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1.
Clin Infect Dis ; 77(Suppl 3): S245-S256, 2023 08 14.
Artigo em Inglês | MEDLINE | ID: mdl-37579210

RESUMO

In a hepatitis C virus (HCV)-controlled human infection model (CHIM), healthy volunteers are inoculated with HCV and then treated. Residual hepatocellular carcinoma (HCC) risk after viral clearance is an important consideration when evaluating the CHIM. We estimate HCC risk in spontaneously cleared HCV and in noncirrhosis after sustained virological response (SVR) to HCV treatment in a systematic review and using data from 3 cohorts: German anti-D, Taiwan, and US Veterans Affairs (VA). For noncirrhosis SVR, the overall HCC rate is 0.33 per 100 patient-years in meta-analysis. HCC rates for the German, Taiwan, and US Veterans Affairs cohorts are 0, 0.14, and 0.02 per 100 patient-years, respectively. Past hepatitis B virus exposure was not accounted for in the Taiwan cohort, while VA patients were likely tested based on liver disease/risk factors, which may confound HCC outcomes. The German cohort with no HCC after 44 years is most comparable to the CHIM participants. Although it is difficult to precisely estimate HCC risk from an HCV CHIM, the data suggest the risk to be very low or negligible.


Assuntos
Carcinoma Hepatocelular , Hepatite C Crônica , Hepatite C , Neoplasias Hepáticas , Humanos , Antivirais/uso terapêutico , Carcinoma Hepatocelular/epidemiologia , Hepacivirus , Hepatite C/complicações , Hepatite C/tratamento farmacológico , Hepatite C/epidemiologia , Hepatite C Crônica/complicações , Hepatite C Crônica/tratamento farmacológico , Neoplasias Hepáticas/epidemiologia , Resposta Viral Sustentada
2.
Gut ; 66(10): 1829-1837, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-27196570

RESUMO

OBJECTIVE: As pathogen sensors, Toll-like receptors (TLR) play a role in the first defence line during HCV infection. However, the impact of the DNA sensor TLR9 on the natural course of HCV infection is unknown. To address this, TLR9 promoter polymorphisms (single nucleotide polymorphisms (SNPs)) rs187084 and rs5743836 were investigated for their effect on disease progression. DESIGN: Therefore, the TLR9 SNPs and the interferon lambda 4 (IFNL4) rs12979860 were genotyped in chronically HCV type 1 infected (n=333), in patients who spontaneously cleared the infection (n=161), in the Swiss HCV cohort (n=1057) and the well-characterised German (n=305) and Irish (n=198) 'anti-D' cohorts. Functional analyses were done with promoter reporter constructs of human TLR9 in B cells and assessing TLR9 mRNA levels in whole blood of healthy volunteers. RESULTS: The TLR9 rs187084 C allele was associated with spontaneous virus clearance in women of the study cohort (OR=2.15 (95% CI 1.18 to 3.90) p=0.012), of the Swiss HCV cohort (OR=2.06 (95% CI 1.02 to 4.18) p=0.044) and in both 'anti-D' cohorts (German: OR=2.01 (95% CI 1.14 to 3.55) p=0.016; Irish: OR=1.93 (95% CI 1.10 to 3.68) p=0.047). Multivariate analysis in the combined study and Swiss HCV cohorts supported the results (OR=1.99 (95% CI 1.30 to 3.05) p=0.002). Functional analyses revealed higher transcriptional activities for both TLR9 variants and an association of the C allele of rs5743836 with allele-specific TLR9 mRNA regulation by oestrogens in women. CONCLUSIONS: TLR9 promoter SNPs are associated with the natural course of HCV infection and show higher transcriptional activities. Our results imply the DNA sensor TLR9 in natural immunity against the RNA virus, HCV.


Assuntos
Hepatite C Crônica/genética , Interleucinas/genética , RNA Mensageiro/sangue , Receptor Toll-Like 9/genética , Adulto , Idoso , Alelos , Progressão da Doença , Feminino , Regulação da Expressão Gênica/genética , Alemanha , Haplótipos , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas , Remissão Espontânea , Estudos Retrospectivos , Fatores Sexuais , Suíça , Transcrição Gênica
3.
Dig Dis Sci ; 61(10): 3061-3071, 2016 10.
Artigo em Inglês | MEDLINE | ID: mdl-26576555

