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1.
Nature ; 614(7947): 334-342, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36697826

RESUMEN

The liver is bathed in bacterial products, including lipopolysaccharide transported from the intestinal portal vasculature, but maintains a state of tolerance that is exploited by persistent pathogens and tumours1-4. The cellular basis mediating this tolerance, yet allowing a switch to immunity or immunopathology, needs to be better understood for successful immunotherapy of liver diseases. Here we show that a variable proportion of CD8+ T cells compartmentalized in the human liver co-stain for CD14 and other prototypic myeloid membrane proteins and are enriched in close proximity to CD14high myeloid cells in hepatic zone 2. CD14+CD8+ T cells preferentially accumulate within the donor pool in liver allografts, among hepatic virus-specific and tumour-infiltrating responses, and in cirrhotic ascites. CD14+CD8+ T cells exhibit increased turnover, activation and constitutive immunomodulatory features with high homeostatic IL-10 and IL-2 production ex vivo, and enhanced antiviral/anti-tumour effector function after TCR engagement. This CD14+CD8+ T cell profile can be recapitulated by the acquisition of membrane proteins-including the lipopolysaccharide receptor complex-from mononuclear phagocytes, resulting in augmented tumour killing by TCR-redirected T cells in vitro. CD14+CD8+ T cells express integrins and chemokine receptors that favour interactions with the local stroma, which can promote their induction through CXCL12. Lipopolysaccharide can also increase the frequency of CD14+CD8+ T cells in vitro and in vivo, and skew their function towards the production of chemotactic and regenerative cytokines. Thus, bacterial products in the gut-liver axis and tissue stromal factors can tune liver immunity by driving myeloid instruction of CD8+ T cells with immunomodulatory ability.


Asunto(s)
Linfocitos T CD8-positivos , Tolerancia Inmunológica , Receptores de Lipopolisacáridos , Lipopolisacáridos , Hígado , Células Mieloides , Humanos , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/efectos de los fármacos , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD8-positivos/metabolismo , Receptores de Lipopolisacáridos/metabolismo , Lipopolisacáridos/inmunología , Lipopolisacáridos/farmacología , Células Mieloides/inmunología , Células Mieloides/metabolismo , Neoplasias/inmunología , Neoplasias/patología , Receptores de Antígenos de Linfocitos T/inmunología , Receptores de Antígenos de Linfocitos T/metabolismo , Tolerancia Inmunológica/efectos de los fármacos , Tolerancia Inmunológica/inmunología , Hígado/efectos de los fármacos , Hígado/inmunología , Hígado/patología , Hígado/virología , Interleucina-2/biosíntesis , Interleucina-2/inmunología , Quimiotaxis de Leucocito , Bacterias/inmunología , Intestinos/inmunología , Intestinos/microbiología
2.
J Med Virol ; 96(7): e29787, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38988177

RESUMEN

Chronic hepatitis C virus infection (HCV) causes liver inflammation and fibrosis, leading to the development of severe liver disease, such as cirrhosis or hepatocellular carcinoma (HCC). Approval of direct-acting antiviral drug combinations has revolutionized chronic HCV therapy, with virus eradication in >98% of the treated patients. The efficacy of these treatments is such that it is formally possible for cured patients to carry formerly infected cells that display irreversible transcriptional alterations directly caused by chronic HCV Infection. Combining differential transcriptomes from two different persistent infection models, we observed a major reversion of infection-related transcripts after complete infection elimination. However, a small number of transcripts were abnormally expressed in formerly infected cells. Comparison of the results obtained in proliferating and growth-arrested cell culture models suggest that permanent transcriptional alterations may be established by several mechanisms. Interestingly, some of these alterations were also observed in the liver biopsies of virologically cured patients. Overall, our data suggest a direct and permanent impact of persistent HCV infection on the host cell transcriptome even after virus elimination, possibly contributing to the development of HCC.


