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Upon infection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), patients with critical coronavirus disease 2019 (COVID-19) present with life-threatening respiratory distress, pulmonary damage, and cytokine storm. One unexplored component in COVID-19 is the neuropeptide calcitonin gene-related peptide (CGRP), which is highly abundant in the airways and could converge in multiple aspects of COVID-19-related pulmonary pathophysiology. Whether CGRP affects SARS-CoV-2 infection directly remains elusive. We show that in critical COVID-19 patients, CGRP is increased in both plasma and lungs. Importantly, CGRP pulmonary levels are elevated in early SARS-CoV-2-positive patients and restored to baseline upon subsequent viral clearance in SARS-CoV-2-negative patients. We further show that CGRP and its stable analog SAX directly inhibit infection of bronchial Calu-3 epithelial cells with SARS-CoV-2 Omicron and Alpha variants in a dose-dependent manner. Both pre- and post-infection treatments with CGRP and/or SAX are enough to block SARS-CoV-2 productive infection of Calu-3 cells. CGRP-mediated inhibition occurs via activation of the CGRP receptor and involves down-regulation of both SARS-CoV-2 entry receptors at the surface of Calu-3 cells. Together, we propose that increased pulmonary CGRP mediates beneficial viral clearance in critical COVID-19 patients by directly inhibiting SARS-CoV-2 propagation. Hence, CGRP-based interventions could be harnessed for management of COVID-19.IMPORTANCEThe neuropeptide CGRP is highly abundant in the airways. Due to its immunomodulatory, vasodilatory, and anti-viral functions, CGRP could affect multiple aspects of COVID-19-related pulmonary pathophysiology. Yet, the interplay between CGRP and SARS-CoV-2 during COVID-19 remains elusive. Herein, we show that pulmonary levels of CGRP are increased in critical COVID-19 patients, at an early stage of their disease when patients are SARS-CoV-2-positive. Upon subsequent viral clearance, CGRP levels are restored to baseline in SARS-CoV-2-negative patients. We further show that pre- and post-infection treatments with CGRP directly inhibit infection of Calu-3 bronchial epithelial cells with SARS -CoV-2, via activation of the CGRP receptor leading to decreased expression of both SARS-CoV-2 entry receptors. Together, we propose that increased pulmonary CGRP is beneficial in COVID-19, as CGRP-mediated inhibition of SARS-CoV-2 infection could contribute to viral clearance in critical COVID-19 patients. Accordingly, CGRP-based formulations could be useful for COVID-19 management.
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The role of the mucosal pulmonary antibody response in coronavirus disease 2019 (COVID-19) outcome remains unclear. Here, we found that in bronchoalveolar lavage (BAL) samples from 48 patients with severe COVID-19-infected with the ancestral Wuhan virus, mucosal IgG and IgA specific for S1, receptor-binding domain (RBD), S2, and nucleocapsid protein (NP) emerged in BAL containing viruses early in infection and persist after virus elimination, with more IgA than IgG for all antigens tested. Furthermore, spike-IgA and spike-IgG immune complexes were detected in BAL, especially when the lung virus has been cleared. BAL IgG and IgA recognized the four main RBD variants. BAL neutralizing titers were higher early in COVID-19 when virus replicates in the lung than later in infection after viral clearance. Patients with fatal COVID-19, in contrast to survivors, developed higher levels of mucosal spike-specific IgA than IgG but lost neutralizing activities over time and had reduced IL-1ß in the lung. Altogether, mucosal spike and NP-specific IgG and S1-specific IgA persisting after lung severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) clearance and low pulmonary IL-1ß correlate with COVID-19 fatal outcome. Thus, mucosal SARS-CoV-2-specific antibodies may have adverse functions in addition to protective neutralization. Highlights: Mucosal pulmonary antibody response in COVID-19 outcome remains unclear. We show that in severe COVID-19 patients, mucosal pulmonary non-neutralizing SARS-CoV-2 IgA persit after viral clearance in the lung. Furthermore, low lung IL-1ß correlate with fatal COVID-19. Altogether, mucosal IgA may exert harmful functions beside protective neutralization.
Assuntos
COVID-19 , Interleucina-1beta/metabolismo , SARS-CoV-2 , Anticorpos Antivirais , Complexo Antígeno-Anticorpo , Estudos Transversais , Humanos , Imunoglobulina A , Imunoglobulina G , Pulmão , Proteínas do Nucleocapsídeo , Glicoproteína da Espícula de CoronavírusRESUMO
SARS-CoV-2, although not being a circulatory virus, spread from the respiratory tract resulting in multiorgan failures and thrombotic complications, the hallmarks of fatal COVID-19. A convergent contributor could be platelets that beyond hemostatic functions can carry infectious viruses. Here, we profiled 52 patients with severe COVID-19 and demonstrated that circulating platelets of 19 out 20 non-survivor patients contain SARS-CoV-2 in robust correlation with fatal outcome. Platelets containing SARS-CoV-2 might originate from bone marrow and lung megakaryocytes (MKs), the platelet precursors, which were found infected by SARS-CoV-2 in COVID-19 autopsies. Accordingly, MKs undergoing shortened differentiation and expressing anti-viral IFITM1 and IFITM3 RNA as a sign of viral sensing were enriched in the circulation of deadly COVID-19. Infected MKs reach the lung concomitant with a specific MK-related cytokine storm rich in VEGF, PDGF and inflammatory molecules, anticipating fatal outcome. Lung macrophages capture SARS-CoV-2-containing platelets in vivo. The virus contained by platelets is infectious as capture of platelets carrying SARS-CoV-2 propagates infection to macrophages in vitro, in a process blocked by an anti-GPIIbIIIa drug. Altogether, platelets containing infectious SARS-CoV-2 alter COVID-19 pathogenesis and provide a powerful fatality marker. Clinical targeting of platelets might prevent viral spread, thrombus formation and exacerbated inflammation at once and increase survival in COVID-19.
