RESUMO
Seasonal and pandemic-associated influenza strains cause highly contagious viral respiratory infections that can lead to severe illness and excess mortality. Here, we report on the optimization of our small-molecule inhibitor F0045(S) targeting the influenza hemagglutinin (HA) stem with our Sulfur-Fluoride Exchange (SuFEx) click chemistry-based high-throughput medicinal chemistry (HTMC) strategy. A combination of SuFEx- and amide-based lead molecule diversification and structure-guided design led to identification and validation of ultrapotent influenza fusion inhibitors with subnanomolar EC50 cellular antiviral activity against several influenza A group 1 strains. X-ray structures of six of these compounds with HA indicate that the appended moieties occupy additional pockets on the HA surface and increase the binding interaction, where the accumulation of several polar interactions also contributes to the improved affinity. The compounds here represent the most potent HA small-molecule inhibitors to date. Our divergent HTMC platform is therefore a powerful, rapid, and cost-effective approach to develop bioactive chemical probes and drug-like candidates against viral targets.
Assuntos
Antivirais , Glicoproteínas de Hemaglutininação de Vírus da Influenza , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Glicoproteínas de Hemaglutininação de Vírus da Influenza/química , Humanos , Antivirais/farmacologia , Antivirais/química , Química Farmacêutica/métodos , Ensaios de Triagem em Larga Escala/métodos , Influenza Humana/tratamento farmacológico , Influenza Humana/virologia , Cristalografia por Raios X/métodos , Química Click/métodos , Animais , Vírus da Influenza A/efeitos dos fármacos , Células Madin Darby de Rim Canino , Inibidores de Proteínas Virais de Fusão/farmacologia , Inibidores de Proteínas Virais de Fusão/química , CãesRESUMO
Clofazimine and Arbidol have both been reported to be effective in vitro SARS-CoV-2 fusion inhibitors. Both are promising drugs that have been repurposed for the treatment of COVID-19 and have been used in several previous and ongoing clinical trials. Small-molecule bindings to expressed constructs of the trimeric S2 segment of Spike and the full-length SARS-CoV-2 Spike protein were measured using a Surface Plasmon Resonance (SPR) binding assay. We demonstrate that Clofazimine, Toremifene, Arbidol and its derivatives bind to the S2 segment of the Spike protein. Clofazimine provided the most reliable and highest-quality SPR data for binding with S2 over the conditions explored. A molecular docking approach was used to identify the most favorable binding sites on the S2 segment in the prefusion conformation, highlighting two possible small-molecule binding sites for fusion inhibitors. Results related to molecular docking and modeling of the structure-activity relationship (SAR) of a newly reported series of Clofazimine derivatives support the proposed Clofazimine binding site on the S2 segment. When the proposed Clofazimine binding site is superimposed with other experimentally determined coronavirus structures in structure-sequence alignments, the changes in sequence and structure may rationalize the broad-spectrum antiviral activity of Clofazimine in closely related coronaviruses such as SARS-CoV, MERS, hCoV-229E, and hCoV-OC43.
Assuntos
Clofazimina , Ligação Proteica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus , Humanos , Antivirais/farmacologia , Antivirais/química , Sítios de Ligação , Clofazimina/farmacologia , Clofazimina/química , Clofazimina/metabolismo , Tratamento Farmacológico da COVID-19 , Indóis , Simulação de Acoplamento Molecular , SARS-CoV-2/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/metabolismo , Glicoproteína da Espícula de Coronavírus/química , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Relação Estrutura-Atividade , Sulfetos , Ressonância de Plasmônio de Superfície , Inibidores de Proteínas Virais de Fusão/farmacologia , Inibidores de Proteínas Virais de Fusão/químicaRESUMO
Filoviruses enter cells through macropinocytosis and trafficking into the endosomes in which they bind to the receptor Niemann-Pick C1 protein (NPC1) for membrane fusion and entry into the cytoplasm. The endosomal receptor-binding is critical step for filovirus entry. Designing inhibitors to block receptor binding will prevent viral entry. Using available binding structural information from the co-crystal structures of the viral GP with the receptor NPC1 or with monoclonal antibodies, we have conducted structure-based design of peptide inhibitors to target the receptor binding site (RBS). The designed peptides were tested for their inhibition activity against pseudo-typed or replication-competent viruses in a cell-based assay. The results indicate that these peptides exhibited strong activities against both Ebola and Marburg virus infection. It is expected that these peptides can be further developed for therapeutic use to treat filovirus infection and combat the outbreaks.