Asunto(s)
Antivirales , Hepacivirus , Hepatitis C Crónica , Humanos , Antivirales/farmacología , Antivirales/uso terapéutico , Hepacivirus/genética , Hepacivirus/efectos de los fármacos , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/virología , Transcriptoma , Infección Persistente/virología , Perfilación de la Expresión Génica , Hígado/virología , Hígado/patología , Carcinoma Hepatocelular/virología , Transcripción Genética/efectos de los fármacos
3.
J Hepatol ; 74(5): 1064-1074, 2021 05.
Artículo en Inglés | MEDLINE | ID: mdl-33278456

RESUMEN

BACKGROUND & AIMS: Factors associated with a successful outcome upon nucleos(t)ide analogue (NA) treatment withdrawal in HBeAg-negative chronic hepatitis B (CHB) patients have yet to be clarified. The objective of this study was to analyse the HBV-specific T cell response, in parallel with peripheral and intrahepatic viral parameters, in patients undergoing NA discontinuation. METHODS: Twenty-seven patients without cirrhosis with HBeAg-negative CHB with complete viral suppression (>3 years) were studied prospectively. Intrahepatic HBV-DNA (iHBV-DNA), intrahepatic HBV-RNA (iHBV-RNA), and covalently closed circular DNA (cccDNA) were quantified at baseline. Additionally, serum markers (HBV-DNA, HBsAg, HBV core-related antigen [HBcrAg] and HBV-RNA) and HBV-specific T cell responses were analysed at baseline and longitudinally throughout follow-up. RESULTS: After a median follow-up of 34 months, 22/27 patients (82%) remained off-therapy, of whom 8 patients (30% of the total cohort) lost HBsAg. Baseline HBsAg significantly correlated with iHBV-DNA and iHBV-RNA, and these parameters were lower in patients who lost HBsAg. All patients had similar levels of detectable cccDNA regardless of their clinical outcome. Patients achieving functional cure had baseline HBsAg levels ≤1,000 IU/ml. Similarly, an increased frequency of functional HBV-specific CD8+ T cells at baseline was associated with sustained viral control off treatment. These HBV-specific T cell responses persisted, but did not increase, after treatment withdrawal. A similar, but not statistically significant trend, was observed for HBV-specific CD4+ T cell responses. CONCLUSIONS: Decreased cccDNA transcription and low HBsAg levels are associated with HBsAg loss upon NA discontinuation in patients with HBeAg-negative CHB. The presence of functional HBV-specific T cells at baseline are associated with a successful outcome after treatment withdrawal. LAY SUMMARY: Nucleos(t)ide analogue therapy can be discontinued in a high proportion of chronic hepatitis B patients without cirrhosis. The strength of HBV-specific immune T cell responses may contribute to successful viral control after antiviral treatment interruption. Our comprehensive study provides in-depth data on virological and immunological factors than can help guide individualised therapy in patients with chronic hepatitis B.


Asunto(s)
ADN Viral/aislamiento & purificación , Antígenos de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica , Inmunidad Celular , Hígado , Nucleósidos/uso terapéutico , Privación de Tratamiento/estadística & datos numéricos , Antivirales/uso terapéutico , Biomarcadores/sangre , ADN Circular/aislamiento & purificación , Femenino , Antígenos de la Hepatitis B/análisis , Antígenos de la Hepatitis B/aislamiento & purificación , Antígenos de Superficie de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/sangre , Hepatitis B Crónica/diagnóstico , Humanos , Inmunidad Celular/efectos de los fármacos , Inmunidad Celular/inmunología , Hígado/patología , Hígado/virología , Masculino , Persona de Mediana Edad , Planificación de Atención al Paciente
4.
PLoS Pathog ; 14(9): e1007284, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30226904

