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1.
Clin Res Hepatol Gastroenterol ; 42(4): 313-318, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29551607

RESUMO

INTRODUCTION: Presence of anti-E1E2 antibodies was previously associated with spontaneous cure of hepatitis C virus (HCV) and predictive before treatment of a sustained virological response (SVR) to bi- or tri-therapy in naïve or experienced patients, regardless of HCV genotype. We investigated the impact of anti-E1E2 seroprevalence at baseline on treatment response in patients receiving direct-acting antiviral (DAA) therapy. MATERIAL AND METHODS: We screened anti-E1E2 antibodies by ELISA in serum samples collected at treatment initiation for two groups of patients: 59 with SVR at the end of DAA treatment and 44 relapsers after DAA treatment. Nineteen patients received a combination of ribavirin (RBV) or PEG-interferon/ribavirin with sofosbuvir or daclatasvir and others received interferon-free treatment with DAA±RBV. HCV viral load was measured at different time points during treatment in a subgroup of patients. RESULTS: A significant association was observed between presence of anti-E1E2 and HCV viral load<6log10 prior treatment. Among patients with anti-E1E2 at baseline, 70% achieved SVR whereas among patients without anti-E1E2, only 45% achieved SVR. Conversely, 66% of patients experiencing DAA-failure were anti-E1E2 negative at baseline. In the multivariate analysis, presence of anti-E1E2 was significantly associated with SVR after adjustment on potential cofounders such as age, sex, fibrosis stage, prior HCV treatment and alanine aminotransferase (ALT) level. CONCLUSIONS: The presence of anti-E1E2 at treatment initiation is a predictive factor of SVR among patients treated with DAA and more likely among patients with low initial HCV viral load (<6log10). Absence of anti-E1E2 at baseline could predict DAA-treatment failure.


Assuntos
Anticorpos/sangue , Antivirais/uso terapêutico , Hepatite C Crônica/tratamento farmacológico , Peptídeos/imunologia , Idoso , Biomarcadores/sangue , Carbamatos , Quimioterapia Combinada , Ensaio de Imunoadsorção Enzimática , Feminino , Hepacivirus/fisiologia , Hepatite C Crônica/virologia , Humanos , Imidazóis/uso terapêutico , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis/uso terapêutico , Pirrolidinas , Proteínas Recombinantes/uso terapêutico , Estudos Retrospectivos , Ribavirina/uso terapêutico , Estudos Soroepidemiológicos , Sofosbuvir/uso terapêutico , Valina/análogos & derivados , Carga Viral/efeitos dos fármacos
2.
PLoS One ; 12(6): e0179697, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28636622

RESUMO

Hepatitis B virus (HBV) infection remains a major public health concern worldwide with 240 million individuals chronically infected and at risk of developing cirrhosis and hepatocellular carcinoma. Current treatments rarely cure chronic hepatitis B infection, highlighting the need for new anti-HBV drugs. Nucleic acid polymers (NAPs) are phosphorothioated oligonucleotides that have demonstrated a great potential to inhibit infection with several viruses. In chronically infected human patients, NAPs administration lead to a decline of blood HBsAg and HBV DNA and to HBsAg seroconversion, the expected signs of functional cure. NAPs have also been shown to prevent infection of duck hepatocytes with the Avihepadnavirus duck hepatitis B virus (DHBV) and to exert an antiviral activity against established DHBV infection in vitro and in vivo. In this study, we investigated the specific anti-HBV antiviral activity of NAPs in the HepaRG human hepatoma cell line and primary cultures of human hepatocytes. NAPs with different chemical features (phosphorothioation, 2'O-methyl ribose, 5-methylcytidine) were assessed for antiviral activity when provided at the time of HBV inoculation or post-inoculation. NAPs dose-dependently inhibited HBV entry in a phosphorothioation-dependent, sequence-independent and size-dependent manner. This inhibition of HBV entry by NAPs was impaired by 2'O-methyl ribose modification. NAP treatment after viral inoculation did not elicit any antiviral activity.


