus SARS-CoV-2 and influenza virus A/WSN/1933 was registered already at 20 mg Ce/l. Significant decrease in PFU of other two enveloped viruses, transmissible gastroenteritis virus TGEV and bacteriophage φ6 was evidenced at 200 mg Ce/l. For all the enveloped viruses the maximum reduction of PFU after 1 h exposure to nano-CeO 2 exceeded 2 logs, that has been considered as the lowest biologically meaningful activity in antiviral applications. For most of the enveloped viruses, 1 h exposure to nano-CeO 2 resulted in ≥ 4 log reduction in PFU. As expected, the sensitivity of non-enveloped viruses towards nano-CeO 2 was significantly lower than that of enveloped viruses. Until the highest tested concentration, 2000 mg Ce/l neither of the nano-CeO 2 showed an effect on picornavirus EMCV and only nano-CeO 2 (-) caused a slight non-monotonic response in MS2 bacteriophage.Parallel testing of antiviral activity of Ce 3+ ions and SiO 2 nanoparticles allows to conclude that nano-CeO 2 activity was due to neither released Ce 3+ ions nor nonspecific effects of any nanosized particulate. Interestingly, we did not evidence any significant antiviral activity of Ag nanoparticles at 1 h exposure. This result referred to notably higher antiviral activity of nano-CeO 2 compared with nanosilver that has been generally considered as active against viruses. Although exhibiting antiviral effects, the antibacterial activity of nano-CeO 2 was very low. These results along with non-existent cytotoxicity nano-CeO 2 allow us to propose nano-CeO 2 for specific antiviral applications.

3.
Viruses ; 13(12)2021 12 11.
Article in English | MEDLINE | ID: covidwho-1572663

ABSTRACT

BACKGROUND: There is an urgent need for new antivirals with powerful therapeutic potential and tolerable side effects. METHODS: Here, we tested the antiviral properties of interferons (IFNs), alone and with other drugs in vitro. RESULTS: While IFNs alone were insufficient to completely abolish replication of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), IFNα, in combination with remdesivir, EIDD-2801, camostat, cycloheximide, or convalescent serum, proved to be more effective. Transcriptome and metabolomic analyses revealed that the IFNα-remdesivir combination suppressed SARS-CoV-2-mediated changes in Calu-3 cells and lung organoids, although it altered the homeostasis of uninfected cells and organoids. We also demonstrated that IFNα combinations with sofosbuvir, telaprevir, NITD008, ribavirin, pimodivir, or lamivudine were effective against HCV, HEV, FLuAV, or HIV at lower concentrations, compared to monotherapies. CONCLUSIONS: Altogether, our results indicated that IFNα can be combined with drugs that affect viral RNA transcription, protein synthesis, and processing to make synergistic combinations that can be attractive targets for further pre-clinical and clinical development against emerging and re-emerging viral infections.


Subject(s)
Antiviral Agents/pharmacology , Interferon-alpha/pharmacology , SARS-CoV-2/drug effects , Cell Line , Drug Synergism , Humans , Lung/drug effects , Lung/metabolism , Lung/virology , Metabolome/drug effects , Organoids , RNA, Viral/biosynthesis , RNA, Viral/drug effects , Signal Transduction/drug effects , Transcriptome/drug effects , Virus Replication/drug effects , Viruses/classification , Viruses/drug effects
4.
2021.
Preprint in English | Other preprints | ID: ppcovidwho-294998

ABSTRACT

SARS-CoV-2 and its vaccine/immune-escaping variants continue to pose a serious threat to public health due to a paucity of effective, rapidly deployable, and widely available treatments. Here, we address these challenges by combining Pegasys (IFNa) and nafamostat to effectively suppress SARS-CoV-2 infection in cell culture and hamsters. Our results indicate that Serpin E1 is an important mediator of the antiviral activity of IFNa and that both Serpin E1 and camostat can target the same cellular factor TMPRSS2, which plays a critical role in viral replication. The low doses of the drugs in combination may have several clinical advantages, including fewer adverse events and improved patient outcome. Thus, our study may provide a proactive solution for the ongoing pandemic and potential future coronavirus outbreaks, which is still urgently required in many parts of the world.