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COVID-19 , Trombose , Plaquetas , Humanos , Pulmão , Megacariócitos , Proteínas de Membrana , Proteínas de Ligação a RNA , SARS-CoV-2RESUMO
Hepatitis C virus (HCV) infection and alcohol abuse are leading causes of chronic liver disease and frequently coexist in patients. The unfolded protein response (UPR), a cellular stress response ranging along a spectrum from cytoprotection to apoptosis commitment, has emerged as a major contributor to human diseases including liver injuries. However, the literature contains conflicting reports as to whether HCV and ethanol activate the UPR and which UPR genes are involved. Here we have used primary human hepatocytes (PHH) to reassess this issue and address combined impacts. In this physiologically relevant model, either stressor activated a chronic complete UPR. However, the levels of UPR gene induction were only modest in the case of HCV infection. Moreover, when combined to the strong stressor thapsigargin, ethanol exacerbated the activation of pro-apoptotic genes whereas HCV tended to limit the induction of key UPR genes. The UPR resulting from HCV plus ethanol was comparable to that induced by ethanol alone with the notable exception of three pro-survival genes the expressions of which were selectively enhanced by HCV. Interestingly, HCV genome replication was maintained at similar levels in PHH exposed to ethanol. In conclusion, while both HCV and alcohol activate the hepatocellular UPR, only HCV manipulates UPR signalling in the direction of a cytoprotective response, which appears as a viral strategy to spare its own replication.
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Etanol/toxicidade , Hepatite C Crônica/metabolismo , Hepatócitos/metabolismo , Fígado/metabolismo , Resposta a Proteínas não Dobradas , Apoptose , Linhagem Celular , Hepacivirus/fisiologia , Hepatite C Crônica/patologia , Hepatócitos/patologia , Humanos , Fígado/patologia , Transdução de Sinais , Replicação ViralRESUMO
BACKGROUND: Familial hypercholesterolemia type IIA (FH) is due to mutations in the low-density lipoprotein receptor (LDLR) resulting in elevated levels of low-density lipoprotein cholesterol (LDL-c) in plasma and in premature cardiovascular diseases. As hepatocytes are the only cells capable of metabolizing cholesterol, they are therefore the target cells for cell/gene therapy approaches in the treatment of lipid metabolism disorders. Furthermore, the LDLR has been reported to be involved in hepatitis C virus (HCV) entry into hepatocytes; however, its role in the virus infection cycle is still disputed. METHODS: We generated induced pluripotent stem cells (iPSCs) from a homozygous LDLR-null FH-patient (FH-iPSCs). We constructed a correction cassette bearing LDLR cDNA under the control of human hepatic apolipoprotein A2 promoter that targets the adeno-associated virus integration site AAVS1. We differentiated both FH-iPSCs and corrected FH-iPSCs (corr-FH-iPSCs) into hepatocytes to study statin-mediated regulation of genes involved in cholesterol metabolism. Upon HCV particle inoculation, viral replication and production were quantified in these cells. RESULTS: We showed that FH-iPSCs displayed the disease phenotype. Using homologous recombination mediated by the CRISPR/Cas9 system, FH-iPSCs were genetically corrected by the targeted integration of a correction cassette at the AAVS1 locus. Both FH-iPSCs and corr-FH-iPSCs were then differentiated into functional polarized hepatocytes using a stepwise differentiation approach (FH-iHeps and corr-FH-iHeps). The correct insertion and expression of the correction cassette resulted in restoration of LDLR expression and function (LDL-c uptake) in corr-FH-iHeps. We next demonstrated that pravastatin treatment increased the expression of genes involved in cholesterol metabolism in both cell models. Moreover, LDLR expression and function were also enhanced in corr-FH-iHeps after pravastatin treatment. Finally, we demonstrated that both FH-iHeps and corr-FH-iHeps were as permissive to viral infection as primary human hepatocytes but that virus production in FH-iHeps was significantly decreased compared to corr-FH-iHeps, suggesting a role of the LDLR in HCV morphogenesis. CONCLUSIONS: Our work provides the first LDLR-null FH cell model and its corrected counterpart to study the regulation of cholesterol metabolism and host determinants of HCV life cycle, and a platform to screen drugs for treating dyslipidemia and HCV infection.