RESUMO

BACKGROUND AND AIMS: Multiple clinical trials have demonstrated the efficacy and safety of tenofovir disoproxil fumarate (TDF) in chronic hepatitis B (CHB). However, long-term efficacy and safety data for TDF in real-life clinical practice are limited. METHODS: Prospective German field practice study in CHB-mono-infected patients. Patients were TDF-naïve but could have been treated previously with other HBV antivirals. RESULTS: Efficacy analysis included 400 patients; 301 (75 %) completed 36 months of TDF treatment. Both treatment-naïve and treatment-experienced patients showed a rapid decline in HBV DNA within 3 months of TDF initiation. After 36 months, HBV DNA < 69 IU/mL was achieved by 91 % of treatment-naïve patients (90 and 92 % in hepatitis B "e" antigen [HBeAg]-positive and [HBeAg]-negative, respectively) and 96 % of treatment-experienced patients (93 and 97 %, respectively). Three patients experienced virologic breakthrough, all with reported non-compliance. Overall, 5.7 % HBeAg-positive and 2.2 % HBeAg-negative patients lost hepatitis B surface antigen. Safety data were consistent with the known TDF safety profile; the most commonly reported adverse events possibly related to TDF were fatigue (2.0 %) and headache (2.0 %). Few patients (1.3 %) experienced renal-related adverse reactions. Creatinine clearance remained relatively stable over time; patients responded favorably where TDF was dose adjusted per label for decreased creatinine clearance. CONCLUSIONS: TDF showed a favorable tolerability profile and induced rapid and sustained suppression of HBV DNA in patients with CHB treated for up to 3 years in routine clinical practice, irrespective of treatment history. Efficacy and safety in this heterogeneous patient population were consistent with data from clinical trials.


Assuntos
Antivirais/uso terapêutico , Hepatite B Crônica/tratamento farmacológico , Tenofovir/uso terapêutico , Adulto , Creatinina/sangue , DNA Viral/sangue , Técnicas de Imagem por Elasticidade , Fadiga/induzido quimicamente , Feminino , Alemanha , Cefaleia/induzido quimicamente , Antígenos de Superfície da Hepatite B/sangue , Antígenos E da Hepatite B/sangue , Hepatite B Crônica/sangue , Hepatite B Crônica/complicações , Hepatite B Crônica/diagnóstico por imagem , Humanos , Nefropatias/sangue , Nefropatias/induzido quimicamente , Fígado/diagnóstico por imagem , Cirrose Hepática/diagnóstico por imagem , Cirrose Hepática/etiologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Carga Viral
4.
Hepatology ; 62(5): 1375-87, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26250868

RESUMO

UNLABELLED: Patients carrying very rare loss-of-function mutations in interleukin-1 receptor-associated kinase 4 (IRAK4), a critical signaling mediator in Toll-like receptor signaling, are severely immunodeficient, highlighting the paramount role of IRAK kinases in innate immunity. We discovered a comparatively frequent coding variant of the enigmatic human IRAK2, L392V (rs3844283), which is found homozygously in ∼15% of Caucasians, to be associated with a reduced ability to induce interferon-alpha in primary human plasmacytoid dendritic cells in response to hepatitis C virus (HCV). Cytokine production in response to purified Toll-like receptor agonists was also impaired. Additionally, rs3844283 was epidemiologically associated with a chronic course of HCV infection in two independent HCV cohorts and emerged as an independent predictor of chronic HCV disease. Mechanistically, IRAK2 L392V showed intact binding to, but impaired ubiquitination of, tumor necrosis factor receptor-associated factor 6, a vital step in signal transduction. CONCLUSION: Our study highlights IRAK2 and its genetic variants as critical factors and potentially novel biomarkers for human antiviral innate immunity.


Assuntos
Hepatite C Crônica/imunologia , Quinases Associadas a Receptores de Interleucina-1/genética , Genótipo , Células HEK293 , Humanos , Interferon-alfa/biossíntese , Interferons , Quinases Associadas a Receptores de Interleucina-1/fisiologia , Interleucinas/genética , Polimorfismo de Nucleotídeo Único , Fator 6 Associado a Receptor de TNF/metabolismo , Receptores Toll-Like/fisiologia , Ubiquitinação
5.
Hepatology ; 60(4): 1449-50, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24890461
6.
PLoS One ; 9(3): e91987, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24637477

