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1.
J Environ Qual ; 52(4): 837-846, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37254884

RESUMO

Denitrification, the anaerobic microbial conversion of nitrate (NO3 - ), a common water pollutant, to nitrogen (N) gases, is often high in the soil of natural wetlands. In areas where natural wetlands have been degraded or destroyed, constructed and restored wetlands have been used to restore ecosystem services like denitrification. Thus, denitrification in restored and constructed wetlands could play an important role in treating anthropogenic N sources such as combined sewer overflow discharges which can be high in NO3 - . In this study, we measured denitrification potential using an anaerobic slurry assay and made a suite of ancillary measurements (soil moisture content, microbial biomass carbon [C] and N content, potential net N mineralization and nitrification, soil inorganic N pools, and soil respiration) in four constructed salt marsh wetlands, and a series of wetland habitat basins in Newtown Creek, NY, an urban superfund site. Samples were also taken from natural salt marshes located at Paerdegat Basin, Jamaica Bay, NY. Our results show that constructed Spartina alterniflora marshes in ultra-urban Newtown Creek support denitrification potential equivalent to rates of natural marshes in Jamaica Bay and reference marshes in other urban estuaries. There were significant positive correlations between microbial biomass C and N content and organic matter content and denitrification potential. Results suggest that constructed wetlands can support wetland vegetation, soils, and microbial life and contribute to N removal under ultra-urban conditions.


Assuntos
Desnitrificação , Recuperação e Remediação Ambiental , Solo , Áreas Alagadas , Ecossistema , Nitrogênio/análise , Solo/química
2.
J Hepatol ; 78(2): 343-355, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36309131

RESUMO

BACKGROUND & AIMS: Despite recent approvals, the response to treatment and prognosis of patients with advanced hepatocellular carcinoma (HCC) remain poor. Claudin-1 (CLDN1) is a membrane protein that is expressed at tight junctions, but it can also be exposed non-junctionally, such as on the basolateral membrane of the human hepatocyte. While CLDN1 within tight junctions is well characterized, the role of non-junctional CLDN1 and its role as a therapeutic target in HCC remains unexplored. METHODS: Using humanized monoclonal antibodies (mAbs) specifically targeting the extracellular loop of human non-junctional CLDN1 and a large series of patient-derived cell-based and animal model systems we aimed to investigate the role of CLDN1 as a therapeutic target for HCC. RESULTS: Targeting non-junctional CLDN1 markedly suppressed tumor growth and invasion in cell line-based models of HCC and patient-derived 3D ex vivo models. Moreover, the robust effect on tumor growth was confirmed in vivo in a large series of cell line-derived xenograft and patient-derived xenograft mouse models. Mechanistic studies, including single-cell RNA sequencing of multicellular patient HCC tumorspheres, suggested that CLDN1 regulates tumor stemness, metabolism, oncogenic signaling and perturbs the tumor immune microenvironment. CONCLUSIONS: Our results provide the rationale for targeting CLDN1 in HCC and pave the way for the clinical development of CLDN1-specific mAbs for the treatment of advanced HCC. IMPACT AND IMPLICATIONS: Hepatocellular carcinoma (HCC) is associated with high mortality and unsatisfactory treatment options. Herein, we identified the cell surface protein Claudin-1 as a treatment target for advanced HCC. Monoclonal antibodies targeting Claudin-1 inhibit tumor growth in patient-derived ex vivo and in vivo models by modulating signaling, cell stemness and the tumor immune microenvironment. Given the differentiated mechanism of action, the identification of Claudin-1 as a novel therapeutic target for HCC provides an opportunity to break the plateau of limited treatment response. The results of this preclinical study pave the way for the clinical development of Claudin-1-specific antibodies for the treatment of advanced HCC. It is therefore of key impact for physicians, scientists and drug developers in the field of liver cancer and gastrointestinal oncology.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Animais , Camundongos , Carcinoma Hepatocelular/genética , Claudina-1/genética , Neoplasias Hepáticas/genética , Carcinógenos , Microambiente Tumoral , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Linhagem Celular Tumoral
3.
Sci Transl Med ; 14(676): eabj4221, 2022 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-36542691

RESUMO

Tissue fibrosis is a key driver of end-stage organ failure and cancer, overall accounting for up to 45% of deaths in developed countries. There is a large unmet medical need for antifibrotic therapies. Claudin-1 (CLDN1) is a member of the tight junction protein family. Although the role of CLDN1 incorporated in tight junctions is well established, the function of nonjunctional CLDN1 (njCLDN1) is largely unknown. Using highly specific monoclonal antibodies targeting a conformation-dependent epitope of exposed njCLDN1, we show in patient-derived liver three-dimensional fibrosis and human liver chimeric mouse models that CLDN1 is a mediator and target for liver fibrosis. Targeting CLDN1 reverted inflammation-induced hepatocyte profibrogenic signaling and cell fate and suppressed the myofibroblast differentiation of hepatic stellate cells. Safety studies of a fully humanized antibody in nonhuman primates did not reveal any serious adverse events even at high steady-state concentrations. Our results provide preclinical proof of concept for CLDN1-specific monoclonal antibodies for the treatment of advanced liver fibrosis and cancer prevention. Antifibrotic effects in lung and kidney fibrosis models further indicate a role of CLDN1 as a therapeutic target for tissue fibrosis across organs. In conclusion, our data pave the way for further therapeutic exploration of CLDN1-targeting therapies for fibrotic diseases in patients.