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Sistemas CRISPR-Cas/genética , Edição de Genes , Hepatite C/patologia , Hiperlipoproteinemia Tipo II/patologia , Receptores de LDL/genética , Antivirais/farmacologia , Antivirais/uso terapêutico , Apolipoproteína A-II/genética , Diferenciação Celular , Colesterol/metabolismo , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Hepatite C/tratamento farmacológico , Hepatite C/virologia , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Hiperlipoproteinemia Tipo II/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Fenótipo , Plasmídeos/genética , Plasmídeos/metabolismo , Regiões Promotoras Genéticas , Pró-Proteína Convertase 9/genética , Pró-Proteína Convertase 9/metabolismo , Receptores de LDL/metabolismo , Sofosbuvir/farmacologia , Sofosbuvir/uso terapêutico , Proteína de Ligação a Elemento Regulador de Esterol 2/genética , Proteína de Ligação a Elemento Regulador de Esterol 2/metabolismoRESUMO
Recent emergence of direct-acting antivirals (DAAs) targeting hepatitis C virus (HCV) proteins has considerably enhanced the success of antiviral therapy. However, the appearance of DAA-resistant-associated variants is a cause of treatment failure, and the high cost of DAAs renders the therapy not accessible in countries with inadequate medical infrastructures. Therefore, the search for new inhibitors with a lower cost of production should be pursued. In this context, the crude extract of Juncus maritimus Lam. was shown to exhibit high antiviral activity against HCV in cell culture. Bio-guided fractionation allowed the isolation and identification of the active compound, dehydrojuncusol. A time-of-addition assay showed that dehydrojuncusol significantly inhibited HCV infection when added after virus inoculation of HCV genotype 2a (50% effective concentration [EC50] = 1.35 µM). This antiviral activity was confirmed with an HCV subgenomic replicon, and no effect on HCV pseudoparticle entry was observed. Antiviral activity of dehydrojuncusol was also demonstrated in primary human hepatocytes. No in vitro toxicity was observed at active concentrations. Dehydrojuncusol is also efficient on HCV genotype 3a and can be used in combination with sofosbuvir. Interestingly, dehydrojuncusol was able to inhibit RNA replication of two frequent daclatasvir-resistant mutants (L31M or Y93H in NS5A). Finally, mutants resistant to dehydrojuncusol were obtained and showed that the HCV NS5A protein is the target of the molecule. In conclusion, dehydrojuncusol, a natural compound extracted from J. maritimus, inhibits infection of different HCV genotypes by targeting the NS5A protein and is active against resistant HCV variants frequently found in patients with treatment failure.IMPORTANCE Tens of millions of people are infected with hepatitis C virus (HCV) worldwide. Recently marketed direct-acting antivirals (DAAs) targeting HCV proteins have enhanced the efficacy of treatment. However, due to its high cost, this new therapy is not accessible to the vast majority of infected patients. Furthermore, treatment failures have also been reported due to the appearance of viral resistance. Here, we report on the identification of a new HCV inhibitor, dehydrojuncusol, that targets HCV NS5A and is able to inhibit RNA replication of replicons harboring resistance mutations to anti-NS5A DAAs used in current therapy. Dehydrojuncusol is a natural compound isolated from Juncus maritimus, a halophilic plant species that is very common in coastlines worldwide. This molecule might serve as a lead for the development of a new therapy that is more accessible to hepatitis C patients in the future.
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Hepacivirus/efeitos dos fármacos , Fenantrenos/farmacologia , Replicação Viral/efeitos dos fármacos , Antivirais/farmacologia , Linhagem Celular , Farmacorresistência Viral/genética , Genótipo , Células HEK293 , Hepacivirus/genética , Hepatite C/genética , Hepatite C/virologia , Hepatite C Crônica/virologia , Hepatócitos/virologia , Humanos , Fenantrenos/metabolismo , Fenetilaminas/farmacologia , Extratos Vegetais/farmacologia , Inibidores de Proteases/farmacologia , Replicon/efeitos dos fármacos , RizomaRESUMO
OBJECTIVE: Recently approved direct acting antivirals provide transformative therapies for chronic hepatitis C virus (HCV) infection. The major clinical challenge remains to identify the undiagnosed patients worldwide, many of whom live in low-income and middle-income countries, where access to nucleic acid testing remains limited. The aim of this study was to develop and validate a point-of-care (PoC) assay for the qualitative detection of HCV RNA. DESIGN: We developed a PoC assay for the qualitative detection of HCV RNA on the PCR Genedrive instrument. We validated the Genedrive HCV assay through a case-control study comparing results with those obtained with the Abbott RealTime HCV test. RESULTS: The PoC assay identified all major HCV genotypes, with a limit of detection of 2362 IU/mL (95% CI 1966 to 2788). Using 422 patients chronically infected with HCV and 503 controls negative for anti-HCV and HCV RNA, the Genedrive HCV assay showed 98.6% sensitivity (95% CI 96.9% to 99.5%) and 100% specificity (95% CI 99.3% to 100%) to detect HCV. In addition, melting peak ratiometric analysis demonstrated proof-of-principle for semiquantification of HCV. The test was further validated in a real clinical setting in a resource-limited country. CONCLUSION: We report a rapid, simple, portable and accurate PoC molecular test for HCV, with sensitivity and specificity that fulfils the recent FIND/WHO Target Product Profile for HCV decentralised testing in low-income and middle-income countries. This Genedrive HCV assay may positively impact the continuum of HCV care from screening to cure by supporting real-time treatment decisions. TRIAL REGISTRATION NUMBER: NCT02992184 .