Assuntos
Antivirais/farmacologia , Vírus da Hepatite B/fisiologia , Ácidos Nucleicos/química , Polímeros/farmacologia , Internalização do Vírus/efeitos dos fármacos , Antivirais/química , Antivirais/toxicidade , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Citidina/análogos & derivados , Citidina/química , DNA Viral/sangue , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Vírus da Hepatite B/genética , Hepatócitos/citologia , Hepatócitos/virologia , Humanos , Imunoensaio , Fosfatos/química , Polímeros/química , Polímeros/toxicidade , Reação em Cadeia da Polimerase em Tempo Real
3.
J Hepatol ; 66(5): 897-909, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28043874

RESUMO

BACKGROUND & AIMS: Hepatitis B virus (HBV) persistence and the pathobiology of chronic HBV (CHB) infections result from the interplay between viral replication and host immune responses. We aimed to comprehensively analyse the expression of intrahepatic host genes as well as serum and liver HBV markers in a large cohort of untreated CHB patients. METHODS: One-hundred and five CHB patients untreated at the time of liver biopsy (34 HBeAg[+] and 71 HBeAg[-]) were analysed for the intrahepatic expression profile of 67 genes belonging to multiple innate immunity pathways. Results were correlated to serological (quantification of HBsAg [qHBsAg] and HBV DNA) and intrahepatic viral markers (total HBV DNA, pre-genomic RNA and covalently closed circular HBV DNA). RESULTS: Intrahepatic gene expression profiling revealed a strong downregulation of antiviral effectors, interferon stimulated genes, Toll-like and pathogen recognition receptor pathways in CHB patients as compared to non-infected controls, which was not directly correlated to HBV replication. A subset of genes [CXCL10, GBP1, IFITM1, IFNB1, IL10, IL6, ISG15, TLR3, SOCS1, SOCS3] was more repressed in HBeAg(-) respect to HBeAg(+) patients (median of serum HBV DNA 7.9×103vs. 7.9×107IU/ml, respectively). Notably, HBeAg(-) patients with lower qHBsAg (<5×103IU/ml) showed a relief of repression of genes belonging to multiple pathways. CONCLUSIONS: Our results show a strong impairment of innate immune responses in the liver of CHB patients. The association of low levels of qHBsAg with gene repression, if confirmed, might prove useful for the identification of patients who would most benefit from immune-modulators and/or HBsAg targeting agents as strategies to restore immune responsiveness. LAY SUMMARY: Chronic hepatitis B virus (HBV) infections represent a major public health problem worldwide. Over 200 million people are chronically infected and at risk of developing chronic hepatitis, liver cirrhosis and cancer. Our work aimed to understand the molecular consequences of chronic hepatitis B in the infected liver. It was conducted in a large cohort of untreated chronically infected HBV patients and analysed the expression of immunity and liver disease-related genes in the liver, with respect to markers of viral replication and persistence. Our results indicate that chronic HBV infection has a suppressive effect on immune responses, which was more pronounced with high levels of hepatitis B virus surface antigen (HBsAg). These data provide novel insight into the mechanisms of HBV persistence in the liver and suggest that approaches aimed at reducing HBsAg levels, may restore immune responsiveness against the virus.


Assuntos
Hepatite B Crônica/imunologia , Fígado/imunologia , Adulto , Regulação para Baixo , Feminino , Antígenos de Superfície da Hepatite B/análise , Antígenos E da Hepatite B/análise , Hepatite B Crônica/patologia , Humanos , Imunidade Inata , Masculino , Pessoa de Meia-Idade , Transcriptoma
4.
Clin Res Hepatol Gastroenterol ; 39(6): 699-704, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25900002

RESUMO

BACKGROUND AND AIMS: We previously showed that pre-treatment serum anti-E1E2 predicted hepatitis C virus (HCV) RNA viral kinetics (VKs) and treatment outcome in patients with chronic hepatitis C receiving pegylated interferon/ribavirin (Peg-IFN/RBV) double therapy. Here, we determined whether baseline anti-E1E2 was correlated with the on-treatment VK and could predict virological outcome in treatment-experienced HCV-infected cirrhotic patients receiving protease inhibitor-based triple therapy. METHODS: Sera from 19 patients with HCV genotype 1 infection and compensated cirrhosis who failed to respond to a prior course of Peg-IFN/RBV were selected at time 0 before starting triple therapy with boceprevir or telaprevir. We assessed patients with sustained viral response 12 weeks after the end of triple therapy (SVR12) by analyzing VKs at weeks 4, 12, 24, 36, 48 (end of treatment) and 60. RESULTS: Patients baseline characteristics were similar to the well-defined CUPIC cohort (age, HCV subtype, baseline viremia, and treatment history). Among the 19 patients, 11 achieved an SVR12. Fifteen patients were positive for pre-treatment anti-E1E2 and all of them achieved SVR12. Moreover, anti-E1E2 and SVR12 correlated with prior response to IFN/RBV therapy (relapse, partial or null response). CONCLUSIONS: Baseline anti-E1E2 could be considered as a new biomarker to predict SVR12 after triple therapy in this most difficult-to-treat population. These results warrant further validation on larger cohorts including patients receiving highly effective direct-acting antivirals to explore whether this test could help in better defining treatment duration for these very costly molecules.