Assuntos
Anticorpos Monoclonais , Plasticidade Celular , Animais , Camundongos , Humanos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Claudina-1 , Cirrose Hepática/tratamento farmacológico
4.
JCI Insight ; 7(13)2022 07 08.
Artigo em Inglês | MEDLINE | ID: mdl-35801591

RESUMO

Hepatocellular carcinoma (HCC) is a leading cause of death among cirrhotic patients, for which chemopreventive strategies are lacking. Recently, we developed a simple human cell-based system modeling a clinical prognostic liver signature (PLS) predicting liver disease progression and HCC risk. In a previous study, we applied our cell-based system for drug discovery and identified captopril, an approved angiotensin converting enzyme (ACE) inhibitor, as a candidate compound for HCC chemoprevention. Here, we explored ACE as a therapeutic target for HCC chemoprevention. Captopril reduced liver fibrosis and effectively prevented liver disease progression toward HCC development in a diethylnitrosamine (DEN) rat cirrhosis model and a diet-based rat model for nonalcoholic steatohepatitis-induced (NASH-induced) hepatocarcinogenesis. RNA-Seq analysis of cirrhotic rat liver tissues uncovered that captopril suppressed the expression of pathways mediating fibrogenesis, inflammation, and carcinogenesis, including epidermal growth factor receptor (EGFR) signaling. Mechanistic data in liver disease models uncovered a cross-activation of the EGFR pathway by angiotensin. Corroborating the clinical translatability of the approach, captopril significantly reversed the HCC high-risk status of the PLS in liver tissues of patients with advanced fibrosis. Captopril effectively prevents fibrotic liver disease progression toward HCC development in preclinical models and is a generic and safe candidate drug for HCC chemoprevention.


Assuntos
Captopril , Carcinoma Hepatocelular , Neoplasias Hepáticas , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Animais , Captopril/farmacologia , Captopril/uso terapêutico , Carcinogênese , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/prevenção & controle , Quimioprevenção , Progressão da Doença , Receptores ErbB/metabolismo , Cirrose Hepática/prevenção & controle , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/prevenção & controle , Peptidil Dipeptidase A/metabolismo , Ratos , Ativação Transcricional
5.
Nat Commun ; 12(1): 5525, 2021 09 17.
Artigo em Inglês | MEDLINE | ID: mdl-34535664

RESUMO

Chronic liver disease and hepatocellular carcinoma (HCC) are life-threatening diseases with limited treatment options. The lack of clinically relevant/tractable experimental models hampers therapeutic discovery. Here, we develop a simple and robust human liver cell-based system modeling a clinical prognostic liver signature (PLS) predicting long-term liver disease progression toward HCC. Using the PLS as a readout, followed by validation in nonalcoholic steatohepatitis/fibrosis/HCC animal models and patient-derived liver spheroids, we identify nizatidine, a histamine receptor H2 (HRH2) blocker, for treatment of advanced liver disease and HCC chemoprevention. Moreover, perturbation studies combined with single cell RNA-Seq analyses of patient liver tissues uncover hepatocytes and HRH2+, CLEC5Ahigh, MARCOlow liver macrophages as potential nizatidine targets. The PLS model combined with single cell RNA-Seq of patient tissues enables discovery of urgently needed targets and therapeutics for treatment of advanced liver disease and cancer prevention.


Assuntos
Descoberta de Drogas , Fígado/patologia , Modelos Biológicos , Animais , Carcinogênese/patologia , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Quimioprevenção , Estudos de Coortes , AMP Cíclico/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Modelos Animais de Doenças , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HEK293 , Hepacivirus/fisiologia , Hepatite C/genética , Hepatócitos/efeitos dos fármacos , Hepatócitos/metabolismo , Hepatócitos/patologia , Humanos , Vigilância Imunológica/efeitos dos fármacos , Inflamação/patologia , Fígado/efeitos dos fármacos , Fígado/metabolismo , Cirrose Hepática/patologia , Neoplasias Hepáticas/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos/patologia , Masculino , Camundongos Knockout , Nizatidina/farmacologia , Prognóstico , Transdução de Sinais/efeitos dos fármacos , Transcriptoma/genética
6.
Life Sci Alliance ; 4(9)2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34290079

RESUMO

Chronic hepatitis B virus (HBV) infection is a major cause of hepatocellular carcinoma (HCC) world-wide. The molecular mechanisms of viral hepatocarcinogenesis are still partially understood. Here, we applied two complementary single-cell RNA-sequencing protocols to investigate HBV-HCC host cell interactions at the single cell level of patient-derived HCC. Computational analyses revealed a marked HCC heterogeneity with a robust and significant correlation between HBV reads and cancer cell differentiation. Viral reads significantly correlated with the expression of HBV-dependency factors such as HLF in different tumor compartments. Analyses of virus-induced host responses identified previously undiscovered pathways mediating viral carcinogenesis, such as E2F- and MYC targets as well as adipogenesis. Mapping of fused HBV-host cell transcripts allowed the characterization of integration sites in individual cancer cells. Collectively, single-cell RNA-Seq unravels heterogeneity and compartmentalization of both, virus and cancer identifying new candidate pathways for viral hepatocarcinogenesis. The perturbation of pro-carcinogenic gene expression even at low HBV levels highlights the need of HBV cure to eliminate HCC risk.