Assuntos
Filoviridae , Receptores Virais , Inibidores de Proteínas Virais de Fusão , Sítios de Ligação , Proteínas de Transporte/metabolismo , Linhagem Celular , Ebolavirus/fisiologia , Endossomos/metabolismo , Filoviridae/química , Filoviridae/efeitos dos fármacos , Doença pelo Vírus Ebola , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Ligantes , Glicoproteínas de Membrana/metabolismo , Proteína C1 de Niemann-Pick/metabolismo , Receptores Virais/química , Receptores Virais/metabolismo , Inibidores de Proteínas Virais de Fusão/química , Inibidores de Proteínas Virais de Fusão/farmacologia , Internalização do Vírus/efeitos dos fármacosRESUMO
The coronavirus disease 2019 (COVID-19) pandemic caused by infection of SARS-CoV-2 and its variants has posed serious threats to global public health, thus calling for the development of potent and broad-spectrum antivirals. We previously designed and developed a peptide-based pan-coronavirus (CoV) fusion inhibitor, EK1, which is effective against all human CoVs (HCoV) tested by targeting the HCoV S protein HR1 domain. However, its relatively short half-life may limit its clinical use. Therefore, we designed, constructed, and expressed a recombinant protein, FL-EK1, which consists of a modified fibronectin type III domain (FN3) with albumin-binding capacity, a flexible linker, and EK1. As with EK1, we found that FL-EK1 could also effectively inhibit infection of SARS-CoV-2 and its variants, as well as HCoV-OC43. Furthermore, it protected mice from infection by the SARS-CoV-2 Delta variant and HCoV-OC43. Importantly, the half-life of FL-EK1 (30 h) is about 15.7-fold longer than that of EK1 (1.8 h). These results suggest that FL-EK1 is a promising candidate for the development of a pan-CoV fusion inhibitor-based long-acting antiviral drug for preventing and treating infection by current and future SARS-CoV-2 variants, as well as other HCoVs.
Assuntos
Tratamento Farmacológico da COVID-19 , SARS-CoV-2 , Inibidores de Proteínas Virais de Fusão , Animais , Antivirais/química , Antivirais/farmacologia , Antivirais/uso terapêutico , Infecções por Coronavirus/tratamento farmacológico , Domínio de Fibronectina Tipo III , Meia-Vida , Camundongos , Proteínas Recombinantes de Fusão , SARS-CoV-2/genética , Glicoproteína da Espícula de Coronavírus/metabolismo , Inibidores de Proteínas Virais de Fusão/química , Inibidores de Proteínas Virais de Fusão/farmacologiaRESUMO
A key step in infections by enveloped viruses, such as influenza, is the fusion between the viral envelope and the host cell membrane, which allows the virus to insert its genetic material into the host cell and replicate. The influenza virus fusion process is promoted by hemagglutinin (HA), a glycoprotein that contains three identical monomers composed of two polypeptide chains (HA1 and HA2). Early studies on this protein revealed that HA-mediated fusion involves the insertion of the HA2 N-terminal segment into the host membrane and that this segment, known as the fusion peptide, is a key player in the fusion process. This mini-review highlights the main findings that have been obtained by experimental and computational studies on the HA fusion peptide, which give us a glimpse of its mode of action.