RESUMO

INTRODUCTION: Non-invasive assessment of steatosis and fibrosis is of growing relevance in non-alcoholic fatty liver disease (NAFLD). 1H-Magnetic resonance spectroscopy (1H-MRS) and the ultrasound-based controlled attenuation parameter (CAP) correlate with biopsy proven steatosis, but have not been correlated with each other so far. We therefore performed a head-to-head comparison between both methods. METHODS: Fifty patients with biopsy-proven NAFLD and 15 healthy volunteers were evaluated with 1H-MRS and transient elastography (TE) including CAP. Steatosis was defined according to the percentage of affected hepatocytes: S1 5-33%, S2 34-66%, S3 ≥67%. RESULTS: Steatosis grade in patients with NAFLD was S1 36%, S2 40% and S3 24%. CAP and 1H-MRS significantly correlated with histopathology and showed comparable accuracy for the detection of hepatic steatosis: areas under the receiver-operating characteristics curves were 0.93 vs. 0.88 for steatosis ≥S1 and 0.94 vs. 0.88 for ≥S2, respectively. Boot-strapping analysis revealed a CAP cut-off of 300 dB/m for detection of S2-3 steatosis, while retaining the lower cut-off of 215 dB/m for the definition of healthy individuals. Direct comparison between CAP and 1H-MRS revealed only modest correlation (total cohort: r = 0.63 [0.44, 0.76]; NAFLD cases: r = 0.56 [0.32, 0.74]). For detection of F2-4 fibrosis TE had sensitivity and specificity of 100% and 98.1% at a cut-off value of 8.85 kPa. CONCLUSION: Our data suggest a comparable diagnostic value of CAP and 1H-MRS for hepatic steatosis quantification. Combined with the simultaneous TE fibrosis assessment, CAP represents an efficient method for non-invasive characterization of NAFLD. Limited correlation between CAP and 1H-MRS may be explained by different technical aspects, anthropometry, and presence of advanced liver fibrosis.


Assuntos
Técnicas de Imagem por Elasticidade , Espectroscopia de Ressonância Magnética/métodos , Hepatopatia Gordurosa não Alcoólica/diagnóstico , Adulto , Idoso , Biópsia , Estudos de Casos e Controles , Comorbidade , Feminino , Humanos , Fígado/metabolismo , Fígado/patologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
7.
Virol J ; 11: 50, 2014 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-24628791

RESUMO

BACKGROUND: No information is available on the possible influence of the genetic heterogeneity of major hepatitis C virus (HCV) cell receptors on selection of virus variants. FINDINGS: Anti-D globulin preparations contaminated with the HCV strain AD78 caused hepatitis C infection in more than 3000 women in East Germany in 1978. Analysis of the core to NS2 gene sequences of this strain in several globulin batches revealed the presence of three closely related but distinct virus variants of the same strain. Apparently even distribution of these three virus variants was observed in 91 patients infected with the AD78 strain. None of these patients was infected with more than one virus variant, suggesting a selection mechanism of a particular virus variant in each patient. To verify the hypothesis that heterogeneity of HCV cell receptors might influence the virus variant selection, single-nucleotide polymorphisms (SNPs) in low-density lipoprotein receptor (LDLR), occludin (OCLN), and scavenger receptor B1 (SCARB1) genes in AD patients were analyzed. No evident correlation between receptor polymorphisms and presence of a particular virus variant was noted. CONCLUSION: SNPs of HCV cell entry receptors have no influence on virus selection in patients infected with an inoculum containing different virus variants.


Assuntos
Heterogeneidade Genética , Hepacivirus/fisiologia , Receptores Virais/genética , Internalização do Vírus , Feminino , Alemanha Oriental , Humanos , Ocludina/genética , Polimorfismo de Nucleotídeo Único , Receptores de LDL/genética , Receptores Depuradores Classe B/genética , Seleção Genética
8.
Hepatology ; 59(1): 49-57, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23929603

RESUMO

UNLABELLED: The natural course of HCV infection remains controversial. The German HCV (1b)-contaminated anti-D cohort provides an ideal population to investigate the natural course of HCV infection in a large, homogenous cohort of young women from the date of HCV inoculation. Our previous follow-up studies at 20 and 25 years after infection suggested slow fibrosis progression rates in this unique cohort. The aim of our prospective, community-based, multicenter study was to reevaluate the liver disease progression in 718 patients of the original anti-D cohort at 35 years after infection. Patients with self-limited HCV infection (n = 189) were compared to those who failed to eliminate the virus spontaneously (n = 529), comprising patients who were treatment naïve (n = 197) or achieved a sustained virological response (SVR; n = 149), respectively, failed to clear the virus (non-SVR; n = 183) after antiviral therapy. In the overall cohort, 9.3% of patients showed clinical signs of liver cirrhosis at 35 years after infection. Liver disease progression largely depended on HCV infection status. The highest proportion of patients with clinical signs of end-stage liver disease was observed in the non-SVR group (15.3%), whereas decreased cirrhosis rates were detected in the SVR group (6%) and in patients with self-limited HCV infection (1.1%; P = 6.2 × 10(-6)). Overall survival was significantly enhanced after SVR, compared to treatment-naïve patients or non-SVR (P = 0.027). CONCLUSION: The present study provides further evidence for a mild, but significant, disease progression at 35 years after infection in the German HCV (1b)-contaminated anti-D cohort. Patients with self-limited HCV infection or SVR after antiviral treatment were protected from progressive liver disease and showed the best clinical long-term outcome.