Assuntos
Carcinoma Hepatocelular/etiologia , Transformação Celular Viral , Vírus da Hepatite B/fisiologia , Hepatite B/complicações , Hepatite B/virologia , Neoplasias Hepáticas/etiologia , Adulto , Idoso , Carcinoma Hepatocelular/mortalidade , Carcinoma Hepatocelular/patologia , Diferenciação Celular , Linhagem Celular Tumoral , Suscetibilidade a Doenças , Feminino , Perfilação da Expressão Gênica , Regulação Viral da Expressão Gênica , Hepatite B Crônica/complicações , Hepatite B Crônica/virologia , Humanos , Neoplasias Hepáticas/mortalidade , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Gradação de Tumores , RNA Viral , Análise de Célula Única/métodos , Transcriptoma , Carga Viral
7.
Mar Pollut Bull ; 161(Pt B): 111629, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33217638

RESUMO

The ribbed mussel has been demonstrated to tolerate high levels of urban pollution and inhabits intertidal regions of the New York City estuary. The ability of this bivalve to filter bacteria raises the question of whether it can remove from the water column the fecal bacteria introduced to urban waterways by septic system leakage or sewer overflow. The study here addresses the hypothesis that ribbed mussel filters bacteria introduced by combined sewer overflow (CSO) discharge. Mussels and water were collected from a highly polluted region of the NYC estuary in order to conduct two sets of five trials for filtration of coliform and coccoid fecal indicator bacteria, respectively, Escherichia coli and Enterococcus species. Mussels and water samples were collected in proximity to a major CSO outfall within 1-2 days of a rainfall event to ensure high baseline values of bacterial contamination for filtration trials. For any given Enterococcus or E. coli trial, equal volume water samples were serially distributed across aerated tanks either containing a mussel or not. Comparison of with-mussel versus no-mussel tank water contamination across pooled trials showed significant (P < 0.05) reduction in water exposed to mussel filtration for both, Enterococcus and E. coli trials. For Enterococcus trials, measures of turbidity (suspended particle density) were taken concurrently with measures of bacterial contamination. Regression of contamination against turbidity, with measures standardized across trials, yielded a significant positive association (n = 50, P < 0.0001) across all tank water with a mussel. Thus, contamination reduction was associated with particle removal by mussel filtration.


Assuntos
Bivalves , Esgotos , Animais , Bactérias , Monitoramento Ambiental , Escherichia coli , Fezes , Microbiologia da Água
8.
Sci Rep ; 10(1): 12767, 2020 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-32728070

RESUMO

Recombinant interferon-α (IFN-α) treatment functionally cures chronic hepatitis B virus (HBV) infection in some individuals and suppresses virus replication in hepatocytes infected in vitro. We studied the antiviral effect of conditioned media (CM) from peripheral blood mononuclear cells (PBMCs) stimulated with agonists of Toll-like receptors (TLRs) 2, 7, 8 and 9. We found that CM from PBMCs stimulated with dual-acting TLR7/8 (R848) and TLR2/7 (CL413) agonists were more potent drivers of inhibition of HBe and HBs antigen secretion from HBV-infected primary human hepatocytes (PHH) than CM from PBMCs stimulated with single-acting TLR7 (CL264) or TLR9 (CpG-B) agonists. Inhibition of HBV in PHH did not correlate with the quantity of PBMC-produced IFN-α, but it was a complex function of multiple secreted cytokines. More importantly, we found that the CM that efficiently inhibited HBV production in freshly isolated PHH via various cytokine repertoires and mechanisms did not reduce covalently closed circular (ccc)DNA levels. We confirmed our data with a cell culture model based on HepG2-NTCP cells and the plasmacytoid dendritic cell line GEN2.2. Collectively, our data show the importance of dual-acting TLR agonists inducing broad cytokine repertoires. The development of poly-specific TLR agonists provides novel opportunities towards functional HBV cure.