Assuntos
Vírus da Influenza A/patogenicidade , Influenza Humana/imunologia , Proteínas Virais de Fusão/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Membranas , Modelos Moleculares , Peptídeos , Conformação Proteica , Inibidores de Proteínas Virais de Fusão/farmacologia , Proteínas Virais de Fusão/genéticaRESUMO
Lassa virus (LASV)-a member of the family Arenaviridae-causes Lassa fever in humans and is endemic in West Africa. Currently, no approved drugs are available. We screened 2480 small compounds for their potential antiviral activity using pseudotyped vesicular stomatitis virus harboring the LASV glycoprotein (VSV-LASVGP) and a related prototypic arenavirus, lymphocytic choriomeningitis virus (LCMV). Follow-up studies confirmed that CP100356 hydrochloride (CP100356), a specific P-glycoprotein (P-gp) inhibitor, suppressed VSV-LASVGP, LCMV, and LASV infection with half maximal inhibitory concentrations of 0.52, 0.54, and 0.062 µM, respectively, without significant cytotoxicity. Although CP100356 did not block receptor binding at the cell surface, it inhibited low-pH-dependent membrane fusion mediated by arenavirus glycoproteins. P-gp downregulation did not cause a significant reduction in either VSV-LASVGP or LCMV infection, suggesting that P-gp itself is unlikely to be involved in arenavirus entry. Finally, our data also indicate that CP100356 inhibits the infection by other mammarenaviruses. Thus, our findings suggest that CP100356 can be considered as an effective virus entry inhibitor for LASV and other highly pathogenic mammarenaviruses.
Assuntos
Membro 1 da Subfamília B de Cassetes de Ligação de ATP/efeitos dos fármacos , Arenaviridae/metabolismo , Isoquinolinas/farmacologia , Vírus Lassa/efeitos dos fármacos , Quinazolinas/farmacologia , Internalização do Vírus/efeitos dos fármacos , Animais , Antivirais/farmacologia , Chlorocebus aethiops , Humanos , Febre Lassa/tratamento farmacológico , Febre Lassa/virologia , Vírus da Coriomeningite Linfocítica , Receptores Virais , Células Vero , Estomatite Vesicular/virologia , Inibidores de Proteínas Virais de Fusão/farmacologiaRESUMO
Respiratory syncytial virus (RSV) is a major pathogen that causes severe lower respiratory tract infection in infants, the elderly and the immunocompromised worldwide. At present no approved specific drugs or vaccines are available to treat this pathogen. Recently, several promising candidates targeting RSV entry and multiplication steps are under investigation. However, it is possible to lead to drug resistance under the long-term treatment. Therapeutic combinations constitute an alternative to prevent resistance and reduce antiviral doses. Therefore, we tested in vitro two-drug combinations of fusion inhibitors (GS5806, Ziresovir and BMS433771) and RNA-dependent RNA polymerase complex (RdRp) inhibitors (ALS8176, RSV604, and Cyclopamine). The statistical program MacSynergy II was employed to determine synergism, additivity or antagonism between drugs. From the result, we found that combinations of ALS8176 and Ziresovir or GS5806 exhibit additive effects against RSV in vitro, with interaction volume of 50 µM2% and 31 µM2% at 95% confidence interval, respectively. On the other hand, all combinations between fusion inhibitors showed antagonistic effects against RSV in vitro, with volume of antagonism ranging from -50 µM2 % to -176 µM2 % at 95% confidence interval. Over all, our results suggest the potentially therapeutic combinations in combating RSV in vitro could be considered for further animal and clinical evaluations.