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Hepacivirus/genética , Hepatite C Crônica/virologia , RNA Viral/genética , Carga Viral/métodos , Adulto , Idoso , Estudos de Casos e Controles , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Sistemas Automatizados de Assistência Junto ao Leito , Reação em Cadeia da Polimerase/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Hepatitis C virus (HCV) is a leading cause of liver diseases including the development of hepatocellular carcinoma (HCC). Particularly, core protein has been involved in HCV-related liver pathologies. However, the impact of HCV core on signaling pathways supporting the genesis of HCC remains largely elusive. To decipher the host cell signaling pathways involved in the oncogenic potential of HCV core, a global quantitative phosphoproteomic approach was carried out. This study shed light on novel differentially phosphorylated proteins, in particular several components involved in translation. Among the eukaryotic initiation factors that govern the translational machinery, 4E-BP1 represents a master regulator of protein synthesis that is associated with the development and progression of cancers due to its ability to increase protein expression of oncogenic pathways. Enhanced levels of 4E-BP1 in non-modified and phosphorylated forms were validated in human hepatoma cells and in mouse primary hepatocytes expressing HCV core, in the livers of HCV core transgenic mice as well as in HCV-infected human primary hepatocytes. The contribution of HCV core in carcinogenesis and the status of 4E-BP1 expression and phosphorylation were studied in HCV core/Myc double transgenic mice. HCV core increased the levels of 4E-BP1 expression and phosphorylation and significantly accelerated the onset of Myc-induced tumorigenesis in these double transgenic mice. These results reveal a novel function of HCV core in liver carcinogenesis potentiation. They position 4E-BP1 as a tumor-specific target of HCV core and support the involvement of the 4E-BP1/eIF4E axis in hepatocarcinogenesis.
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Hepacivirus , Hepatite C Crônica/tratamento farmacológico , Retratamento/métodos , Sofosbuvir/administração & dosagem , Proteínas não Estruturais Virais/antagonistas & inibidores , Antivirais/administração & dosagem , Antivirais/efeitos adversos , Antivirais/classificação , Farmacorresistência Viral/genética , Feminino , Genoma Viral , Hepacivirus/efeitos dos fármacos , Hepacivirus/genética , Hepatite C Crônica/virologia , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Tempo , Falha de Tratamento , Resultado do TratamentoRESUMO
In hepatitis C virus (HCV) polyprotein sequence, core protein terminates with E1 envelope signal peptide. Cleavage by signal peptidase (SP) separates E1 from the complete form of core protein, anchored in the endoplasmic reticulum (ER) membrane by the signal peptide. Subsequent cleavage of the signal peptide by signal-peptide peptidase (SPP) releases the mature form of core protein, which preferentially relocates to lipid droplets. Both of these cleavages are required for the HCV infectious cycle, supporting the idea that HCV assembly begins at the surface of lipid droplets, yet SPP-catalyzed cleavage is dispensable for initiation of budding in the ER. Here we have addressed at what step(s) of the HCV infectious cycle SP-catalyzed cleavage at the core-E1 junction is required. Taking advantage of the sole system that has allowed visualization of HCV budding events in the ER lumen of mammalian cells, we showed that, unexpectedly, mutations abolishing this cleavage did not prevent but instead tended to promote the initiation of viral budding. Moreover, even though no viral particles were released from Huh-7 cells transfected with a full-length HCV genome bearing these mutations, intracellular viral particles containing core protein protected by a membrane envelope were formed. These were visualized by electron microscopy as capsid-containing particles with a diameter of about 70 nm and 40 nm before and after delipidation, respectively, comparable to intracellular wild-type particle precursors except that they were non-infectious. Thus, our results show that SP-catalyzed cleavage is dispensable for HCV budding per se, but is required for the viral particles to acquire their infectivity and secretion. These data support the idea that HCV assembly occurs in concert with budding at the ER membrane. Furthermore, capsid-containing particles did not accumulate in the absence of SP-catalyzed cleavage, suggesting the quality of newly formed viral particles is controlled before secretion.