Assuntos
Hepatite C/epidemiologia , Adolescente , Adulto , Idoso , Antivirais/uso terapêutico , Progressão da Doença , Contaminação de Medicamentos , Feminino , Seguimentos , Alemanha/epidemiologia , Hepatite C/tratamento farmacológico , Hepatite C/etiologia , Humanos , Doença Iatrogênica/epidemiologia , Isoanticorpos , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Pessoa de Meia-Idade , Estudos Prospectivos , Imunoglobulina rho(D) , Análise de Sobrevida , Adulto Jovem
9.
J Hepatol ; 58(1): 24-30, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22925811

RESUMO

BACKGROUND & AIMS: The antiviral immune response against HCV by CD8+ T cells plays a central role in viral containment. In a large HCV genotype 1b outbreak in Ireland, HLA-B(∗)08 was identified as a risk allele for chronic infection and HLA-A(∗)03 and HLA-B(∗)27 were associated with higher clearance rates. Here we took advantage of a similar large common source HCV genotype 1b outbreak (East-German cohort) to determine the role of HLA class I alleles and the sequence of the infection source, in immunodominant CD8+ T cell epitopes for disease outcome. METHODS: HLA-type and IL28B genotype were determined in 216 patients with chronic and 95 with spontaneously resolved HCV infection. The viral sequence in immunodominant epitopes was determined in the infection source and in patients with chronic infection. RESULTS: In contrast to the Irish cohort, HLA-B(∗)08, HLA-A(∗)03 and HLA-B(∗)27 were neutral for disease outcome even when the cohort was stratified for the IL28B genotype. Sequence analysis of the immunodominant epitopes revealed that pre-existing substitutions in the infection source of both cohorts influenced the impact of the corresponding HLA-allele. The immunodominant epitopes presented by the "protective" alleles HLA-A(∗)03 and -B(∗)27 in the Irish cohort contained substitutions in the source virus of the East-German outbreak. Importantly, the pre-existing substitutions altered subsequent selection pressure and viral evolution in the East-German cohort. CONCLUSIONS: This study highlights that subtle sequence differences in the infection source may have profound effects on the ability to clear HCV infection in the presence of particular HLA class I alleles.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/virologia , Antígeno HLA-A3/genética , Antígeno HLA-B27/genética , Hepatite C Crônica/epidemiologia , Hepatite C Crônica/imunologia , Surtos de Doenças/estatística & dados numéricos , Suscetibilidade a Doenças/epidemiologia , Suscetibilidade a Doenças/imunologia , Epitopos de Linfócito T/imunologia , Genótipo , Alemanha/epidemiologia , Antígenos HLA-B/genética , Antígeno HLA-B8/genética , Humanos , Epitopos Imunodominantes/imunologia , Irlanda/epidemiologia , Fatores de Risco
10.
J Hepatol ; 55(6): 1201-6, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21703201

RESUMO

BACKGROUND & AIMS: The CCR5Δ32 mutation has been suspected to adversely affect outcomes of HCV infection, although reports have remained controversial. Here, we investigated the relative genetic contributions of the CCR5Δ32 deletion and the IL28B rs12979860 polymorphisms to spontaneous clearance of hepatitis C in a single-source outbreak. METHODS: We retrieved 396 Caucasian women (119 women with spontaneous HCV clearance) who had been infected with HCV genotype 1-contaminated anti-D immunoglobulin in 1978, and determined their IL28B and CCR5 alleles. RESULTS: IL28B CC, CT, and TT genotypes were found in 35.4%, 50%, and 14.6% of patients and corresponded to spontaneous clearance rates of 50%, 21.2%, and 12.1% (Chi(2)=38.7, p=5.0×10(-10)), respectively. CCR5 WT/WT, WT/Δ32, and Δ32/Δ32 genotypes were observed in 76%, 22.7%, and 1.3% of patients and corresponded to clearance rates of 33.2%, 21.2%, and 0% (Chi(2)=6.9, p=0.009), respectively. In a stepwise forward-conditional multivariate regression model both CCR5 (OR 2.1, p=0.01 for WT/WT) and IL28B genetic variants (OR 4.3, p=4.6×10(-10) for the C/C genotype) were identified as independent predictors of spontaneous HCV clearance. Importantly, favorable response rates were associated with the IL28B CC genotype only in CCR5 wild-type homozygous women, while HCV clearance in CCR5Δ32 carriers remained poor even in patients with the rs12979860 CC genotype. CONCLUSIONS: Both IL28B rs1297860 and CCR5Δ32 allelic variants are independent genetic determinants of spontaneous HCV clearance. The variable relative distribution between IL28B rs1297860 and CCR5Δ32 allelic variants in different populations may have masked the role of the CCR5Δ32 mutation in some studies.