5.
Viruses ; 13(9)2021 09 04.
Article in English | MEDLINE | ID: covidwho-1478110

ABSTRACT

SARS-CoV-2 and its vaccine/immune-escaping variants continue to pose a serious threat to public health due to a paucity of effective, rapidly deployable, and widely available treatments. Here, we address these challenges by combining Pegasys (IFNα) and nafamostat to effectively suppress SARS-CoV-2 infection in cell culture and hamsters. Our results indicate that Serpin E1 is an important mediator of the antiviral activity of IFNα and that both Serpin E1 and nafamostat can target the same cellular factor TMPRSS2, which plays a critical role in viral replication. The low doses of the drugs in combination may have several clinical advantages, including fewer adverse events and improved patient outcome. Thus, our study may provide a proactive solution for the ongoing pandemic and potential future coronavirus outbreaks, which is still urgently required in many parts of the world.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Benzamidines/pharmacology , COVID-19/metabolism , COVID-19/virology , Guanidines/pharmacology , Interferon-alpha/pharmacology , SARS-CoV-2/drug effects , Serine Endopeptidases/metabolism , Animals , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Benzamidines/therapeutic use , COVID-19/drug therapy , Cricetinae , Disease Models, Animal , Drug Therapy, Combination , Female , Guanidines/therapeutic use , Host-Pathogen Interactions/drug effects , Humans , Interferon-alpha/therapeutic use , Virus Replication/drug effects
6.
Front Immunol ; 12: 709759, 2021.
Article in English | MEDLINE | ID: covidwho-1450807

ABSTRACT

The clinical features of SARS-CoV-2 infection range from asymptomatic to severe disease with life-threatening complications. Understanding the persistence of immune responses in asymptomatic individuals merit special attention because of their importance in controlling the spread of the infections. We here studied the antibody and T cell responses, and a wide range of inflammation markers, in 56 SARS-CoV-2 antibody-positive individuals, identified by a population screen after the first wave of SARS-CoV-2 infection. These, mostly asymptomatic individuals, were reanalyzed 7-8 months after their infection together with 115 age-matched seronegative controls. We found that 7-8 months after the infection their antibodies to SARS-CoV-2 Nucleocapsid (N) protein declined whereas we found no decrease in the antibodies to Spike receptor-binding domain (S-RBD) when compared to the findings at seropositivity identification. In contrast to antibodies to N protein, the antibodies to S-RBD correlated with the viral neutralization capacity and with CD4+ T cell responses as measured by antigen-specific upregulation of CD137 and CD69 markers. Unexpectedly we found the asymptomatic antibody-positive individuals to have increased serum levels of S100A12, TGF-alpha, IL18, and OSM, the markers of activated macrophages-monocytes, suggesting long-term persistent inflammatory effect associated with the viral infection in asymptomatic individuals. Our results support the evidence for the long-term persistence of the inflammation process and the need for post-infection clinical monitoring of SARS-CoV-2 infected asymptomatic individuals.


Subject(s)
Antibodies, Viral/blood , Asymptomatic Infections , CD4-Positive T-Lymphocytes/immunology , COVID-19/pathology , Inflammation Mediators/blood , SARS-CoV-2/immunology , Antibodies, Neutralizing/immunology , Antibodies, Viral/immunology , CD4 Lymphocyte Count , Coronavirus Nucleocapsid Proteins/immunology , Humans , Inflammation/immunology , Interleukin-18/blood , Macrophages/immunology , Monocytes/immunology , Oncostatin M/blood , Phosphoproteins/immunology , Protein Domains/immunology , S100A12 Protein/blood , Spike Glycoprotein, Coronavirus/immunology , Transforming Growth Factor alpha/blood
7.
Viruses ; 13(9)2021 09 04.
Article in English | MEDLINE | ID: covidwho-1390793

ABSTRACT

SARS-CoV-2 and its vaccine/immune-escaping variants continue to pose a serious threat to public health due to a paucity of effective, rapidly deployable, and widely available treatments. Here, we address these challenges by combining Pegasys (IFNα) and nafamostat to effectively suppress SARS-CoV-2 infection in cell culture and hamsters. Our results indicate that Serpin E1 is an important mediator of the antiviral activity of IFNα and that both Serpin E1 and nafamostat can target the same cellular factor TMPRSS2, which plays a critical role in viral replication. The low doses of the drugs in combination may have several clinical advantages, including fewer adverse events and improved patient outcome. Thus, our study may provide a proactive solution for the ongoing pandemic and potential future coronavirus outbreaks, which is still urgently required in many parts of the world.


Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Benzamidines/pharmacology , COVID-19/metabolism , COVID-19/virology , Guanidines/pharmacology , Interferon-alpha/pharmacology , SARS-CoV-2/drug effects , Serine Endopeptidases/metabolism , Animals , Anti-Inflammatory Agents, Non-Steroidal/therapeutic use , Benzamidines/therapeutic use , COVID-19/drug therapy , Cricetinae , Disease Models, Animal , Drug Therapy, Combination , Female , Guanidines/therapeutic use , Host-Pathogen Interactions/drug effects , Humans , Interferon-alpha/therapeutic use , Virus Replication/drug effects
8.
Vaccine ; 39(38): 5376-5384, 2021 09 07.
Article in English | MEDLINE | ID: covidwho-1340875

ABSTRACT

PURPOSE: In Estonia, during the first wave of COVID-19 total number of cases confirmed by PCR was 13.3/10,000, similar in most regions, including capital Tallinn, but in the hotspot of Estonian epidemic, an island Saaremaa, the cumulative incidence was 166.1/10,000. We aimed to determine the prevalence of SARS-CoV-2 IgG antibodies in these two regions, symptoms associated with infection and factors associated with antibody concentrations. METHODS: Participants were selected using stratified (formed by age decades) random sampling and recruited by general practitioners. IgG or neutralizing antibodies were determined from sera by four assays. Symptoms associated with seropositivity were analyzed by multiple correspondence analysis, antibody concentrations by multiple linear regression. RESULTS: Total of 3608 individual were invited and 1960 recruited from May 8 to July 31, 2020. Seroprevalence was 1.5% (95% confidence interval (CI) 0.9-2.5) and 6.3% (95% CI 5.0-7.9), infection fatality rate 0.1% (95% CI 0.0-0.2) and 1.3% (95% CI 0.4-2.1) in Tallinn and Saaremaa, respectively. Of seropositive subjects 19.2% (14/73) had acute respiratory illness. Fever, diarrhea and the absence of cough and runny nose were associated with seropositivity in individuals aged 50 or more years. IgG, but not neutralizing antibodies concentrations were higher if fever, difficulty breathing, shortness of breath, chest pain or diarrhea was present, or hospitalization required. CONCLUSION: Similarly to other European countries the seroprevalence of SARS-CoV-2 in Estonia was low even in the hotspot region Saaremaa suggesting that majority of population is susceptible to SARS-CoV-2. Focusing only on respiratory symptoms may delay accurate diagnosis of SARS-CoV-2 infection.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Viral , Estonia/epidemiology , Humans , Immunoglobulin G , Prevalence , Seroepidemiologic Studies
9.
Euro Surveill ; 26(27)2021 07.
Article in English | MEDLINE | ID: covidwho-1304570

ABSTRACT

We compared the performance of SARS-CoV-2 neutralising antibody testing between 12 European laboratories involved in convalescent plasma trials. Raw titres differed almost 100-fold differences between laboratories when blind-testing 15 plasma samples. Calibration of titres in relation to the reference reagent and standard curve obtained by testing a dilution series reduced the inter-laboratory variability ca 10-fold. The harmonisation of neutralising antibody quantification is a vital step towards determining the protective and therapeutic levels of neutralising antibodies.


Subject(s)
COVID-19 , SARS-CoV-2 , Antibodies, Neutralizing , Antibodies, Viral , COVID-19/therapy , Europe , Humans , Immunization, Passive
10.
JHEP Rep ; 3(4): 100296, 2021 Aug.
Article in English | MEDLINE | ID: covidwho-1293968

ABSTRACT

BACKGROUND & AIMS: Chronic hepatitis B is an incurable disease. Addressing the unmet medical need for therapies has been hampered by a lack of suitable cell culture models to investigate the HBV life cycle in a single experimental setup. We sought to develop a platform suitable to investigate all aspects of the entire HBV life cycle. METHODS: HepG2-NTCPsec+ cells were inoculated with HBV. Supernatants of infected cells were transferred to naïve cells. Inhibition of infection was determined in primary and secondary infected cells by high-content imaging of viral and cellular factors. Novel antivirals were triaged in cells infected with cell culture- or patient-derived HBV and in stably virus replicating cells. HBV internalisation and target-based receptor binding assays were conducted. RESULTS: We developed an HBV platform, screened 2,102 drugs and bioactives, and identified 3 early and 38 late novel HBV life cycle inhibitors using infectious HBV genotype D. Two early inhibitors, pranlukast (EC50 4.3 µM; 50% cytotoxic concentration [CC50] >50 µM) and cytochalasin D (EC50 0.07 µM; CC50 >50 µM), and 2 late inhibitors, fludarabine (EC50 0.1 µM; CC50 13.4 µM) and dexmedetomidine (EC50 6.2 µM; CC50 >50 µM), were further investigated. Pranlukast inhibited HBV preS1 binding, whereas cytochalasin D prevented the internalisation of HBV. Fludarabine inhibited the secretion of HBV progeny DNA, whereas dexmedetomidine interfered with the infectivity of HBV progeny. Patient-derived HBV genotype C was efficiently inhibited by fludarabine (EC50 0.08 µM) and dexmedetomidine (EC50 8.7 µM). CONCLUSIONS: The newly developed high-content assay is suitable to screen large-scale drug libraries, enables monitoring of the entire HBV life cycle, and discriminates between inhibition of early and late viral life cycle events. LAY SUMMARY: HBV infection is an incurable, chronic disease with few available treatments. Addressing this unmet medical need has been hampered by a lack of suitable cell culture models to study the entire viral life cycle in a single experimental setup. We developed an image-based approach suitable to screen large numbers of drugs, using a cell line that can be infected by HBV and produces large amounts of virus particles. By transferring viral supernatants from these infected cells to uninfected target cells, we could monitor the entire viral life cycle. We used this system to screen drug libraries and identified novel anti-HBV inhibitors that potently inhibit HBV in various phases of its life cycle. This assay will be an important new tool to study the HBV life cycle and accelerate the development of novel therapeutic strategies.