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Ácido Aspártico Endopeptidases/metabolismo , Hepacivirus/metabolismo , Proteínas do Core Viral/metabolismo , Ácido Aspártico Endopeptidases/genética , Linhagem Celular Tumoral , Retículo Endoplasmático/metabolismo , Hepacivirus/genética , Humanos , Gotículas Lipídicas/metabolismo , Sinais Direcionadores de Proteínas , Proteínas do Core Viral/genética , Montagem de VírusRESUMO
OBJECTIVE: HCV is intimately linked with the liver lipid metabolism, devoted to the efflux of triacylglycerols stored in lipid droplets (LDs) in the form of triacylglycerol-rich very-low-density lipoproteins (VLDLs): (i) the most infectious HCV particles are those of lowest density due to association with triacylglycerol-rich lipoproteins and (ii) HCV-infected patients frequently develop hepatic steatosis (increased triacylglycerol storage). The recent identification of lysophosphatidylcholine acyltransferase 1 (LPCAT1) as an LD phospholipid-remodelling enzyme prompted us to investigate its role in liver lipid metabolism and HCV infectious cycle. DESIGN: Huh-7.5.1 cells and primary human hepatocytes (PHHs) were infected with JFH1-HCV. LPCAT1 depletion was achieved by RNA interference. Cells were monitored for LPCAT1 expression, lipid metabolism and HCV production and infectivity. The density of viral particles was assessed by isopycnic ultracentrifugation. RESULTS: Upon HCV infection, both Huh-7.5.1 cells and PHH had decreased levels of LPCAT1 transcript and protein, consistent with transcriptional downregulation. LPCAT1 depletion in either naive or infected Huh-7.5.1 cells resulted in altered lipid metabolism characterised by LD remodelling, increased triacylglycerol storage and increased secretion of VLDL. In infected Huh-7.5.1 cells or PHH, LPCAT1 depletion increased production of the viral particles of lowest density and highest infectivity. CONCLUSIONS: We have identified LPCAT1 as a modulator of liver lipid metabolism downregulated by HCV, which appears as a viral strategy to increase the triacylglycerol content and hence infectivity of viral particles. Targeting this metabolic pathway may represent an attractive therapeutic approach to reduce both the viral titre and hepatic steatosis.
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1-Acilglicerofosfocolina O-Aciltransferase/metabolismo , Hepacivirus/metabolismo , Hepatócitos/metabolismo , Metabolismo dos Lipídeos , Vírion/metabolismo , Western Blotting , Células Cultivadas , Regulação para Baixo , Humanos , Microscopia Confocal , RNA , Interferência de RNA , Reação em Cadeia da Polimerase em Tempo Real , Carga Viral , Replicação ViralRESUMO
Quercetin is a natural flavonoid, which has been shown to have anti hepatitis C virus (HCV) properties. However, the exact mechanisms whereby quercetin impacts the HCV life cycle are not fully understood. We assessed the effect of quercetin on different steps of the HCV life cycle in Huh-7.5 cells and primary human hepatocytes (PHH) infected with HCVcc. In both cell types, quercetin significantly decreased i) the viral genome replication; ii) the production of infectious HCV particles and iii) the specific infectivity of the newly produced viral particles (by 85% and 92%, Huh7.5 and PHH respectively). In addition, when applied directly on HCV particles, quercetin reduced their infectivity by 65%, suggesting that it affects the virion integrity. Interestingly, the HCV-induced up-regulation of diacylglycerol acyltransferase (DGAT) and the typical localization of the HCV core protein to the surface of lipid droplets, known to be mediated by DGAT, were both prevented by quercetin. In conclusion, quercetin appears to have direct and host-mediated antiviral effects against HCV.
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Hepacivirus/efeitos dos fármacos , Hepatócitos/efeitos dos fármacos , Quercetina/farmacologia , Replicação Viral/efeitos dos fármacos , Carcinoma Hepatocelular/patologia , Carcinoma Hepatocelular/virologia , Linhagem Celular Tumoral , Células Cultivadas , Diacilglicerol O-Aciltransferase/genética , Diacilglicerol O-Aciltransferase/metabolismo , Expressão Gênica/efeitos dos fármacos , Hepacivirus/genética , Hepacivirus/fisiologia , Hepatócitos/metabolismo , Hepatócitos/virologia , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Humanos , Gotículas Lipídicas/efeitos dos fármacos , Gotículas Lipídicas/metabolismo , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Vírion/efeitos dos fármacos , Vírion/genética , Vírion/fisiologia , Replicação Viral/genéticaRESUMO
UNLABELLED: Aminoquinolines and piperazines, linked or not, have been used successfully to treat malaria, and some molecules of this family also exhibit antiviral properties. Here we tested several derivatives of 4-aminoquinolines and piperazines for their activity against hepatitis C virus (HCV). We screened 11 molecules from three different families of compounds, and we identified anti-HCV activity in cell culture for six of them. Of these, we selected a compound (B5) that is currently ending clinical phase I evaluation for neurodegenerative diseases. In hepatoma cells, B5 inhibited HCV infection in a pangenotypic and dose-dependent manner, and its antiviral activity was confirmed in primary hepatocytes. B5 also inhibited infection by pseudoparticles expressing HCV envelope glycoproteins E1 and E2, and we demonstrated that it affects a postattachment stage of the entry step. Virus with resistance to B5 was selected by sequential passage in the presence of the drug, and reverse genetics experiments indicated that resistance was conferred mainly by a single mutation in the putative fusion peptide of E1 envelope glycoprotein (F291I). Furthermore, analyses of the effects of other closely related compounds on the B5-resistant mutant suggest that B5 shares a mode of action with other 4-aminoquinoline-based molecules. Finally, mice with humanized liver that were treated with B5 showed a delay in the kinetics of the viral infection. In conclusion, B5 is a novel interesting anti-HCV molecule that could be used to decipher the early steps of the HCV life cycle. IMPORTANCE: In the last 4 years, HCV therapy has been profoundly improved with the approval of direct-acting antivirals in clinical practice. Nevertheless, the high costs of these drugs limit access to therapy in most countries. The present study reports the identification and characterization of a compound (B5) that inhibits HCV propagation in cell culture and is currently ending clinical phase I evaluation for neurodegenerative diseases. This molecule inhibits the HCV life cycle by blocking virus entry. Interestingly, after selection of drug-resistant virus, a resistance mutation in the putative fusion peptide of E1 envelope glycoprotein was identified, indicating that B5 could be used to further investigate the fusion mechanism. Furthermore, mice with humanized liver treated with B5 showed a delay in the kinetics of the viral infection. In conclusion, B5 is a novel interesting anti-HCV molecule that could be used to decipher the early steps of the HCV life cycle.