Assuntos
Hepatite B Crônica/virologia , Hepatócitos/virologia , Leucócitos Mononucleares/metabolismo , Receptores Toll-Like/agonistas , Replicação Viral/efeitos dos fármacos , Meios de Cultivo Condicionados/farmacologia , Citocinas/metabolismo , DNA Circular/metabolismo , Sistemas de Liberação de Medicamentos , Células Hep G2 , Vírus da Hepatite B/fisiologia , Humanos , Imunidade Inata/efeitos dos fármacos , Interferon-alfa/metabolismo , Receptores Toll-Like/metabolismo
9.
Gut ; 69(2): 380-392, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31076402

RESUMO

OBJECTIVE: Infection of human hepatocytes by the hepatitis C virus (HCV) is a multistep process involving both viral and host factors. microRNAs (miRNAs) are small non-coding RNAs that post-transcriptionally regulate gene expression. Given that miRNAs were indicated to regulate between 30% and 75% of all human genes, we aimed to investigate the functional and regulatory role of miRNAs for the HCV life cycle. DESIGN: To systematically reveal human miRNAs affecting the HCV life cycle, we performed a two-step functional high-throughput miRNA mimic screen in Huh7.5.1 cells infected with recombinant cell culture-derived HCV. miRNA targeting was then assessed using a combination of computational and functional approaches. RESULTS: We uncovered miR-501-3p and miR-619-3p as novel modulators of HCV assembly/release. We discovered that these miRNAs regulate O-linked N-acetylglucosamine (O-GlcNAc) transferase (OGT) protein expression and identified OGT and O-GlcNAcylation as regulators of HCV morphogenesis and infectivity. Furthermore, increased OGT expression in patient-derived liver tissue was associated with HCV-induced liver disease and cancer. CONCLUSION: miR-501-3p and miR-619-3p and their target OGT are previously undiscovered regulatory host factors for HCV assembly and infectivity. In addition to its effect on HCV morphogenesis, OGT may play a role in HCV-induced liver disease and hepatocarcinogenesis.


Assuntos
Hepacivirus/patogenicidade , Hepatite C Crônica/genética , N-Acetilglucosaminiltransferases/fisiologia , Regulação da Expressão Gênica/fisiologia , Técnicas de Silenciamento de Genes/métodos , Estudo de Associação Genômica Ampla/métodos , Hepacivirus/fisiologia , Hepatite C Crônica/virologia , Hepatócitos/virologia , Interações Hospedeiro-Patógeno/genética , Humanos , Estágios do Ciclo de Vida/genética , MicroRNAs/genética , Morfogênese/fisiologia , N-Acetilglucosaminiltransferases/genética , Regulação para Cima , Virulência/genética
10.
Nature ; 572(7768): 199-204, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31292543

RESUMO

The human liver is an essential multifunctional organ. The incidence of liver diseases is rising and there are limited treatment options. However, the cellular composition of the liver remains poorly understood. Here we performed single-cell RNA sequencing of about 10,000 cells from normal liver tissue from nine human donors to construct a human liver cell atlas. Our analysis identified previously unknown subtypes of endothelial cells, Kupffer cells, and hepatocytes, with transcriptome-wide zonation of some of these populations. We show that the EPCAM+ population is heterogeneous, comprising hepatocyte-biased and cholangiocyte populations as well as a TROP2int progenitor population with strong potential to form bipotent liver organoids. As a proof-of-principle, we used our atlas to unravel the phenotypic changes that occur in hepatocellular carcinoma cells and in human hepatocytes and liver endothelial cells engrafted into a mouse liver. Our human liver cell atlas provides a powerful resource to enable the discovery of previously unknown cell types in normal and diseased livers.


Assuntos
Células Epiteliais/citologia , Hepatócitos/citologia , Fígado/citologia , Células-Tronco/citologia , Adulto , Animais , Antígenos de Neoplasias/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/imunologia , Carcinoma Hepatocelular/patologia , Moléculas de Adesão Celular/metabolismo , Quimera/imunologia , Quimera/metabolismo , Células Endoteliais/citologia , Células Endoteliais/imunologia , Células Epiteliais/imunologia , Feminino , Regulação da Expressão Gênica , Hepatócitos/imunologia , Hepatócitos/metabolismo , Humanos , Fígado/imunologia , Masculino , Camundongos , Organoides/metabolismo , RNA Citoplasmático Pequeno/genética , RNA-Seq , Reprodutibilidade dos Testes , Células-Tronco/imunologia
11.
Gastroenterology ; 157(2): 537-551.e9, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30978357