RESUMEN

Hepatitis C virus (HCV) infection constitutes a significant health burden worldwide, because it is a major etiologic agent of chronic liver disease, cirrhosis and hepatocellular carcinoma. HCV replication cycle is closely tied to lipid metabolism and infection by this virus causes profound changes in host lipid homeostasis. We focused our attention on a phosphatidate phosphate (PAP) enzyme family (the lipin family), which mediate the conversion of phosphatidate to diacylglycerol in the cytoplasm, playing a key role in triglyceride biosynthesis and in phospholipid homeostasis. Lipins may also translocate to the nucleus to act as transcriptional regulators of genes involved in lipid metabolism. The best-characterized member of this family is lipin1, which cooperates with lipin2 to maintain glycerophospholipid homeostasis in the liver. Lipin1-deficient cell lines were generated by RNAi to study the role of this protein in different steps of HCV replication cycle. Using surrogate models that recapitulate different aspects of HCV infection, we concluded that lipin1 is rate limiting for the generation of functional replicase complexes, in a step downstream primary translation that leads to early HCV RNA replication. Infection studies in lipin1-deficient cells overexpressing wild type or phosphatase-defective lipin1 proteins suggest that lipin1 phosphatase activity is required to support HCV infection. Finally, ultrastructural and biochemical analyses in replication-independent models suggest that lipin1 may facilitate the generation of the membranous compartment that contains functional HCV replicase complexes.


Asunto(s)
Hepacivirus/fisiología , Hepacivirus/patogenicidad , Hepatitis C/metabolismo , Hepatitis C/virología , Fosfatidato Fosfatasa/metabolismo , ARN Polimerasa Dependiente del ARN/metabolismo , Línea Celular , Hepacivirus/genética , Hepatitis C/etiología , Interacciones Huésped-Patógeno , Humanos , Metabolismo de los Lípidos , Fosfatidato Fosfatasa/antagonistas & inhibidores , Fosfatidato Fosfatasa/genética , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Interferente Pequeño/genética , ARN Viral/genética , ARN Viral/metabolismo , Replicación Viral
5.
J Viral Hepat ; 27(12): 1408-1418, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32812325

RESUMEN

Chronic hepatitis C virus (HCV) infection impairs HCV CD8+ T-cell responses, while it could influence immune responses towards unrelated viruses/vaccines (e.g. cytomegalovirus, CMV, and influenza, Flu). The aim of our study was to delineate whether restoration of these virus-specific CD8+ T cells occurs after direct-acting antiviral (DAA) therapies and particularly in patients with cirrhosis. We performed longitudinal analysis (baseline, week 4, follow-up [FU] 12 and FU48) of virus-specific CD8+ T cells by multicolour flow cytometry in HCV-cirrhotic patients undergoing DAA therapy (n = 26) after in vitro expansion with immunodominant HCV, CMV and Flu epitopes restricted by HLA-A*02. HCV noncirrhotic patients (n = 9) and healthy individuals (n = 10) served as controls. We found that the proliferative capacity of HCV-specific CD8+ T cells increased from baseline up to FU48 in a significant proportion of cirrhotic and noncirrhotic patients. Nevertheless, these cells remained poor cytokine producers in both patient groups, regardless of the down-regulation of inhibitory co-regulatory receptors in HCV-cirrhotic patients at FU48. Likewise, high expression levels of these exhaustion markers were detected in CMV-/Flu-specific CD8+ T cells in HCV-cirrhotic patients at all time points, albeit without affecting their proliferative capacity or cytokine production. We conclude that DAA therapies induce restoration of the proliferative capacity of HCV-specific CD8+ T cells. However, these cells remain phenotypically and functionally impaired. Contrarily, the 'exhausted' phenotype in CMV-/Flu-specific CD8+ T cells in HCV-cirrhotic patients did not associate with their functions. Larger studier with longer follow-up may elucidate whether this complex interplay influences the outcome of cirrhotic patients.


Asunto(s)
Hepatitis C Crónica , Hepatitis C , Antivirales/uso terapéutico , Linfocitos T CD8-positivos , Genotipo , Hepacivirus , Hepatitis C/tratamiento farmacológico , Hepatitis C Crónica/complicaciones , Hepatitis C Crónica/tratamiento farmacológico , Humanos , Cirrosis Hepática/tratamiento farmacológico
6.
J Med Virol ; 92(8): 1359-1362, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31743439

RESUMEN

Hepatitis E virus (HEV) and hepatitis A virus (HAV) are both secreted in feces. Despite HEV transmission in Europe is mainly zoonotic, person-to-person transmission has not been completely excluded. Men who have sex with men (MSM) constitute a high-risk group for HAV mostly due to oral sex. We investigated the potential transmission of HEV during an acute hepatitis A (AHA) outbreak mainly affecting MSM. One hundred and two patients were diagnosed with AHA. Sixty-nine (68%) self-reported to be MSM, 75% of whom had high-risk sexual behaviors and 46% had suffered previous sexually transmitted diseases. We collected serum from 85 (83%) patients during AHA. HEV-IgG seroprevalence was not different among MSM (7%) compared with non-MSM (8%) patients. Two patients had positive anti-HEV-IgM, but all samples tested negative for HEV-RNA. These results suggest that HEV does not spread by sexual contact or person-to-person in our area.