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Aminoquinolinas/farmacologia , Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Aminoquinolinas/química , Aminoquinolinas/isolamento & purificação , Animais , Antivirais/química , Antivirais/isolamento & purificação , Células Cultivadas , Modelos Animais de Doenças , Avaliação Pré-Clínica de Medicamentos , Farmacorresistência Viral , Hepatite C/tratamento farmacológico , Hepatócitos/virologia , Humanos , Camundongos , Camundongos SCID , Modelos Moleculares , Estrutura Molecular , Mutação de Sentido Incorreto , Genética Reversa , Resultado do Tratamento , Proteínas do Envelope Viral/genética , Internalização do Vírus/efeitos dos fármacosRESUMO
IMPORTANCE: Data on long-term immune responses to hepatitis B virus (HBV) vaccination in adults with human immunodeficiency virus 1 (HIV-1) infection are scarce. OBJECTIVE: To compare long-term (up to month 42) immune responses to the standard HBV vaccination regimen with a 4-injection intramuscular double-dose regimen and a 4-injection intradermal low-dose regimen. DESIGN, SETTING, AND PARTICIPANTS: The phase 3, open-label, multicenter parallel-group (1:1:1 allocation ratio) randomized clinical trial was conducted from June 28, 2007, to October 23, 2008, at 33 centers in France. Participants included 437 HBV-seronegative adults with HIV-1 and CD4 cell counts of more than 200/µL. Follow-up was extended to September 12, 2012, and data were assessed from February 13, 2015, to January 22, 2016. The analysis was imputed for an intention-to-treat population. INTERVENTIONS: Patients were randomly assigned to receive 3 intramuscular standard-dose (20-µg) injections of recombinant HBV vaccine at weeks 0, 4, and 24 (IM20 × 3 group) (145 participants), 4 intramuscular double-dose (40-µg) injections at weeks 0, 4, 8, and 24 (IM40 × 4 group) (148 participants), or 4 intradermal low-dose (4-µg) injections at weeks 0, 4, 8, and 24 (ID4 × 4 group) (144 participants). MAIN OUTCOMES AND MEASURES: The previously published primary trial end point was the percentage of responders at week 28, defined as patients with hepatitis B surface antibody (HBsAb) levels of at least 10 mIU/mL among patients who received at least 1 vaccine dose. The secondary trial end points included the percentage of responders at months 18, 30, and 42 and the duration of response from week 28. Multiple imputation was used to address missing measurements during the follow-up. RESULTS: Among the 437 patients randomized, 426 received at least 1 dose of vaccine. Of these, 287 were men (67.4%) and they had a mean (SD) age of 42.9 (9.7) years. The percentage of responders at month 42 was 41% (95% CI, 33%-49%) in the IM20 × 3 group, 71% (95% CI, 64%-79%) in the IM40 × 4 group (P < .001 vs the IM20 × 3 group), and 44% (95% CI, 35%-53%) in the ID4 × 4 group (P = .64 vs IM20 × 3 group). Fifteen percent of the patients had HBsAb titers of less than 10 mIU/mL at 33.1 months in the IM40 × 4 group, 8.7 months in the IM20 × 3 group, and 6.8 months in the ID4 × 4 group. CONCLUSIONS AND RELEVANCE: In this follow-up of a trial of adults with HIV-1 infection, the IM40 × 4 regimen of recombinant HBV vaccine improved long-term immune response compared with the standard regimen. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00480792.