Assuntos
Antivirais/farmacologia , Descoberta de Drogas , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Antivirais/química , Antivirais/uso terapêutico , Descoberta de Drogas/métodos , Sinergismo Farmacológico , Quimioterapia Combinada , Humanos , Quinazolinas/química , Quinazolinas/farmacologia , Quinazolinas/uso terapêutico , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Infecções por Vírus Respiratório Sincicial/virologia , Bibliotecas de Moléculas Pequenas , Sulfonas , Tiazepinas/química , Tiazepinas/farmacologia , Tiazepinas/uso terapêutico , Inibidores de Proteínas Virais de Fusão/química , Inibidores de Proteínas Virais de Fusão/farmacologia , Inibidores de Proteínas Virais de Fusão/uso terapêuticoRESUMO
Containment of the COVID-19 pandemic requires reducing viral transmission. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is initiated by membrane fusion between the viral and host cell membranes, which is mediated by the viral spike protein. We have designed lipopeptide fusion inhibitors that block this critical first step of infection and, on the basis of in vitro efficacy and in vivo biodistribution, selected a dimeric form for evaluation in an animal model. Daily intranasal administration to ferrets completely prevented SARS-CoV-2 direct-contact transmission during 24-hour cohousing with infected animals, under stringent conditions that resulted in infection of 100% of untreated animals. These lipopeptides are highly stable and thus may readily translate into safe and effective intranasal prophylaxis to reduce transmission of SARS-CoV-2.
Assuntos
COVID-19/transmissão , Lipopeptídeos/administração & dosagem , Fusão de Membrana/efeitos dos fármacos , SARS-CoV-2/efeitos dos fármacos , Inibidores de Proteínas Virais de Fusão/administração & dosagem , Internalização do Vírus/efeitos dos fármacos , Administração Intranasal , Animais , COVID-19/prevenção & controle , COVID-19/virologia , Chlorocebus aethiops , Modelos Animais de Doenças , Desenho de Fármacos , Furões , Lipopeptídeos/química , Lipopeptídeos/farmacocinética , Lipopeptídeos/farmacologia , Camundongos , Profilaxia Pré-Exposição , SARS-CoV-2/isolamento & purificação , SARS-CoV-2/fisiologia , Glicoproteína da Espícula de Coronavírus/metabolismo , Distribuição Tecidual , Células Vero , Inibidores de Proteínas Virais de Fusão/química , Inibidores de Proteínas Virais de Fusão/farmacocinética , Inibidores de Proteínas Virais de Fusão/farmacologiaAssuntos
Infecções por Coronavirus/tratamento farmacológico , Coronavirus/efeitos dos fármacos , Desenho de Fármacos , Glicoproteína da Espícula de Coronavírus , Inibidores de Proteínas Virais de Fusão/farmacologia , Proteínas Virais de Fusão/metabolismo , Sequência de Aminoácidos , Humanos , Estrutura Secundária de Proteína , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/metabolismoRESUMO
Although enveloped viruses canonically mediate particle entry through virus-cell fusion, certain viruses can spread by cell-cell fusion, brought about by receptor engagement and triggering of membrane-bound, viral-encoded fusion proteins on the surface of cells. The formation of pathogenic syncytia or multinucleated cells is seen in vivo, but their contribution to viral pathogenesis is poorly understood. For the negative-strand paramyxoviruses respiratory syncytial virus (RSV) and Nipah virus (NiV), cell-cell spread is highly efficient because their oligomeric fusion protein complexes are active at neutral pH. The recently emerged severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has also been reported to induce syncytia formation in infected cells, with the spike protein initiating cell-cell fusion. Whilst it is well established that fusion protein-specific antibodies can block particle attachment and/or entry into the cell (canonical virus neutralization), their capacity to inhibit cell-cell fusion and the consequences of this neutralization for the control of infection are not well characterized, in part because of the lack of specific tools to assay and quantify this activity. Using an adapted bimolecular fluorescence complementation assay, based on a split GFP-Renilla luciferase reporter, we have established a micro-fusion inhibition test (mFIT) that allows the identification and quantification of these neutralizing antibodies. This assay has been optimized for high-throughput use and its applicability has been demonstrated by screening monoclonal antibody (mAb)-mediated inhibition of RSV and NiV fusion and, separately, the development of fusion-inhibitory antibodies following NiV vaccine immunization in pigs. In light of the recent emergence of coronavirus disease 2019 (COVID-19), a similar assay was developed for SARS-CoV-2 and used to screen mAbs and convalescent patient plasma for fusion-inhibitory antibodies. Using mFITs to assess antibody responses following natural infection or vaccination is favourable, as this assay can be performed entirely at low biocontainment, without the need for live virus. In addition, the repertoire of antibodies that inhibit cell-cell fusion may be different to those that inhibit particle entry, shedding light on the mechanisms underpinning antibody-mediated neutralization of viral spread.