RESUMO

BACKGROUND & AIMS: The mechanisms of hepatitis C virus (HCV) infection, liver disease progression, and hepatocarcinogenesis are only partially understood. We performed genomic, proteomic, and metabolomic analyses of HCV-infected cells and chimeric mice to learn more about these processes. METHODS: Huh7.5.1dif (hepatocyte-like cells) were infected with culture-derived HCV and used in RNA sequencing, proteomic, metabolomic, and integrative genomic analyses. uPA/SCID (urokinase-type plasminogen activator/severe combined immunodeficiency) mice were injected with serum from HCV-infected patients; 8 weeks later, liver tissues were collected and analyzed by RNA sequencing and proteomics. Using differential expression, gene set enrichment analyses, and protein interaction mapping, we identified pathways that changed in response to HCV infection. We validated our findings in studies of liver tissues from 216 patients with HCV infection and early-stage cirrhosis and paired biopsy specimens from 99 patients with hepatocellular carcinoma, including 17 patients with histologic features of steatohepatitis. Cirrhotic liver tissues from patients with HCV infection were classified into 2 groups based on relative peroxisome function; outcomes assessed included Child-Pugh class, development of hepatocellular carcinoma, survival, and steatohepatitis. Hepatocellular carcinomas were classified according to steatohepatitis; the outcome was relative peroxisomal function. RESULTS: We quantified 21,950 messenger RNAs (mRNAs) and 8297 proteins in HCV-infected cells. Upon HCV infection of hepatocyte-like cells and chimeric mice, we observed significant changes in levels of mRNAs and proteins involved in metabolism and hepatocarcinogenesis. HCV infection of hepatocyte-like cells significantly increased levels of the mRNAs, but not proteins, that regulate the innate immune response; we believe this was due to the inhibition of translation in these cells. HCV infection of hepatocyte-like cells increased glucose consumption and metabolism and the STAT3 signaling pathway and reduced peroxisome function. Peroxisomes mediate ß-oxidation of very long-chain fatty acids; we found intracellular accumulation of very long-chain fatty acids in HCV-infected cells, which is also observed in patients with fatty liver disease. Cells in livers from HCV-infected mice had significant reductions in levels of the mRNAs and proteins associated with peroxisome function, indicating perturbation of peroxisomes. We found that defects in peroxisome function were associated with outcomes and features of HCV-associated cirrhosis, fatty liver disease, and hepatocellular carcinoma in patients. CONCLUSIONS: We performed combined transcriptome, proteome, and metabolome analyses of liver tissues from HCV-infected hepatocyte-like cells and HCV-infected mice. We found that HCV infection increases glucose metabolism and the STAT3 signaling pathway and thereby reduces peroxisome function; alterations in the expression levels of peroxisome genes were associated with outcomes of patients with liver diseases. These findings provide insights into liver disease pathogenesis and might be used to identify new therapeutic targets.


Assuntos
Hepacivirus/patogenicidade , Hepatite C Crônica/patologia , Hepatócitos/patologia , Fígado/patologia , Animais , Linhagem Celular Tumoral , Conjuntos de Dados como Assunto , Modelos Animais de Doenças , Perfilação da Expressão Gênica , Glucose/metabolismo , Hepatite C Crônica/metabolismo , Hepatite C Crônica/virologia , Hepatócitos/transplante , Hepatócitos/virologia , Humanos , Fígado/citologia , Fígado/virologia , Metabolômica , Camundongos , Peroxissomos/metabolismo , Peroxissomos/patologia , Proteômica , Fator de Transcrição STAT3/metabolismo , Quimeras de Transplante
12.
Antiviral Res ; 162: 118-129, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30599174

RESUMO

Hepatitis B virus (HBV) envelopes as well as empty subviral particles carry in their lipid membranes the small (S), middle (M), and large (L) surface proteins, collectively known as hepatitis B surface antigen (HBsAg). Due to their common S domain all three proteins share a surface-exposed hydrophilic antigenic loop (AGL) with a complex disulfide bridge-dependent structure. The AGL is critical for HBV infectivity and virion secretion, and thus represents a major target for neutralizing antibodies. Previously, a human monoclonal antibody (mAb) targeting a conformational epitope in the AGL, IgG12, exhibited 1000-fold higher neutralizing activity than hepatitis B immune globulin (HBIG). Here we designed a single-chain variable fragment (scFv) homolog of IgG12, G12-scFv, which could be efficiently produced in soluble form in the cytoplasm of E. coli SHuffle cells. Independent in vitro assays verified specific binding of G12-scFv to a conformational S epitope shared with IgG12. Despite 20-fold lower affinity, G12-scFv but not an irrelevant scFv potently neutralized HBV infection of susceptible hepatoma cells (IC50 = 1.8 nM). Strikingly, low concentrations of G12-scFv blocked virion secretion from HBV producing cells (IC50 = 1.25 nM) without disturbing intracellular viral replication, whereas extracellular HBsAg was reduced only at >100-fold higher though still nontoxic concentration. The inhibitory effects correlated with S binding specificity and presumably also G12-scFv internalization into cells. Together these data suggest G12-scFv as a highly specific yet easily accessible novel tool for basic, diagnostic, and possibly future therapeutic applications.


Assuntos
Antígenos de Superfície da Hepatite B/imunologia , Vírus da Hepatite B/efeitos dos fármacos , Anticorpos de Cadeia Única/imunologia , Anticorpos de Cadeia Única/farmacologia , Vírion/efeitos dos fármacos , Anticorpos Neutralizantes , Escherichia coli , Células Hep G2 , Vírus da Hepatite B/fisiologia , Humanos , Concentração Inibidora 50 , Anticorpos de Cadeia Única/biossíntese , Vírion/fisiologia , Replicação Viral/efeitos dos fármacos
13.
Hepatology ; 68(5): 1695-1709, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-29679386