Asunto(s)
Brotes de Enfermedades , Hepatitis A/epidemiología , Anticuerpos Antihepatitis/sangre , Hepatitis E/epidemiología , Hepatitis E/inmunología , Adulto , Virus de la Hepatitis E , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Factores de Riesgo , Estudios Seroepidemiológicos , Minorías Sexuales y de Género , España/epidemiología , Encuestas y Cuestionarios
7.
J Gen Virol ; 100(1): 63-68, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-30451649

RESUMEN

Cholestatic hepatitis C (CHC) is a severe form of hepatitis C virus (HCV) infection recurrence that leads to high graft loss rates early after liver transplantation (LT). To investigate the pathogenic mechanisms of CHC, we analysed HCV quasispecies in CHC patients compared to a control group (mild hepatitis C recurrence) by deep pyrosequencing. At the time of LT, NS5B quasispecies complexity was similar between the two groups but, after LT, it decreased more sharply in CHC patients than in the control group. Interestingly, the major variant before LT propagated efficiently and remained as the dominant sequence after LT in 62 % of CHC patients versus 11 % of controls (P=0.031). Sequence analysis of the complete non-structural region in a limited number of patients revealed a potential 12 aa signature specific to the CHC group. These data suggest that intrinsic molecular determinants in the circulating HCV quasispecies may provide a fitness advantage, contributing to the development of CHC.


Asunto(s)
Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/patología , Hepatitis C Crónica/virología , Ictericia Obstructiva/etiología , Ictericia Obstructiva/virología , Trasplante de Hígado , Anciano , Femenino , Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Persona de Mediana Edad , Proteínas no Estructurales Virales/genética
8.
Liver Transpl ; 25(2): 302-310, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30375165

RESUMEN

The development of noninvasive biomarkers that reflect the state of immunosuppression (IS) remains an unmet need in liver transplantation (LT). Torque Teno virus (TTV) is a highly prevalent, nonpathogenic DNA virus whose plasma levels may be associated with the immune status of the host. The aim of this study was to assess the role of TTV as a biomarker of IS in LT recipients. TTV DNA in plasma was quantified by real-time polymerase chain reaction at different time points during the first year after transplant in a prospectively followed cohort of 63 de novo LT recipients, and any correlation between TTV DNA and biopsy-proven acute cellular rejection (ACR) and opportunistic infections was then evaluated. In addition, TTV DNA was studied in 10 longterm LT recipients in monotherapy with tacrolimus, 10 tolerant recipients, and 10 healthy controls. TTV was detected in the plasma of all patients. Among the 63 LT recipients, 20 episodes of ACR were diagnosed, and there were 28 opportunistic infections, 26 of them being cytomegalovirus (CMV) infections. TTV viremia was significantly lower during ACR (4.41 versus 5.95 log10 copies/mL; P = 0.002) and significantly higher during CMV infections (5.79 versus 6.59 log10 copies/mL; P = 0.009). The area under the receiver operating characteristic curve of TTV viral load for the diagnosis of moderate ACR was 0.869, with a sensitivity and negative predictive value of 100%, respectively, for a cutoff point of 4.75 log10 copies/mL. There were no statistically significant differences in TTV DNA in either longterm or tolerant patients and healthy controls. In conclusion, plasma TTV DNA levels are associated with immune-related events after LT and could constitute a potential biomarker of the state of IS during the first months after transplant.