Assuntos
Anticorpos Neutralizantes/farmacologia , Anticorpos Antivirais/farmacologia , COVID-19/diagnóstico , Infecções por Henipavirus/diagnóstico , Ensaios de Triagem em Larga Escala , Infecções por Vírus Respiratório Sincicial/diagnóstico , Proteínas Virais de Fusão/antagonistas & inibidores , Animais , Anticorpos Neutralizantes/isolamento & purificação , Anticorpos Neutralizantes/metabolismo , Anticorpos Antivirais/isolamento & purificação , Anticorpos Antivirais/metabolismo , COVID-19/imunologia , COVID-19/virologia , Fusão Celular , Convalescença , Genes Reporter , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Células HEK293 , Infecções por Henipavirus/imunologia , Infecções por Henipavirus/virologia , Humanos , Soros Imunes/química , Luciferases/genética , Luciferases/metabolismo , Modelos Moleculares , Vírus Nipah/imunologia , Vírus Nipah/patogenicidade , Conformação Proteica , Infecções por Vírus Respiratório Sincicial/imunologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sincicial Respiratório Humano/imunologia , Vírus Sincicial Respiratório Humano/patogenicidade , SARS-CoV-2/imunologia , SARS-CoV-2/patogenicidade , Suínos , Inibidores de Proteínas Virais de Fusão/química , Inibidores de Proteínas Virais de Fusão/metabolismo , Inibidores de Proteínas Virais de Fusão/farmacologia , Proteínas Virais de Fusão/genética , Proteínas Virais de Fusão/imunologiaRESUMO
Inhibitors of the respiratory syncytial virus (RSV) fusion protein block entry of the virus into the cell and have shown varying efficacy in a human challenge model of RSV disease. Trials in patient populations are yet to show significant benefits. Jonckers et al. ( J. Med. Chem. 2020, DOI: 10.1021/acs.jmedchem.0c00226) describe the discovery of JNJ-53718678 which can now claim the leading position in clinical evaluation. For RSV inhibitors, the current status of the clinical development of the compound is discussed.
Assuntos
Antivirais/química , Imidazolidinas/química , Indóis/química , Vírus Sincicial Respiratório Humano/efeitos dos fármacos , Inibidores de Proteínas Virais de Fusão/química , Antivirais/farmacologia , Antivirais/uso terapêutico , Cristalografia por Raios X/métodos , Humanos , Imidazolidinas/farmacologia , Imidazolidinas/uso terapêutico , Indóis/farmacologia , Indóis/uso terapêutico , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Vírus Sincicial Respiratório Humano/fisiologia , Resultado do Tratamento , Inibidores de Proteínas Virais de Fusão/farmacologiaRESUMO
In the past 17 years, three novel coronaviruses have caused severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and the coronavirus disease 2019 (COVID-19). As emerging infectious diseases, they were characterized by their novel pathogens and transmissibility without available clinical drugs or vaccines. This is especially true for the newly identified COVID-19 caused by SARS coronavirus 2 (SARS-CoV-2) for which, to date, no specific antiviral drugs or vaccines have been approved. Similar to SARS and MERS, the lag time in the development of therapeutics is likely to take months to years. These facts call for the development of broad-spectrum anti-coronavirus drugs targeting a conserved target site. This review will systematically describe potential broad-spectrum coronavirus fusion inhibitors, including antibodies, protease inhibitors, and peptide fusion inhibitors, along with a discussion of their advantages and disadvantages.