RESUMO

Chronic hepatitis B virus (HBV) infection is a major cause of chronic liver disease and cancer worldwide. The mechanisms of viral genome sensing and the evasion of innate immune responses by HBV infection are still poorly understood. Recently, the cyclic guanosine monophosphate-adenosine monophosphate synthase (cGAS) was identified as a DNA sensor. In this study, we investigated the functional role of cGAS in sensing HBV infection and elucidate the mechanisms of viral evasion. We performed functional studies including loss-of-function and gain-of-function experiments combined with cGAS effector gene expression profiling in an infectious cell culture model, primary human hepatocytes, and HBV-infected human liver chimeric mice. Here, we show that cGAS is expressed in the human liver, primary human hepatocytes, and human liver chimeric mice. While naked relaxed-circular HBV DNA is sensed in a cGAS-dependent manner in hepatoma cell lines and primary human hepatocytes, host cell recognition of viral nucleic acids is abolished during HBV infection, suggesting escape from sensing, likely during packaging of the genome into the viral capsid. While the hepatocyte cGAS pathway is functionally active, as shown by reduction of viral covalently closed circular DNA levels in gain-of-function studies, HBV infection suppressed cGAS expression and function in cell culture models and humanized mice. Conclusion: HBV exploits multiple strategies to evade sensing and antiviral activity of cGAS and its effector pathways.


Assuntos
Vírus da Hepatite B/patogenicidade , Hepatite B/fisiopatologia , Hepatócitos/virologia , Evasão da Resposta Imune/fisiologia , Nucleotídeos Cíclicos/metabolismo , Animais , Western Blotting , Técnicas de Cultura de Células , DNA Viral/imunologia , Perfilação da Expressão Gênica/métodos , Hepatite B/imunologia , Hepatócitos/metabolismo , Interações Hospedeiro-Patógeno , Humanos , Evasão da Resposta Imune/imunologia , Hibridização in Situ Fluorescente/métodos , Camundongos , Reação em Cadeia da Polimerase em Tempo Real
14.
Gut ; 67(4): 736-745, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-28360099

RESUMO

OBJECTIVE: HCV infection is a leading cause of chronic liver disease and a major indication for liver transplantation. Although direct-acting antivirals (DAAs) have much improved the treatment of chronic HCV infection, alternative strategies are needed for patients with treatment failure. As an essential HCV entry factor, the tight junction protein claudin-1 (CLDN1) is a promising antiviral target. However, genotype-dependent escape via CLDN6 and CLDN9 has been described in some cell lines as a possible limitation facing CLDN1-targeted therapies. Here, we evaluated the clinical potential of therapeutic strategies targeting CLDN1. DESIGN: We generated a humanised anti-CLDN1 monoclonal antibody (mAb) (H3L3) suitable for clinical development and characterised its anti-HCV activity using cell culture models, a large panel of primary human hepatocytes (PHH) from 12 different donors, and human liver chimeric mice. RESULTS: H3L3 pan-genotypically inhibited HCV pseudoparticle entry into PHH, irrespective of donor. Escape was likely precluded by low surface expression of CLDN6 and CLDN9 on PHH. Co-treatment of a panel of PHH with a CLDN6-specific mAb did not enhance the antiviral effect of H3L3, confirming that CLDN6 does not function as an entry factor in PHH from multiple donors. H3L3 also inhibited DAA-resistant strains of HCV and synergised with current DAAs. Finally, H3L3 cured persistent HCV infection in human-liver chimeric uPA-SCID mice in monotherapy. CONCLUSIONS: Overall, these findings underscore the clinical potential of CLDN1-targeted therapies and describe the functional characterisation of a humanised anti-CLDN1 antibody suitable for further clinical development to complement existing therapeutic strategies for HCV.


Assuntos
Anticorpos Monoclonais/farmacologia , Antivirais/farmacologia , Claudina-1/antagonistas & inibidores , Hepacivirus/efeitos dos fármacos , Hepatite C/prevenção & controle , Hepatócitos/efeitos dos fármacos , Fatores Imunológicos/farmacologia , Animais , Claudina-1/imunologia , Hepatite C/imunologia , Hepatócitos/imunologia , Hepatócitos/virologia , Humanos , Camundongos , Camundongos SCID , Resultado do Tratamento
15.
J Virol ; 90(14): 6387-6400, 2016 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-27147737