Asunto(s)
Infecciones por Citomegalovirus/diagnóstico , Rechazo de Injerto/diagnóstico , Tolerancia Inmunológica , Trasplante de Hígado/efectos adversos , Infecciones Oportunistas/diagnóstico , Torque teno virus/aislamiento & purificación , Adulto , Anciano , Aloinjertos/inmunología , Aloinjertos/patología , Biomarcadores/sangre , Biopsia , Citomegalovirus/aislamiento & purificación , Citomegalovirus/patogenicidad , Infecciones por Citomegalovirus/sangre , Infecciones por Citomegalovirus/inmunología , ADN Viral/aislamiento & purificación , Femenino , Estudios de Seguimiento , Rechazo de Injerto/inmunología , Rechazo de Injerto/prevención & control , Interacciones Microbiota-Huesped/inmunología , Humanos , Terapia de Inmunosupresión/efectos adversos , Hígado/inmunología , Hígado/patología , Masculino , Persona de Mediana Edad , Infecciones Oportunistas/sangre , Infecciones Oportunistas/inmunología , Periodo Posoperatorio , Estudios Prospectivos , Reacción en Cadena en Tiempo Real de la Polimerasa , Estudios Retrospectivos , Torque teno virus/genética , Torque teno virus/inmunología , Carga Viral , Viremia/inmunología , Viremia/virología
10.
J Viral Hepat ; 25(12): 1515-1525, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30141252

RESUMEN

The emergence of resistance-associated substitutions (RASs) can compromise the high efficacy of direct-acting antivirals (DAAs). Little is known about RASs selection at very early time points during DAA treatment. Therefore, we analyzed the potential emergence of RASs immediately after therapy initiation. Samples of 71 patients treated with different DAAs were collected at baseline, during therapy (hours 4 and 8; days 1-7; weeks 2-4) or until target not detected. HCV-RNA levels were determined by qPCR, and RASs were detected by deep sequencing. Sixty-three (89%) patients achieved a sustained virological response (SVR), 7 (10%) relapsed, and 1 (1%) experienced a breakthrough. Almost all non-SVR (7/8, 88%) showed RASs either at baseline or relapse. High-frequency RASs detected at baseline (Y93H and L159F+C316N) remained detectable at early time points during therapy and reappeared as most prevalent substitutions at relapse. Conversely, emergent RASs at relapse (Q80R, D168E/V, R155K and L31V) were not observed during the first hours-days, before HCV-RNA became undetectable. HCV-RNA decay and genetic evolution of the quasispecies followed a similar pattern during the first hours of therapy in SVR and non-SVR patients. In conclusion, the absence of early RASs selection and the similar dynamics of HCV kinetics and quasispecies in SVR and non-SVR patients after therapy initiation suggest that RASs selection may occur at later stages in the remaining reservoir, where viral populations persist hidden at very low replication levels. Nevertheless, we cannot completely exclude very early selection, when RASs are present below the sensitivity limit of deep sequencing.


Asunto(s)
Sustitución de Aminoácidos , Antivirales/administración & dosificación , Farmacorresistencia Viral , Hepacivirus/efectos de los fármacos , Hepacivirus/aislamiento & purificación , Hepatitis C Crónica/tratamiento farmacológico , Carga Viral , Adulto , Anciano , Anciano de 80 o más Años , Antivirales/farmacología , Femenino , Hepacivirus/genética , Hepatitis C Crónica/virología , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , ARN Viral/sangre , ARN Viral/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Recurrencia , Selección Genética , Respuesta Virológica Sostenida
11.
Liver Int ; 38(3): 388-398, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-28782251

RESUMEN

Over the last few years, many reports have defined several types of RNA cell granules composed of proteins and messenger RNA (mRNA) that regulate gene expression on a post-transcriptional level. Processing bodies (P-bodies) and stress granules (SGs) are among the best-known RNA granules, only detectable when they accumulate into very dynamic cytosolic foci. Recently, a tight association has been found between positive-stranded RNA viruses, including hepatitis C virus (HCV), and these granules. The present article offers a comprehensive review on the complex and paradoxical relationship between HCV, P-bodies and SGs from a translational perspective. Despite the fact that components of P-bodies and SGs have assiduously controlled mRNA expression, either by sequestration or degradation, for thousands of years, HCV has learned how to dangerously exploit certain of them for its own benefit in an endless biological war. Thus, HCV has gained the ability to hack ancient host machineries inherited from prokaryotic times. While P-bodies and SGs are crucial to the HCV cycle, in the interferon-free era we still lack detailed knowledge of the mechanisms involved, processes that may underlie the long-term complications of HCV infection.