Assuntos
Betacoronavirus/efeitos dos fármacos , Infecções por Coronavirus/tratamento farmacológico , Inibidores de Proteases/uso terapêutico , Inibidores de Proteínas Virais de Fusão/uso terapêutico , Animais , Betacoronavirus/fisiologia , Humanos , Inibidores de Proteases/efeitos adversos , Inibidores de Proteases/farmacologia , SARS-CoV-2 , Inibidores de Proteínas Virais de Fusão/efeitos adversos , Inibidores de Proteínas Virais de Fusão/farmacologia , Internalização do Vírus/efeitos dos fármacosAssuntos
Betacoronavirus/fisiologia , Glicoproteína da Espícula de Coronavírus/fisiologia , Inibidores de Proteínas Virais de Fusão/farmacologia , Internalização do Vírus/efeitos dos fármacos , Sequência de Aminoácidos , Betacoronavirus/efeitos dos fármacos , COVID-19 , Sequência Conservada , Infecções por Coronavirus/tratamento farmacológico , Infecções por Coronavirus/virologia , Humanos , Modelos Moleculares , Pandemias , Pneumonia Viral/tratamento farmacológico , Pneumonia Viral/virologia , Domínios e Motivos de Interação entre Proteínas , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/fisiologia , SARS-CoV-2 , Especificidade da Espécie , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/químicaRESUMO
Human parainfluenza virus 3 (HPIV3) and respiratory syncytial virus (RSV) cause lower respiratory infection in infants and young children. There are no vaccines for these pathogens, and existing treatments have limited or questionable efficacy. Infection by HPIV3 or RSV requires fusion of the viral and cell membranes, a process mediated by a trimeric fusion glycoprotein (F) displayed on the viral envelope. Once triggered, the pre-fusion form of F undergoes a series of conformational changes that first extend the molecule to allow for insertion of the hydrophobic fusion peptide into the target cell membrane and then refold the trimeric assembly into an energetically stable post-fusion state, a process that drives the merger of the viral and host cell membranes. Peptides derived from defined regions of HPIV3 F inhibit infection by HPIV3 by interfering with the structural transitions of the trimeric F assembly. Here we describe lipopeptides derived from the C-terminal heptad repeat (HRC) domain of HPIV3 F that potently inhibit infection by both HPIV3 and RSV. The lead peptide inhibits RSV infection as effectively as does a peptide corresponding to the RSV HRC domain itself. We show that the inhibitors bind to the N-terminal heptad repeat (HRN) domains of both HPIV3 and RSV F with high affinity. Co-crystal structures of inhibitors bound to the HRN domains of HPIV3 or RSV F reveal remarkably different modes of binding in the N-terminal segment of the inhibitor.
Assuntos
Lipopeptídeos/farmacologia , Vírus da Parainfluenza 3 Humana/efeitos dos fármacos , Fragmentos de Peptídeos/farmacologia , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Inibidores de Proteínas Virais de Fusão/farmacologia , Proteínas Virais de Fusão/farmacologia , Sequência de Aminoácidos , Cristalografia por Raios X , Humanos , Lipopeptídeos/metabolismo , Testes de Sensibilidade Microbiana , Vírus da Parainfluenza 3 Humana/química , Fragmentos de Peptídeos/metabolismo , Ligação Proteica , Mucosa Respiratória/virologia , Vírus Sinciciais Respiratórios/química , Inibidores de Proteínas Virais de Fusão/metabolismo , Proteínas Virais de Fusão/metabolismo , Internalização do Vírus/efeitos dos fármacosRESUMO
Continuously emerging highly pathogenic human coronaviruses (HCoVs) remain a major threat to human health, as illustrated in past SARS-CoV and MERS-CoV outbreaks. The development of a drug with broad-spectrum HCoV inhibitory activity would address this urgent unmet medical need. Although previous studies have suggested that the HR1 of HCoV spike (S) protein is an important target site for inhibition against specific HCoVs, whether this conserved region could serve as a target for the development of broad-spectrum pan-CoV inhibitor remains controversial. Here, we found that peptide OC43-HR2P, derived from the HR2 domain of HCoV-OC43, exhibited broad fusion inhibitory activity against multiple HCoVs. EK1, the optimized form of OC43-HR2P, showed substantially improved pan-CoV fusion inhibitory activity and pharmaceutical properties. Crystal structures indicated that EK1 can form a stable six-helix bundle structure with both short α-HCoV and long ß-HCoV HR1s, further supporting the role of HR1 region as a viable pan-CoV target site.