Assuntos
Infecções por HIV/imunologia , HIV-1 , Anticorpos Anti-Hepatite B/sangue , Vacinas contra Hepatite B/administração & dosagem , Vacinas contra Hepatite B/imunologia , Hepatite B/imunologia , Hepatite B/prevenção & controle , Adulto , Biomarcadores/sangue , Feminino , Seguimentos , França , Humanos , Injeções Intradérmicas/métodos , Injeções Intramusculares/métodos , Masculino , Pessoa de Meia-Idade , Método Simples-Cego , Resultado do Tratamento , Vacinação/métodosRESUMO
UNLABELLED: Despite the validation of direct-acting antivirals for hepatitis C treatment, the discovery of new compounds with different modes of action may still be of importance for the treatment of special patient populations. We recently identified a natural molecule, epigallocatechin-3-gallate (EGCG), as an inhibitor of hepatitis C virus (HCV) targeting the viral particle. The aim of this work was to discover new natural compounds with higher anti-HCV activity than that of EGCG and determine their mode of action. Eight natural molecules with structure similarity to EGCG were selected. HCV JFH1 in cell culture and HCV pseudoparticle systems were used to determine the antiviral activity and mechanism of action of the compounds. We identified delphinidin, a polyphenol belonging to the anthocyanidin family, as a new inhibitor of HCV entry. Delphinidin inhibits HCV entry in a pangenotypic manner by acting directly on the viral particle and impairing its attachment to the cell surface. Importantly, it is also active against HCV in primary human hepatocytes, with no apparent cytotoxicity and in combination with interferon and boceprevir in cell culture. Different approaches showed that neither aggregation nor destruction of the particle occurred. Cryo-transmission electron microscopy observations of HCV pseudoparticles treated with delphinidin or EGCG showed a bulge on particles that was not observed under control conditions. In conclusion, EGCG and delphinidin inhibit HCV entry by a new mechanism, i.e., alteration of the viral particle structure that impairs its attachment to the cell surface. IMPORTANCE: In this article, we identify a new inhibitor of hepatitis C virus (HCV) infection, delphinidin, that prevents HCV entry. This natural compound, a plant pigment responsible for the blue-purple color of flowers and berries, belongs to the flavonoid family, like the catechin EGCG, the major component present in green tea extract, which is also an inhibitor of HCV entry. We studied the mode of action of these two compounds against HCV and demonstrated that they both act directly on the virus, inducing a bulging of the viral envelope. This deformation might be responsible for the observed inhibition of virus attachment to the cell surface. The discovery of such HCV inhibitors with an unusual mode of action is important to better characterize the mechanism of HCV entry into hepatocytes and to help develop a new class of HCV entry inhibitors.
Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Hepacivirus/fisiologia , Polifenóis/farmacologia , Internalização do Vírus/efeitos dos fármacos , Antocianinas/administração & dosagem , Antocianinas/farmacologia , Antivirais/administração & dosagem , Catequina/análogos & derivados , Catequina/farmacologia , Linhagem Celular , Microscopia Crioeletrônica , Avaliação Pré-Clínica de Medicamentos , Células HEK293 , Hepacivirus/ultraestrutura , Hepatócitos/efeitos dos fármacos , Hepatócitos/virologia , Humanos , Interferon-alfa/administração & dosagem , Polifenóis/administração & dosagem , Prolina/administração & dosagem , Prolina/análogos & derivadosRESUMO
In the model of Huh-7.5.1 hepatocyte cells infected by the JFH1 hepatitis C virus (HCV) strain, transcriptomic and proteomic studies have revealed modulations of pathways governing mainly apoptosis and cell cycling. Differences between transcriptomic and proteomic studies pointed to regulations occurring at the posttranscriptional level, including the control of mRNA translation. In this study, we investigated at the genome-wide level the translational regulation occurring during HCV infection. Sucrose gradient ultracentrifugation followed by microarray analysis was used to identify translationally regulated mRNAs (mRNAs associated with ribosomes) from JFH1-infected and uninfected Huh-7.5.1 cells. Translationally regulated mRNAs were found to correspond to genes enriched in specific pathways, including vesicular transport and posttranscriptional regulation. Interestingly, the strongest translational regulation was found for mRNAs encoding proteins involved in pre-mRNA splicing, mRNA translation, and protein folding. Strikingly, these pathways were not previously identified, through transcriptomic studies, as being modulated following HCV infection. Importantly, the observed changes in host mRNA translation were directly due to HCV replication rather than to HCV entry, since they were not observed in JFH1-infected Huh-7.5.1 cells treated with a potent HCV NS3 protease inhibitor. Overall, this study highlights the need to consider, beyond transcriptomic or proteomic studies, the modulation of host mRNA translation as an important aspect of HCV infection.
Assuntos
Hepacivirus/patogenicidade , Hepatócitos/metabolismo , Hepatócitos/virologia , Biossíntese de Proteínas , Linhagem Celular Tumoral , Centrifugação com Gradiente de Concentração , Genoma , Hepacivirus/genética , Hepacivirus/metabolismo , Hepatite C/virologia , Interações Hospedeiro-Patógeno , Humanos , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Proteômica , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribossomos/genética , Ribossomos/metabolismo , Replicação ViralRESUMO
Exposure to hepatitis C virus (HCV) typically results in chronic infection that leads to progressive liver disease ranging from mild inflammation to severe fibrosis and cirrhosis as well as primary liver cancer. HCV triggers innate immune signaling within the infected hepatocyte, a first step in mounting of the adaptive response against HCV infection. Persistent inflammation is strongly associated with liver tumorigenesis. The goal of our work was to investigate the initiation of the inflammatory processes triggered by HCV viral proteins in their host cell and their possible link with HCV-related liver cancer. We report a dramatic upregulation of the lymphotoxin signaling pathway and more specifically of lymphotoxin-ß in tumors of the FL-N/35 HCV-transgenic mice. Lymphotoxin expression is accompanied by activation of NF-κB, neosynthesis of chemokines and intra-tumoral recruitment of mononuclear cells. Spectacularly, IKKß inactivation in FL-N/35 mice drastically reduces tumor incidence. Activation of lymphotoxin-ß pathway can be reproduced in several cellular models, including the full length replicon and HCV-infected primary human hepatocytes. We have identified NS5B, the HCV RNA dependent RNA polymerase, as the viral protein responsible for this phenotype and shown that pharmacological inhibition of its activity alleviates activation of the pro-inflammatory pathway. These results open new perspectives in understanding the inflammatory mechanisms linked to HCV infection and tumorigenesis.