RESUMO

UNLABELLED: Hepatitis C virus (HCV)-induced chronic liver disease is a leading cause of hepatocellular carcinoma (HCC). However, the molecular mechanisms underlying HCC development following chronic HCV infection remain poorly understood. MicroRNAs (miRNAs) play an important role in homeostasis within the liver, and deregulation of miRNAs has been associated with liver disease, including HCC. While host miRNAs are essential for HCV replication, viral infection in turn appears to induce alterations of intrahepatic miRNA networks. Although the cross talk between HCV and liver cell miRNAs most likely contributes to liver disease pathogenesis, the functional involvement of miRNAs in HCV-driven hepatocyte injury and HCC remains elusive. Here we combined a hepatocyte-like cell-based model system, high-throughput small RNA sequencing, computational analysis, and functional studies to investigate HCV-miRNA interactions that may contribute to liver disease and HCC. Profiling analyses indicated that HCV infection differentially regulated the expression of 72 miRNAs by at least 2-fold, including miRNAs that were previously described to target genes associated with inflammation, fibrosis, and cancer development. Further investigation demonstrated that the miR-146a-5p level was consistently increased in HCV-infected hepatocyte-like cells and primary human hepatocytes, as well as in liver tissue from HCV-infected patients. Genome-wide microarray and computational analyses indicated that miR-146a-5p overexpression modulates pathways that are related to liver disease and HCC development. Furthermore, we showed that miR-146a-5p has a positive impact on late steps of the viral replication cycle, thereby increasing HCV infection. Collectively, our data indicate that the HCV-induced increase in miR-146a-5p expression both promotes viral infection and is relevant for pathogenesis of liver disease. IMPORTANCE: HCV is a leading cause of chronic liver disease and cancer. However, how HCV induces liver cancer remains poorly understood. There is accumulating evidence that a viral cure does not eliminate the risk for HCC development. Thus, there is an unmet medical need to develop novel approaches to predict and prevent virus-induced HCC. miRNA expression is known to be deregulated in liver disease and cancer. Furthermore, miRNAs are essential for HCV replication, and HCV infection alters miRNA expression. However, how miRNAs contribute to HCV-driven pathogenesis remains elusive. Here we show that HCV induces miRNAs that may contribute to liver injury and carcinogenesis. The miR-146a-5p level was consistently increased in different cell-based models of HCV infection and in HCV patient-derived liver tissue. Furthermore, miR-146a-5p increased HCV infection. Collectively, our data are relevant to understanding viral pathogenesis and may open perspectives for novel biomarkers and prevention of virus-induced liver disease and HCC.


Assuntos
Carcinoma Hepatocelular/virologia , Hepacivirus/patogenicidade , Hepatite C/virologia , Hepatócitos/metabolismo , Neoplasias Hepáticas/virologia , Redes e Vias Metabólicas/genética , MicroRNAs/genética , Adulto , Idoso , Biomarcadores/análise , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Feminino , Perfilação da Expressão Gênica , Hepatite C/genética , Hepatite C/patologia , Hepatócitos/citologia , Hepatócitos/virologia , Sequenciamento de Nucleotídeos em Larga Escala , Interações Hospedeiro-Patógeno , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Masculino , Pessoa de Meia-Idade , Ativação Transcricional , Regulação para Cima
16.
Mol Med Rep ; 13(3): 2645-54, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26820174

RESUMO

Adoptive immunotherapy using autologous cytokine-induced killer (CIK) cells reduces the recurrence rate of hepatocellular carcinoma (HCC) in association with transarterial chemoembolization or radiofrequency. However, a large­scale development of this immunotherapy remains difficult to consider in an autologous setting, considering the logistical hurdles associated with the production of this cell therapy product. A previous study has provided the in vitro and in vivo proof­of­concept that allogeneic suicide gene­modified killer cells (aSGMKCs) from healthy blood donors (a cell therapy product previously demonstrated to provide anti­leukemic effects to patients receiving allogeneic hematopoietic transplantation) may exert a potent anti­tumor effect towards HCC. Therefore, the development of a bank of 'ready­for­use' aSGMKCs was proposed as an approach allowing for the development of immunotherapies that are more convenient and on a broader scale than that of autologous therapies. In the present study, aSGMKCs were compared with CIK cells generated according to three different protocols. Similar to CIK cells, the cytotoxic activity of aSGMKCs toward the Huh­7 HCC cell line was mediated by tumor necrosis factor­related apoptosis­inducing ligand, tumor necrosis factor­α and interferon­Î³. Furthermore, the frequency of natural killer (NK), NK­like T and T cells, and their in vitro and in vivo cytotoxicity activities were similar between aSGMKCs and CIK cells. Thus, the present study demonstrated that aSGMKCs are similar to CIK cells, further suggesting the possibility for future use of aSGMKCs in the treatment of solid tumors, including HCC.


Assuntos
Carcinoma Hepatocelular/terapia , Células Matadoras Induzidas por Citocinas/imunologia , Genes Transgênicos Suicidas , Neoplasias Hepáticas/terapia , Animais , Linhagem Celular Tumoral , Células Matadoras Induzidas por Citocinas/transplante , Testes Imunológicos de Citotoxicidade , Feminino , Células HeLa , Humanos , Imunoterapia Adotiva , Masculino , Camundongos , Fenótipo , Transplante Homólogo
17.
Hepatology ; 63(1): 35-48, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26224662

RESUMO

UNLABELLED: Chronic hepatitis B and D infections are major causes of liver disease and hepatocellular carcinoma worldwide. Efficient therapeutic approaches for cure are absent. Sharing the same envelope proteins, hepatitis B virus and hepatitis delta virus use the sodium/taurocholate cotransporting polypeptide (a bile acid transporter) as a receptor to enter hepatocytes. However, the detailed mechanisms of the viral entry process are still poorly understood. Here, we established a high-throughput infectious cell culture model enabling functional genomics of hepatitis delta virus entry and infection. Using a targeted RNA interference entry screen, we identified glypican 5 as a common host cell entry factor for hepatitis B and delta viruses. CONCLUSION: These findings advance our understanding of virus cell entry and open new avenues for curative therapies. As glypicans have been shown to play a role in the control of cell division and growth regulation, virus-glypican 5 interactions may also play a role in the pathogenesis of virus-induced liver disease and cancer.