Asunto(s)
Gránulos Citoplasmáticos/fisiología , Hepacivirus/fisiología , ARN Mensajero/metabolismo , Línea Celular , Expresión Génica , Hepacivirus/genética , Humanos , Microscopía Fluorescente , ARN Viral/genética , Replicación Viral/fisiología
12.
Liver Int ; 38(4): 588-593, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28980376

RESUMEN

BACKGROUND & AIMS: Acute hepatitis A is transmitted mainly via the faecal-oral route and/or contaminated aliment. Furthermore, several outbreaks in the men who have sex with men (MSM) population classified hepatitis A as a sexually transmitted disease (STD). We aimed to clarify an ongoing hepatitis A outbreak in Barcelona with respect to patients' characteristics and viral phylogenetic analysis. METHODS: We prospectively analyzed 46 cases of hepatitis A infection that were registered in our hospital between January and June 2017. We evaluated demographics data, risk factors, presenting symptoms, sexual orientation, comorbidities and further STD infections. The phylogenetic correlation of the current circulating viruses among them and other hepatitis A strains was assessed by sequencing of the VP1/P2A region. RESULTS: Most patients were male (44, 96%) with median age 33.5 years (range 28-50). Thirty-one (67%) were MSM and 18 (39%) required hospitalization. Molecular phylogenetic analyses revealed that all patients were infected by hepatitis A subgenotype IA strains. Moreover, current strains comprised 3 distinct clusters, previously reported in ongoing outbreaks in the United Kingdom, Berlin and the Netherlands. However, these strains were phylogenetically diverse to those previously reported in Barcelona metropolitan region. CONCLUSIONS: Ongoing hepatitis A outbreak in Barcelona affects primarily the MSM community and is phylogenetically linked to current hepatitis A outbreaks described in other European countries. As a result of the high admission rate, these outbreaks may impact the admission pattern of referral liver units. Control measures, for example vaccinations programs tailored to the MSM community, must be taken to control further spreading.


Asunto(s)
Brotes de Enfermedades/estadística & datos numéricos , Hepatitis A/epidemiología , Homosexualidad Masculina , Enfermedad Aguda , Adulto , Femenino , Virus de la Hepatitis A Humana/genética , Virus de la Hepatitis A Humana/aislamiento & purificación , Hospitalización/estadística & datos numéricos , Humanos , Masculino , Persona de Mediana Edad , Filogenia , Factores de Riesgo , España/epidemiología
13.
Gastroenterology ; 151(4): 633-636.e3, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27373513

RESUMEN

We assessed the presence of hepatitis C virus (HCV) RNA in liver explants from 39 patients awaiting liver transplantation who were treated with an interferon-free regimen and had undetectable serum HCV RNA at the time of liver transplantation. Interestingly, HCV RNA was detected in most liver explants (67%). Patients with HCV RNA-positive explants had received shorter courses of treatment, and HCV RNA was undetectable in serum for shorter periods before transplantation compared to patients with HCV RNA-negative explants (P = .014 and P = .013, respectively). Levels of HCV RNA in explants were significantly higher in patients with a relapse of HCV infection than patients who responded to treatment (P = .016), but most patients (85%) with residual HCV-RNA in the explant achieved a sustained virologic response after receiving their liver transplant.