Assuntos
Hepatite C/genética , Interleucinas/genética , Receptores CCR5/genética , Alelos , Estudos de Casos e Controles , Estudos de Coortes , Surtos de Doenças , Contaminação de Medicamentos , Feminino , Frequência do Gene , Genótipo , Alemanha/epidemiologia , Hepatite C/epidemiologia , Hepatite C/imunologia , Hepatite C/transmissão , Hepatite C/virologia , Humanos , Interferons , Polimorfismo de Nucleotídeo Único , Deleção de Sequência
11.
Gastroenterology ; 140(7): 2064-73, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21376049

RESUMO

BACKGROUND & AIMS: Hepatitis C virus (HCV) acquires mutations that allow it to escape the CD8+ T-cell response, although the extent to which this process contributes to viral evolution at the population level is not clear. We studied viral adaptation using data from a large outbreak of HCV genotype 1b infection that occurred among women immunized with contaminated immunoglobulin from 1977 to 1978. METHODS: The HCV nonstructural protein coding regions NS3-NS5B were sequenced from 78 patients, and mutations were mapped according to their location inside or outside previously described CD8+ T-cell epitopes. A statistical approach was developed to identify sites/regions under reproducible selection pressure associated with HLA class I. RESULTS: The frequency of nonsynonymous mutations was significantly higher inside previously described CD8+ T-cell epitopes than outside-particularly in NS3/4A and NS5B. We identified new regions that are under selection pressure, indicating that not all CD8+ T-cell epitopes have been identified; 6 new epitopes that interact with CD8+ T cells were identified and confirmed in vitro. In some CD8+ T-cell epitopes mutations were reproducibly identified in patients that shared the relevant HLA allele, indicating immune pressure at the population level. There was statistical support for selection of mutations in 18 individual epitopes. Interestingly, 14 of these were restricted by HLA-B allele. CONCLUSIONS: HLA class I-associated selection pressure on the nonstructural proteins and here predominantly on NS3/4A and NS5B promotes evolution of HCV. HLA-B alleles have a dominant effect in this selection process. Adaptation of HCV to the CD8+ T-cell response at the population level creates challenges for vaccine design.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Evolução Molecular , Hepacivirus/genética , Hepatite C/imunologia , Mutação , Proteínas não Estruturais Virais/genética , Linfócitos T CD8-Positivos/virologia , Proteínas de Transporte/genética , Proteínas de Transporte/imunologia , Análise Mutacional de DNA , Contaminação de Medicamentos , Epitopos , Feminino , Genótipo , Alemanha Oriental , Antígenos HLA-B/imunologia , Hepacivirus/imunologia , Hepatite C/virologia , Humanos , Imunoglobulinas/efeitos adversos , Peptídeos e Proteínas de Sinalização Intracelular , Modelos Genéticos , Modelos Estatísticos , Dados de Sequência Molecular , Fenótipo , Filogenia , Proteínas não Estruturais Virais/imunologia
12.
Gastroenterology ; 139(5): 1586-92, 1592.e1, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20637200

RESUMO

BACKGROUND & AIMS: A single nucleotide polymorphism (SNP) upstream of the IL28B gene has been associated with response of patients with chronic hepatitis C to therapy with pegylated interferon and ribavirin and also with spontaneous clearance of acute hepatitis C in a heterogeneous population. We analyzed the association between IL28B and the clinical presentation of acute hepatitis C virus (HCV) infection in a homogeneous population. METHODS: We analyzed the SNP rs12979860 in 190 women from the German anti-D cohort (infected with HCV genotype 1b via contaminated rhesus prophylaxis) and its association with spontaneous clearance. Clinical data were available in 136 women with acute infection who were also evaluated for IL28B genotype. Based on results of a TaqMan polymerase chain reaction assay, the rs12979860 SNP genotypes studied were C/C, C/T, or T/T. RESULTS: Spontaneous clearance was more common in patients with the C/C genotype (43/67; 64%) compared with C/T (22/90; 24%) or T/T (2/33; 6%) (P < .001). Jaundice during acute infection was more common among patients with C/C genotype (32.7%) than non-C/C patients (with C/T or T/T) (16.1%; P = .032). In C/C patients, jaundice during acute infection was not associated with an increased chance of spontaneous clearance (56.3%) compared with those without jaundice (60.6%). In contrast, in non-C/C patients, jaundice was associated with a higher likelihood of spontaneous clearance (42.9%) compared with those without jaundice (13.7%). CONCLUSIONS: The SNP rs12979860 upstream of IL28B is associated with spontaneous clearance of HCV. Women with the C/T or T/T genotype who did not develop jaundice had a lower chance of spontaneous clearance of HCV infection.