Assuntos
Infecções por Coronavirus/virologia , Coronavirus/efeitos dos fármacos , Coronavirus/metabolismo , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/química , Inibidores de Proteínas Virais de Fusão/química , Inibidores de Proteínas Virais de Fusão/farmacologia , Sequência de Aminoácidos , Animais , Linhagem Celular , Coronavirus/classificação , Coronavirus/genética , Infecções por Coronavirus/tratamento farmacológico , Modelos Animais de Doenças , Humanos , Fusão de Membrana/efeitos dos fármacos , Camundongos , Modelos Moleculares , Peptídeos/química , Peptídeos/farmacologia , Filogenia , Conformação Proteica , Domínios Proteicos , SolubilidadeRESUMO
Recent characterization of broadly neutralizing antibodies (bnAbs) against influenza virus identified the conserved hemagglutinin (HA) stem as a target for development of universal vaccines and therapeutics. Although several stem bnAbs are being evaluated in clinical trials, antibodies are generally unsuited for oral delivery. Guided by structural knowledge of the interactions and mechanism of anti-stem bnAb CR6261, we selected and optimized small molecules that mimic the bnAb functionality. Our lead compound neutralizes influenza A group 1 viruses by inhibiting HA-mediated fusion in vitro, protects mice against lethal and sublethal influenza challenge after oral administration, and effectively neutralizes virus infection in reconstituted three-dimensional cell culture of fully differentiated human bronchial epithelial cells. Cocrystal structures with H1 and H5 HAs reveal that the lead compound recapitulates the bnAb hotspot interactions.
Assuntos
Anticorpos Neutralizantes/química , Materiais Biomiméticos/farmacologia , Vírus da Influenza A Subtipo H1N1/efeitos dos fármacos , Influenza Humana/prevenção & controle , Piperazinas/farmacologia , Piridinas/farmacologia , Tetrazóis/farmacologia , Inibidores de Proteínas Virais de Fusão/farmacologia , Internalização do Vírus/efeitos dos fármacos , Administração Oral , Animais , Materiais Biomiméticos/administração & dosagem , Materiais Biomiméticos/farmacocinética , Brônquios/virologia , Células Cultivadas , Cães , Glicoproteínas de Hemaglutininação de Vírus da Influenza/genética , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Humanos , Células Madin Darby de Rim Canino , Camundongos , Piperazinas/administração & dosagem , Piperazinas/farmacocinética , Piridinas/administração & dosagem , Piridinas/farmacocinética , Mucosa Respiratória/virologia , Tetrazóis/administração & dosagem , Tetrazóis/farmacocinética , Inibidores de Proteínas Virais de Fusão/administração & dosagem , Inibidores de Proteínas Virais de Fusão/farmacocinéticaAssuntos
Vírus Lassa/efeitos dos fármacos , Proteínas do Envelope Viral/antagonistas & inibidores , Proteínas do Envelope Viral/química , Inibidores de Proteínas Virais de Fusão/farmacologia , Vírus Lassa/fisiologia , Fusão de Membrana/efeitos dos fármacos , Domínios Proteicos , Relação Estrutura-Atividade , Inibidores de Proteínas Virais de Fusão/químicaRESUMO
Respiratory syncytial virus (RSV) is a respiratory infection that can cause serious illness, particularly in infants. In this study, we test four different model implementations for the effect of a fusion inhibitor, including one model that combines different drug effects, by fitting the models to data from a study of TMC353121 in African green monkeys. We use mathematical modeling to estimate the drug efficacy parameters, εmax, the maximum efficacy of the drug, and EC50, the drug concentration needed to achieve half the maximum effect. We find that if TMC353121 is having multiple effects on viral kinetics, more detailed data, using different treatment delays, is needed to detect this effect.