Assuntos
Anticorpos/sangue , Antivirais/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Cirrose Hepática/sangue , Peptídeos/imunologia , Adulto , Idoso , Quimioterapia Combinada , Feminino , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática/complicações , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Valor Preditivo dos Testes , Resultado do Tratamento
5.
J Nutr ; 142(1): 125-30, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22131553

RESUMO

Taste is involved in food preference and choice, and it is thought that it can modulate appetite and food intake. The present study investigated the effect of savory or sweet taste on satiation, reward, and food intake and according to individual differences in eating behavior traits underlying susceptibility to overeating. In a crossover design, 30 women (BMI = 22.7 ± 2.3; age = 21.9 ± 2.6 y) consumed a fixed energy preload (360 kJ/g) with a savory, sweet, or bland taste before selecting and consuming items from a test meal ad libitum. Sensations of hunger were used to calculate the satiating efficiency of the preloads. A computerized task was used to examine effects on food reward (explicit liking and implicit wanting). The Three Factor Eating Questionnaire was used to compare individual differences in eating behavior traits. Satiation and total food intake did not differ according to preload taste, but there was an effect on explicit liking and food selection. The savory preload reduced liking and intake of high-fat savory foods compared to sweet or bland preloads. The eating behavior trait disinhibition interacted with preload taste to determine test meal intake. Higher scores were associated with increased food intake after the sweet preload compared to the savory preload. Independent of preload taste, disinhibition was associated with lower satiating efficiency of the preloads and enhanced implicit wanting for high-fat sweet food. Savory taste has a stronger modulating effect on food preference than sweet or bland taste and may help to preserve normal appetite regulation in people who are susceptible to overeating.


Assuntos
Bebidas , Ingestão de Energia , Hiperfagia , Motivação , Saciação/fisiologia , Adulto , Estudos Cross-Over , Feminino , Humanos
6.
Hepatology ; 54(2): 406-17, 2011 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-21520209

RESUMO

UNLABELLED: HepaRG human liver progenitor cells exhibit morphology and functionality of adult hepatocytes. We investigated the susceptibility of HepaRG hepatocytes to in vitro infection with serum-derived hepatitis C virus (HCV) particles (HCVsp) and the potential neutralizing activity of the E1E2-specific monoclonal antibody (mAb) D32.10. The infection was performed using HCVsp when the cells actively divided at day 3 postplating. HCV RNA, E1E2, and core antigens were quantified in HCV particles recovered from culture supernatants of differentiated cells for up to 66 days. The density distributions of particles were analyzed on iodixanol or sucrose gradients. Electron microscopy (EM) and immune-EM studies were performed for ultrastructural analysis of cells and localization of HCV E1E2 proteins in thin sections. HCV infection of HepaRG cells was documented by increasing production of E1E2-core-RNA(+) HCV particles from day 21 to day 63. Infectious particles sedimented between 1.06 and 1.12 g/mL in iodixanol gradients. E1E2 and core antigens were expressed in 50% of HCV-infected cells at day 31. The D32.10 mAb strongly inhibited HCV RNA production in HepaRG culture supernatants. Infected HepaRG cells frozen at day 56 were reseeded at low density. After only 1-3 subcultures and induction of a cell differentiation process the HepaRG cells produced high titer HCV RNA and thus showed to be sustainably infected. Apolipoprotein B-associated empty E1E2 and complete HCV particles were secreted. Characteristic virus-induced intracellular membrane changes and E1E2 protein-association to vesicles were observed. CONCLUSION: HepaRG progenitor cells permit HCVsp infection. Differentiated HepaRG cells support long-term production of infectious lipoprotein-associated enveloped HCV particles. The E1E2-specific D32.10 mAb neutralizes the infection and this cellular model could be used as a surrogate infection system for the screening of entry inhibitors.