Assuntos
DNA/genética , Hepatite C/genética , Interleucinas/genética , Icterícia/genética , Polimorfismo Genético , Doença Aguda , Adulto , Feminino , Seguimentos , Genótipo , Hepatite C/complicações , Hepatite C/metabolismo , Humanos , Interferons , Interleucinas/metabolismo , Icterícia/etiologia , Icterícia/metabolismo , Reação em Cadeia da Polimerase , Prognóstico , Estudos Retrospectivos , Fatores de Tempo , Adulto Jovem
13.
Infect Genet Evol ; 9(5): 847-52, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19446659

RESUMO

Low-density lipoprotein receptor (LDLR) is involved in the entry of hepatitis C virus (HCV) in host cells. We investigated whether three single-nucleotide alterations within LDLR might be associated with the course of hepatitis C infection and response to antiviral therapy. We enrolled 651 individuals with chronic HCV infection who had received interferon-based combination therapy, 174 individuals with self-limited HCV infection, and 516 healthy controls. LDLR c.1171G>A, c.1413G>A, and c.*52G>A genotyping was performed by real-time PCR-based assays. HCV genotype 1-infected individuals who were homozygous for 3'UTR c.*52G were at increased risk for virologic non-response to antiviral therapy compared to virologic responders (66.3% vs. 51.0%, p=0.001). Furthermore, compared to healthy controls, self-limited HCV genotype 1 infection was significantly associated with c.1171A (15.1% vs. 6.6%, p=0.006) and negatively associated with c.1413G>A heterozygosity (33.0% vs. 46.1%, p=0.023). The data indicate that LDLR alterations are correlated with response to interferon-based combination therapy and with self-limitation of HCV 1 infection.


Assuntos
Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Receptores de LDL/genética , Regiões 3' não Traduzidas , Adulto , Idoso , Antivirais/uso terapêutico , Estudos de Casos e Controles , Estudos Transversais , Éxons , Feminino , Genótipo , Humanos , Interferons/uso terapêutico , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Polimorfismo de Nucleotídeo Único , Indução de Remissão , Remissão Espontânea , Adulto Jovem
14.
Virus Res ; 142(1-2): 1-9, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19103237

RESUMO

For many aspects of HCV research it would be very useful to have a set of replicons in which different genome regions are swapped by corresponding fragments from isolates of the same viral strain that might demonstrate different biological characteristics or bear evolving antigenic determinants. The isolates of the same HCV strain that are necessary for generation of such hybrid replicons might be obtained from a single-source outbreak of HCV infection. One such outbreak caused by the HCV AD78 strain, occurred in Germany due to infection of women by contaminated anti-D globulin. Using a sequential substitution of different segments of the Con1 replicon with the corresponding fragments from the AD78 strain of HCV, a set of chimeric Con1/AD78 subgenomic and full-length, AD78-based genomic replicons were generated. These replicons might be used as a new experimental tool for different aspects of HCV research, including studies of the nature of isolate-specific differences in interactions of the replicon with the host cell and analysis of the mechanisms of HCV resistance to antivirals. The newly generated full-length replicon can also be used for preparation of AD78-specific target cell lines, which may be invaluable for the analysis of the evolution of HCV cellular immune responses in the cohort of patients infected with the HCV AD78 strain.


Assuntos
Surtos de Doenças , Hepacivirus/genética , Hepatite C/epidemiologia , Replicon , Replicação Viral , Linhagem Celular , Variação Genética , Hepacivirus/fisiologia , Hepatite C/virologia , Humanos , Plasmídeos/genética
15.
J Virol ; 82(23): 11803-12, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18815309

RESUMO

The inherent sequence diversity of the hepatitis C virus (HCV) represents a major hurdle for the adaptive immune system to control viral replication. Mutational escape within targeted CD8 epitopes during acute HCV infection has been well documented and is one possible mechanism for T-cell failure. HLA-B*08 was recently identified as one HLA class I allele associated with spontaneous clearance of HCV replication. Selection of escape mutations in the immunodominant HLA-B*08-restricted epitope HSKKKCDEL(1395-1403) was observed during acute infection. However, little is known about the impact of escape mutations in this epitope on viral replication capacity. Their previously reported reversion back toward the consensus residue in patients who do not possess the B*08 allele suggests that the consensus sequence in this epitope is advantageous for viral replication in the absence of immune pressure. The aim of this study was to determine the impact of mutational escape from this immunodominant epitope on viral replication. We analyzed it with a patient cohort with chronic HCV genotype 1b infection and in a single-source outbreak (genotype 1b). Sequence changes in this highly conserved region are rare and selected almost exclusively in the presence of the HLA-B*08 allele. When tested in the subgenomic replicon (Con1), the observed mutations reduce viral replication compared with the prototype sequence. The results provide direct evidence that escape mutations in this epitope are associated with fitness costs and that the antiviral effect of HLA-B*08-restricted T cells is sufficiently strong to force the virus to adopt a relatively unfavorable sequence.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Antígenos HLA-B/fisiologia , Hepacivirus/imunologia , Proteínas não Estruturais Virais/imunologia , Alelos , Epitopos de Linfócito T/química , Genótipo , Antígenos HLA-B/genética , Hepacivirus/genética , Hepacivirus/fisiologia , Humanos , Epitopos Imunodominantes , Mutação , Replicação Viral
16.
Virus Res ; 125(1): 109-13, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17254660