Assuntos
Glipicanas/fisiologia , Vírus da Hepatite B/patogenicidade , Vírus Delta da Hepatite/patogenicidade , RNA não Traduzido/fisiologia , Internalização do Vírus , Células Cultivadas , Humanos
18.
Hum Gene Ther Methods ; 26(6): 197-210, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26467420

RESUMO

We evaluated the possibility of introducing a combination of six oncogenes into primary porcine hepatocytes (PPH) using a lentiviral vector (LV)-mediated gene transfer in order to develop a porcine hepatocellular carcinoma model based on autologous transplantation of ex vivo-transformed hepatocytes. The six oncogenes were introduced into three plasmids, hence enabling the production of LVs encoding a luciferase reporter gene and hTERT+p53(DD), cyclinD1+CDK4(R24C), and c-myc(T58A)+HRas(G21V) genes, respectively. In order to improve the protection of the laboratory personnel manipulating such LVs, we used a compact cell culture cassette (CliniCell(®) device) as a closed cell culture system. We demonstrated that the CliniCell device allows to produce LVs, through plasmid transfection of 293T cells, and, after transfer to a second cassette, to transduce PPH with a similar efficacy as conventional open cell culture systems such as flasks or Petri dishes. Additionally, it is possible to cryopreserve at -80°C the transduced cells, directly in the CliniCell device used for the transduction. In conclusion, the use of a closed culture system for the safe handling of oncogene-encoding LVs lays the foundation for the development of porcine tumor models based on the autologous transplantation of ex vivo-transformed primary cells.


Assuntos
Técnicas de Cultura Celular por Lotes , Vetores Genéticos/genética , Vetores Genéticos/isolamento & purificação , Lentivirus/genética , Replicação Viral , Animais , Técnicas de Cultura Celular por Lotes/instrumentação , Técnicas de Cultura Celular por Lotes/métodos , Técnicas de Cultura Celular por Lotes/normas , Expressão Gênica , Genes Reporter , Células HEK293 , Hepatócitos , Humanos , Suínos , Transdução Genética , Transgenes
19.
PLoS One ; 10(6): e0118496, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26107173

RESUMO

The ability to imitate complex sounds is rare, and among birds has been found only in parrots, songbirds, and hummingbirds. Parrots exhibit the most advanced vocal mimicry among non-human animals. A few studies have noted differences in connectivity, brain position and shape in the vocal learning systems of parrots relative to songbirds and hummingbirds. However, only one parrot species, the budgerigar, has been examined and no differences in the presence of song system structures were found with other avian vocal learners. Motivated by questions of whether there are important differences in the vocal systems of parrots relative to other vocal learners, we used specialized constitutive gene expression, singing-driven gene expression, and neural connectivity tracing experiments to further characterize the song system of budgerigars and/or other parrots. We found that the parrot brain uniquely contains a song system within a song system. The parrot "core" song system is similar to the song systems of songbirds and hummingbirds, whereas the "shell" song system is unique to parrots. The core with only rudimentary shell regions were found in the New Zealand kea, representing one of the only living species at a basal divergence with all other parrots, implying that parrots evolved vocal learning systems at least 29 million years ago. Relative size differences in the core and shell regions occur among species, which we suggest could be related to species differences in vocal and cognitive abilities.


Assuntos
Encéfalo/fisiologia , Papagaios/fisiologia , Vocalização Animal/fisiologia , Animais , Humanos , Aprendizagem , Música , Nova Zelândia
20.
J Exp Med ; 211(5): 857-68, 2014 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-24752298

RESUMO

The molecular mechanisms that link IFN-λ3 genotypes to differential induction of interferon (IFN)-stimulated genes (ISGs) in the liver of patients with chronic hepatitis C (CHC) are not known. We measured the expression of IFN-λ and of the specific IFN-λ receptor chain (IFN-λR1) in 122 liver biopsies of patients with CHC and 53 control samples. The IFN-λ3 genotype was not associated with differential expression of IFN-λ, but rather IFN-λR1. In a series of 30 primary human hepatocyte (PHH) samples, IFN-λR1 expression was low but could be induced with IFN-α. IFN-α-induced IFN-λR1 expression was significantly stronger in PHHs carrying the minor IFN-λ3 allele. The analysis of liver biopsies of patients with CHC revealed a strong association of high IFN-λR1 expression with elevated ISG expression, with IFN-λ3 minor alleles, and with nonresponse to pegylated IFN-α and ribavirin. The findings provide a missing link between the IFN-λ3 genotype and the associated phenotype of treatment nonresponse.


Assuntos
Hepatite C Crônica/metabolismo , Interferons/metabolismo , Fígado/metabolismo , Receptores de Interferon/metabolismo , Biópsia , Western Blotting , Estudos de Casos e Controles , Primers do DNA/genética , Imunofluorescência , Genótipo , Humanos , Hibridização in Situ Fluorescente , Interferon-alfa/uso terapêutico , Microscopia Confocal , Polimorfismo de Nucleotídeo Único/genética , Reação em Cadeia da Polimerase em Tempo Real , Suíça
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