Assuntos
Hepacivirus/patogenicidade , Hepatite C/sangue , Hepatite C/virologia , Hepatócitos/virologia , Proteínas do Envelope Viral/biossíntese , Diferenciação Celular , Células Cultivadas , Humanos , Células-Tronco , Fatores de Tempo , Vírion
7.
Hepatology ; 52(5): 1531-42, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20890942

RESUMO

UNLABELLED: The monoclonal antibody (mAb) D32.10 recognizes a discontinuous epitope encompassing three regions E1 (amino acids 297-306), E2A (amino acids 480-494), and E2B (amino acids 613-621) juxtaposed on the surface of serum-derived hepatitis C virus (HCV) particles (HCVsp). The mAb D32.10 inhibits efficiently and specifically the binding of HCVsp to human hepatocytes. Therefore, we investigated the clinical relevance of anti-E1E2A,B response in the serum of patients infected with HCV. To this end, an enzyme-linked immunosorbent assay (ELISA) using synthetic E1-, E2A-, and E2B-derived peptides was used. The ELISA was validated in terms of sensitivity, specificity, and test efficiency. The detection of the anti-E1E2 D32.10 epitope-binding antibodies during natural HCV infection in more than 300 HCV-positive sera demonstrated significantly (P < 0.001) higher prevalence of these antibodies: (1) in patients who spontaneously cured HCV infection (46 of 52, 88.5%) showing high titers (70% ≥ 1/1000) compared to never-treated patients with chronic hepatitis C (7 of 50, 14%) who actively replicated the virus, and (2) in complete responders (20 of 52, 38.5%) who cleared virus following treatment and achieved a sustained viral response compared to nonresponders (4 of 40, 10%). Serum anti-E1E2 antibodies were monitored before, during, and after the current standard-of-care therapy (pegylated interferon plus ribavirin) in responder and nonresponder patients. Optimal cutoff values were assessed by receiver operating characteristic curve analysis. One month prior to therapy initiation, the threshold of 1131 (optical density × 1000) gave 100% and 86% positive and negative predictive values, respectively, for achieving or not achieving a sustained viral response. CONCLUSION: The anti-E1E2 D32.10 epitope-binding antibodies are associated with control of HCV infection and may represent a new relevant prognostic marker in serum. This unique D32.10 mAb may also have immunotherapeutic potential.


Assuntos
Anticorpos Anti-Idiotípicos/uso terapêutico , Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Anticorpos Anti-Idiotípicos/imunologia , Anticorpos Monoclonais/uso terapêutico , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/uso terapêutico , Epitopos/imunologia , Epitopos/uso terapêutico , Seguimentos , Hepacivirus/imunologia , Hepatite C/sangue , Hepatite C/imunologia , Humanos , Imunoglobulinas/sangue , Estudos Longitudinais , Peptídeos/imunologia , Reprodutibilidade dos Testes , Estudos Soroepidemiológicos , Resultado do Tratamento
8.
Oncogene ; 22(18): 2762-71, 2003 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-12743599

RESUMO

The role of interferon-alpha (IFN-alpha) remains unclear in prevention of virus-induced hepatocellular carcinoma in humans. We have investigated it herewith in the X/myc transgenic mouse model of Hepadnavirus-related hepatocarcinogenesis because of upregulation of c-myc oncogene in the liver. We have demonstrated that IFN-alpha can downregulate dose-dependently hepatocyte proliferation and c-myc overexpression at early premalignant stages, while it does not affect either hepatocyte apoptosis or telomerase activity at these steps. However, continuous and long-term administration of IFN-alpha dose-dependently delays tumor onset in dysplastic livers and increases overall survival of animals, more efficiently whether started before the onset of dysplasia. The present study therefore highlights that early preventive administration of IFN-alpha can slow down evolution towards hepatocellular carcinoma via repression of c-myc and hepatocyte proliferation at premalignant steps in experimental c-myc-induced hepatocarcinogenesis. However, the transient effect observed in this study emphasizes a need to clarify the possible mechanisms of acquired resistance and subsequent therapeutic escape. Our experimental model may be a pertinent tool to explore antioncogenic properties of IFN-alpha in human cirrhotic livers showing c-myc upregulation.


Assuntos
Carcinoma Hepatocelular/prevenção & controle , Carcinoma Hepatocelular/virologia , Genes myc , Infecções por Hepadnaviridae/complicações , Interferon-alfa/uso terapêutico , Neoplasias Hepáticas/prevenção & controle , Neoplasias Hepáticas/virologia , Animais , Antivirais , Apoptose , Sequência de Bases , Carcinoma Hepatocelular/genética , Primers do DNA , Feminino , Hepadnaviridae/isolamento & purificação , Infecções por Hepadnaviridae/prevenção & controle , Hepatócitos/patologia , Fígado/patologia , Fígado/virologia , Neoplasias Hepáticas/genética , Camundongos , Camundongos Transgênicos , Reação em Cadeia da Polimerase Via Transcriptase Reversa
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