RESUMO

To model HCV resistance to a treatment with interferon-alpha (IFN-alpha) and ribavirin, Huh7 cells, bearing HCV subgenomic replicons, were treated with these compounds for several weeks. Analysis of the cell clones, which were able to support replication of HCV RNA in the presence of high concentrations of these antivirals, demonstrated that the observed resistance was due to changes in the host cell phenotype but not to the emergence of resistant variants of the replicon. No changes in the type I IFN receptor mRNA levels or sequences were found in IFN-treated cells suggesting that the observed resistance of replicon-containing cells to IFN-alpha was caused by modifications of some other cellular factors. The resistance of cells to high concentrations of ribavirin was due to a single point mutation in the NS5A gene of the HCV replicon, and was not associated with a defect in a ribavirin uptake. This mutation, however, did not change the sensitivity of the replicon itself to this antiviral.


Assuntos
Farmacorresistência Viral , Hepacivirus/efeitos dos fármacos , Interferon-alfa/farmacologia , Replicon/efeitos dos fármacos , Ribavirina/farmacologia , Linhagem Celular , Genoma Viral , Hepacivirus/genética , Hepacivirus/fisiologia , Testes de Sensibilidade Microbiana , Transfecção , Replicação Viral/efeitos dos fármacos
17.
J Hepatol ; 43(4): 590-8, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16237783

RESUMO

BACKGROUND/AIMS: The natural course of the hepatitis C virus genotype 1b (HCV-1b) infection is still unclear but important for therapeutic decisions. There are few unbiased long-term follow-up studies with known dates of infection. METHODS: Between August 1978 and March 1979, 14 HCV-1b contaminated batches of anti-D immunoglobulin had been administered to 2867 women for prophylaxis of rhesus isoimmunization throughout East Germany. We reexamined 1980 women, representing 70% of the total cohort of 15 centers. RESULTS: After application of the contaminated anti-D, 93% of the recipients developed an acute hepatitis C. After 25 years, 86% of the 1833 affected women still tested positive for hepatitis C virus antibodies and 46% for HCV RNA. Only nine (0.5%) had overt liver cirrhosis, 30 women (1.5%) developed pre-cirrhotic stages and one HCC was diagnosed. Ten (0.5%) died of HCV related complications, half of these related to additional comorbidity. In the last 5 years, a continuous, but low increase of fibrotic scores was observed. CONCLUSIONS: Young women without comorbidity may clear HCV (1b) infection in more than half of the cases, or develop mild chronic hepatitis C. We confirmed the low risk of progression to cirrhosis in this cohort within 25 years.


Assuntos
Hepacivirus/genética , Hepatite C/epidemiologia , Adulto , Idade de Início , Consumo de Bebidas Alcoólicas , Carcinoma Hepatocelular/epidemiologia , Surtos de Doenças , Feminino , Genótipo , Alemanha/epidemiologia , Hepatite C/complicações , Humanos , Cirrose Hepática/epidemiologia , Neoplasias Hepáticas/epidemiologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Carga Viral
18.
Virology ; 336(2): 131-6, 2005 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-15892954

RESUMO

The hepatitis C virus (HCV) subgenomic replicon system was used to study a possible involvement of nonstructural protein 5A (NS5A) in the mechanisms of HCV resistance to interferon alpha (IFN-alpha). A series of chimeric HCV replicons was constructed. In these replicons, the NS5A gene in the backbone of the Con1 replicon was swapped by corresponding fragments obtained from four IFN-alpha responder and four IFN-alpha nonresponder patients that had been infected with the same HCV AD78 strain. Experiments with transfected Huh7 cells did not reveal significant differences in sensitivity of HCV RNA replication to IFN-alpha in cell clones, bearing chimeric Con1/AD78 replicons with NS5A sequences from IFN responders and nonresponders. Thus, these data provide no evidence that the NS5A protein contributes to the resistance of HCV replication to IFN-alpha.