Assuntos
Hepacivirus/enzimologia , Neoplasias Hepáticas/metabolismo , Linfócitos/imunologia , Linfotoxina-beta/metabolismo , RNA Polimerase Dependente de RNA/metabolismo , Animais , Linhagem Celular , Quimiocinas/metabolismo , Quimiotaxia de Leucócito , Hepacivirus/patogenicidade , Hepatócitos/metabolismo , Hepatócitos/patologia , Hepatócitos/virologia , Interações Hospedeiro-Patógeno , Humanos , Quinase I-kappa B/metabolismo , Imunidade Inata , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/virologia , Fígado/metabolismo , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/patologia , Neoplasias Hepáticas/virologia , Ativação Linfocitária , Linfócitos/virologia , Masculino , Camundongos , Camundongos Transgênicos , NF-kappa B , RNA Polimerase Dependente de RNA/antagonistas & inibidores , Transdução de Sinais , Regulação para Cima , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas não Estruturais Virais/metabolismo , Proteínas Virais/metabolismoRESUMO
BACKGROUND & AIMS: Apicobasal polarity, which is essential for epithelial structure and function, is targeted by several tumour-related pathogens and is generally perturbed in the course of carcinogenesis. Hepatitis C virus (HCV) infection is associated with a strong risk of hepatocellular carcinoma, typically preceded by dysplastic alterations of cell morphology. We investigated the molecular mechanisms and the functional consequences of HCV-driven perturbations of epithelial polarity. METHODS: We used biochemical, genetic, and cell biology approaches to assess the impact of hepatitis C viral protein NS5A on the polarity and function of hepatocytes and hepatic progenitors. Transgenic animals and xenograft models served for in vivo validation of the results obtained in cell culture. RESULTS: We found that expression of HCV-NS5A in primary hepatic precursors and in immortalized hepatocyte cell lines gave rise to profound modifications of cell polarity, leading to epithelial to mesenchymal transition (EMT). NS5A, either alone or in the context of the full complement of viral proteins in the course of infection, acted through activating Twist2, a transcriptional regulator of EMT. The effects of NS5A were additive to those of TGF-ß, a cytokine abundant in diseased liver and highly relevant to HCV-related pathology. Moreover, NS5A cooperates with oncogenic Ras, giving rise to transformed, invasive cells that are highly tumorigenic in vivo. CONCLUSIONS: Our data suggest that in the context of HCV infection, NS5A favors formation of preneoplastic lesions by disrupting cell polarity and additional oncogenic events cooperate with the viral protein to give rise to motile and invasive tumour cells.
Assuntos
Transformação Celular Neoplásica/patologia , Transição Epitelial-Mesenquimal/fisiologia , Hepatite C/complicações , Hepatócitos/patologia , Proteínas não Estruturais Virais/fisiologia , Animais , Animais Geneticamente Modificados , Linhagem Celular , Polaridade Celular/fisiologia , Células Cultivadas , Hepatite C/metabolismo , Hepatite C/patologia , Hepatócitos/metabolismo , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Proteínas Repressoras/fisiologia , Fatores de Risco , Fator de Crescimento Transformador beta/metabolismo , Transplante Heterólogo , Proteína 1 Relacionada a Twist/fisiologiaRESUMO
BACKGROUND & AIMS: Interferon-based therapies for hepatitis C virus (HCV) infection are limited by side effects and incomplete response rates, particularly among transplant recipients. We screened a library of plant-derived small molecules to identify HCV inhibitors with novel mechanisms. METHODS: We isolated phenolic compounds from Marrubium peregrinum L (Lamiaceae). Replication of HCV RNA, virus production, and cell entry were monitored using replicons and infectious HCV. Inhibition of HCV was measured in hepatoma cells and primary human hepatocytes using luciferase reporter gene assays, core enzyme-linked immunosorbent assays, or infectivity titration. We tested the bioavailability of the compound in mice. RESULTS: We identified a flavonoid, ladanein (BJ486K), with unreported antiviral activity and established its oral bioavailability in mice. Natural and synthetic BJ486K inhibited a post-attachment entry step, but not RNA replication or assembly; its inhibitory concentration 50% was 2.5 µm. BJ486K was effective against all major HCV genotypes, including a variant that is resistant to an entry inhibitor; it prevented infection of primary human hepatocytes. Combined administration of BJ486K and cyclosporine A had a synergistic effect in inhibition of HCV infection. CONCLUSIONS: BJ486K has oral bioavailability and interferes with entry of HCV into cultured human hepatocytes. It synergizes with cyclosporine A to inhibit HCV infection. Its inhibitory effects are independent of HCV genotype, including a variant that is resistant to an entry inhibitor against scavenger receptor class B type I. Flavonoid derivatives therefore might be developed as components of combination therapies because they are potent, broadly active inhibitors of HCV entry that could prevent graft reinfection after liver transplantation.