Assuntos
Benzimidazóis/uso terapêutico , Modelos Biológicos , Piridinas/uso terapêutico , Infecções por Vírus Respiratório Sincicial/tratamento farmacológico , Vírus Sinciciais Respiratórios/efeitos dos fármacos , Inibidores de Proteínas Virais de Fusão/uso terapêutico , Animais , Benzimidazóis/administração & dosagem , Benzimidazóis/farmacologia , Chlorocebus aethiops , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Esquema de Medicação , Avaliação Pré-Clínica de Medicamentos/métodos , Piridinas/administração & dosagem , Piridinas/farmacologia , Infecções por Vírus Respiratório Sincicial/virologia , Vírus Sinciciais Respiratórios/isolamento & purificação , Vírus Sinciciais Respiratórios/fisiologia , Inibidores de Proteínas Virais de Fusão/administração & dosagem , Inibidores de Proteínas Virais de Fusão/farmacologia , Carga Viral , Replicação Viral/efeitos dos fármacosRESUMO
Human coronavirus 229E (HCoV-229E) infection in infants, elderly people, and immunocompromised patients can cause severe disease, thus calling for the development of effective and safe therapeutics to treat it. Here we reported the design, synthesis and characterization of two peptide-based membrane fusion inhibitors targeting HCoV-229E spike protein heptad repeat 1 (HR1) and heptad repeat 2 (HR2) domains, 229E-HR1P and 229E-HR2P, respectively. We found that 229E-HR1P and 229E-HR2P could interact to form a stable six-helix bundle and inhibit HCoV-229E spike protein-mediated cell-cell fusion with IC50 of 5.7 and 0.3 µM, respectively. 229E-HR2P effectively inhibited pseudotyped and live HCoV-229E infection with IC50 of 0.5 and 1.7 µM, respectively. In a mouse model, 229E-HR2P administered intranasally could widely distribute in the upper and lower respiratory tracts and maintain its fusion-inhibitory activity. Therefore, 229E-HR2P is a promising candidate for further development as an antiviral agent for the treatment and prevention of HCoV-229E infection.
Assuntos
Coronavirus Humano 229E/efeitos dos fármacos , Peptídeos/farmacologia , Domínios e Motivos de Interação entre Proteínas/efeitos dos fármacos , Glicoproteína da Espícula de Coronavírus/antagonistas & inibidores , Glicoproteína da Espícula de Coronavírus/química , Inibidores de Proteínas Virais de Fusão/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Células Gigantes/efeitos dos fármacos , Células Gigantes/virologia , Humanos , Fusão de Membrana , Camundongos , Peptídeos/química , Ligação Proteica , Inibidores de Proteínas Virais de Fusão/químicaRESUMO
Current anti-hepatitis B virus (HBV) agents including interferons and nucleos(t)ide analogs efficiently suppress HBV infection. However, as it is difficult to eliminate HBV from chronically infected liver, alternative anti-HBV agents targeting a new molecule are urgently needed. In this study, we applied a chemical array to high throughput screening of small molecules that interacted with sodium taurocholate cotransporting polypeptide (NTCP), an entry receptor for HBV. From approximately 30,000 compounds, we identified 74 candidates for NTCP interactants, and five out of these were shown to inhibit HBV infection in cell culture. One of such compound, NPD8716, a coumarin derivative, interacted with NTCP and inhibited HBV infection without causing cytotoxicity. Consistent with its NTCP interaction capacity, this compound was shown to block viral attachment to host hepatocytes. NPD8716 also prevented the infection with hepatitis D virus, but not hepatitis C virus, in agreement with NPD8716 specifically inhibiting NTCP-mediated infection. Analysis of derivative compounds showed that the anti-HBV activity of compounds was apparently correlated with the affinity to NTCP and the capacity to impair NTCP-mediated bile acid uptake. These results are the first to show that the chemical array technology represents a powerful platform to identify novel viral entry inhibitors.