Assuntos
Antivirais/farmacologia , Hepacivirus/efeitos dos fármacos , Interferon Tipo I/farmacologia , Proteínas não Estruturais Virais/fisiologia , Replicação Viral/efeitos dos fármacos , Sequência de Aminoácidos , Antivirais/uso terapêutico , Linhagem Celular Tumoral , Farmacorresistência Viral , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/virologia , Humanos , Interferon Tipo I/uso terapêutico , Dados de Sequência Molecular , Proteínas Recombinantes , Recombinação Genética , Replicon/genética , Alinhamento de Sequência , Proteínas não Estruturais Virais/genética
19.
World J Gastroenterol ; 11(12): 1843-7, 2005 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-15793878

RESUMO

AIM: Previous studies suggest that loss of bone mineral density (BMD) frequently occurs in patients with chronic viral liver disease, presenting with histologically proven liver cirrhosis. However, little is known about the occurrence of bone disease in non-cirrhotic patients with chronic hepatitis B or C. Therefore, it was the aim of this study to evaluate this particular population for BMD and bone turnover markers. METHODS: Biochemical markers of bone turnover and BMD were measured in 43 consecutive patients with HCV (n = 30) or HBV (n = 13) infection without histological evidence for liver cirrhosis. Mean age was 49 years (range 26-77 years). BMD was measured by dual X-ray absorptiometry in the femoral neck (FN) and the lumbar spine (LS) region. In addition, bone metabolism markers were measured. RESULTS: BMD was lowered in 25 (58%) of the patients with chronic hepatitis B or C (FN: 0.76 (0.53-0.99); LS: 0.96 (0.62-1.23) g/cm(2)). Eight (32%) osteopenic patients were diagnosed with osteoporosis. Bone-specific alkaline phosphatase (P = 0.005) and intact parathyroid hormone (iPTH) (P = 0.001) were significantly elevated in the more advanced stages of fibrosis. Mean T-score value was lower in patients with chronic hepatitis C as compared to patients suffering from chronic hepatitis B; however, the difference was not statistically significant (P = 0.09). CONCLUSION: There was a significantly reduced BMD in non-cirrhotic patients with chronic hepatitis B or C infection. Alterations of bone metabolism already occurred in advanced liver fibrosis without cirrhosis. According to our results, these secondary effects of chronic viral hepatitis should be further investigated.


Assuntos
Densidade Óssea , Osso e Ossos/metabolismo , Hepatite B Crônica/metabolismo , Hepatite C Crônica/metabolismo , Osteoporose/metabolismo , Adulto , Idoso , Biomarcadores , Feminino , Hepatite B Crônica/complicações , Hepatite C Crônica/complicações , Humanos , Cirrose Hepática , Masculino , Pessoa de Meia-Idade , Osteoporose/complicações , Osteoporose/patologia
20.
J Hepatol ; 41(4): 652-8, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15464247

RESUMO

BACKGROUND/AIMS: Interleukin-12 (IL-12) governs the Th1-type immune response, affecting the spontaneous and treatment-induced recovery from HCV-infection. We investigated whether the IL12B polymorphisms within the promoter region (4 bp insertion/deletion) and the 3'-UTR (1188-A/C), which have been reported to influence IL-12 synthesis, are associated with the outcome of HCV infection. METHODS: We analyzed 186 individuals with spontaneous HCV clearance, 501 chronically HCV infected patients, and 217 healthy controls. IL12B 3'-UTR and promoter genotyping was performed by Taqman-based assays with allele-specific oligonucleotide probes and PCR-based allele-specific DNA-amplification, respectively. RESULTS: The proportion of IL12B promoter and 3'-UTR genotypes did not differ significantly between the different cohorts. However, HCV genotype 1-infected patients with high baseline viremia carrying the IL12B 3'-UTR 1188-C-allele showed significantly higher sustained virologic response (SVR) rates (25.3% vs. 46% vs. 54.5% for A/A, A/C and C/C) due to reduced relapse rates (24.2% vs. 12% vs. zero % for A/A, A/C and C/C). CONCLUSIONS: IL12B 3'-UTR 1188-C-allele carriers appear to be capable of responding more efficiently to antiviral combination therapy as a consequence of a reduced relapse rate. No association of IL12B polymorphisms and self-limited HCV infection could be demonstrated.


Assuntos
Antivirais/uso terapêutico , Hepatite C/tratamento farmacológico , Hepatite C/fisiopatologia , Interleucina-12/genética , Polimorfismo Genético , Regiões 3' não Traduzidas , Adulto , Idoso , Alelos , Estudos de Casos e Controles , Quimioterapia Combinada , Feminino , Genótipo , Hepatite C/genética , Hepatite C Crônica/tratamento farmacológico , Hepatite C Crônica/genética , Hepatite C Crônica/patologia , Hepatite C Crônica/fisiopatologia , Heterozigoto , Humanos , Subunidade p40 da Interleucina-12 , Fígado/patologia , Masculino , Pessoa de Meia-Idade , Regiões Promotoras Genéticas/genética , Indução de Remissão , Remissão Espontânea , Índice de Gravidade de Doença
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