11.
Viruses ; 12(10):1178, 2020.
Article in English | MDPI | ID: covidwho-875311

ABSTRACT

Combination therapies have become a standard for the treatment for HIV and hepatitis C virus (HCV) infections. They are advantageous over monotherapies due to better efficacy, reduced toxicity, as well as the ability to prevent the development of resistant viral strains and to treat viral co-infections. Here, we identify new synergistic combinations against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), echovirus 1 (EV1), hepatitis C virus (HCV) and human immunodeficiency virus 1 (HIV-1) in vitro. We observed synergistic activity of nelfinavir with convalescent serum and with purified neutralizing antibody 23G7 against SARS-CoV-2 in human lung epithelial Calu-3 cells. We also demonstrated synergistic activity of nelfinavir with EIDD-2801 or remdesivir in Calu-3 cells. In addition, we showed synergistic activity of vemurafenib with emetine, homoharringtonine, anisomycin, or cycloheximide against EV1 infection in human lung epithelial A549 cells. We also found that combinations of sofosbuvir with brequinar or niclosamide are synergistic against HCV infection in hepatocyte-derived Huh-7.5 cells, and that combinations of monensin with lamivudine or tenofovir are synergistic against HIV-1 infection in human cervical TZM-bl cells. These results indicate that synergy is achieved when a virus-directed antiviral is combined with another virus- or host-directed agent. Finally, we present an online resource that summarizes novel and known antiviral drug combinations and their developmental status.

12.
Viruses ; 12(6)2020 06 13.
Article in English | MEDLINE | ID: covidwho-602214

ABSTRACT

As of June 2020, the number of people infected with severe acute respiratory coronavirus 2 (SARS-CoV-2) continues to skyrocket, with more than 6.7 million cases worldwide. Both the World Health Organization (WHO) and United Nations (UN) has highlighted the need for better control of SARS-CoV-2 infections. However, developing novel virus-specific vaccines, monoclonal antibodies and antiviral drugs against SARS-CoV-2 can be time-consuming and costly. Convalescent sera and safe-in-man broad-spectrum antivirals (BSAAs) are readily available treatment options. Here, we developed a neutralization assay using SARS-CoV-2 strain and Vero-E6 cells. We identified the most potent sera from recovered patients for the treatment of SARS-CoV-2-infected patients. We also screened 136 safe-in-man broad-spectrum antivirals against the SARS-CoV-2 infection in Vero-E6 cells and identified nelfinavir, salinomycin, amodiaquine, obatoclax, emetine and homoharringtonine. We found that a combination of orally available virus-directed nelfinavir and host-directed amodiaquine exhibited the highest synergy. Finally, we developed a website to disseminate the knowledge on available and emerging treatments of COVID-19.


Subject(s)
Antiviral Agents/pharmacology , Betacoronavirus/drug effects , Coronavirus Infections/drug therapy , Neutralization Tests/methods , Pneumonia, Viral/drug therapy , Amodiaquine/pharmacology , Animals , COVID-19 , Caco-2 Cells , Cell Line, Tumor , Chlorocebus aethiops , Coronavirus Infections/therapy , Drug Therapy, Combination , Emetine/pharmacology , HEK293 Cells , HT29 Cells , Homoharringtonine/pharmacology , Humans , Immune Sera/immunology , Immunization, Passive/methods , Indoles , Nelfinavir/pharmacology , Pandemics , Pyrans/pharmacology , Pyrroles/pharmacology , SARS-CoV-2 , Vero Cells
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