Asunto(s)
Antivirales/administración & dosificación , Hepacivirus/efectos de los fármacos , Hepatitis C/virología , Trasplante de Hígado , Hígado/virología , ARN Viral/efectos de los fármacos , Trasplantes/virología , Femenino , Hepacivirus/genética , Hepatitis C/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , ARN Viral/análisis , ARN Viral/sangre , Recurrencia , Respuesta Virológica Sostenida , Listas de Espera
14.
Liver Int ; 36 Suppl 1: 72-7, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26725901

RESUMEN

Hepatitis B virus (HBV) remains a public health concern with 240 million people affected worldwide. HBV is an hepadnavirus that replicates its genome in hepatocytes. One of the key steps of the viral life cycle is the formation of cccDNA - covalently closed circular DNA - in the nucleus, the equivalent of a viral mini-chromosome that acts as a template for subsequent virus replication. Current antiviral medications are not effective in eradicating cccDNA, which can persist in the infected liver even in the absence of detectable HBV DNA or HBsAg in the blood. cccDNA cannot be measured in serum, and few surrogate markers have been proposed. Persistent cccDNA has been associated with various clinical events, including viral reactivation induced by immunosuppressive therapies, HBV recurrence after liver transplantation and hepatocellular carcinoma (HCC). cccDNA remains the main target to achieve a cure of HBV infection, thus extensive efforts are being made to develop new antiviral concepts to degrade or silence cccDNA.


Asunto(s)
Antivirales/uso terapéutico , ADN Circular/sangre , ADN Viral/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B Crónica/tratamiento farmacológico , Biomarcadores , Carcinoma Hepatocelular/cirugía , Virus de la Hepatitis B , Hepatitis B Crónica/epidemiología , Hepatocitos/metabolismo , Humanos , Neoplasias Hepáticas/cirugía , Trasplante de Hígado/métodos , Recurrencia , Activación Viral , Replicación Viral
15.
J Hepatol ; 62(4): 785-90, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25463546

RESUMEN

BACKGROUND & AIMS: Decoding the myriad of interactions that hepatitis C virus (HCV) establishes with infected cells is mandatory to obtain a complete understanding of HCV biology and its associated pathogenesis. We and others have previously found that HCV infection disrupts the formation of P-bodies in cell culture. These are cytoplasmic RNA granules with key roles in post-transcriptional regulation of gene expression. Therefore, P-body disruption might have consequences beyond viral propagation. However, whether P-body disruption occurs also in vivo is unknown. Aim of this study was to address this important issue. METHODS: Formalin-fixed paraffin-embedded liver biopsies from four groups of patients (healthy donors, patients with non-virus related liver inflammation, HCV- and HBV-infected patients) were immunostained to detect DDX6 and Dcp1, two core P-body components. Changes in the localization of these proteins were assessed by confocal microscopy. RESULTS: HCV specifically inhibited P-body formation in hepatocytes from human livers regardless of viral genotype, inflammation grade or whether the infection was recent or long established. Importantly, this alteration was reversed once HCV was eliminated by therapy. Furthermore, we observed in vivo an unexpected heterogeneity in P-body composition, which might reflect functional specializations. CONCLUSIONS: This is the first comprehensive in vivo P-body analysis that links a pathogenic condition to P-body alterations. Because of their role in gene expression, the alteration of P-bodies should be further studied to understand fully complex HCV-associated pathologies.


Asunto(s)
Gránulos Citoplasmáticos/fisiología , ARN Helicasas DEAD-box , Endopeptidasas , Hepacivirus , Hepatitis C Crónica , Proteínas Proto-Oncogénicas , Adulto , ARN Helicasas DEAD-box/biosíntesis , ARN Helicasas DEAD-box/inmunología , Endopeptidasas/biosíntesis , Endopeptidasas/inmunología , Femenino , Hepacivirus/patogenicidad , Hepacivirus/fisiología , Hepatitis C Crónica/inmunología , Hepatitis C Crónica/metabolismo , Hepatocitos/metabolismo , Interacciones Huésped-Patógeno , Humanos , Masculino , Persona de Mediana Edad , Proteínas Proto-Oncogénicas/biosíntesis , Proteínas Proto-Oncogénicas/inmunología , Carga Viral
16.
J Gen Virol ; 96(12): 3493-3498, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26395289

RESUMEN

The allocation of liver grafts from hepatitis C virus (HCV)-positive donors in HCV-infected liver transplant (LT) recipients leads to infection with two different viral populations. In a previous study, we examined quasispecies dynamics during reinfection by clonal sequencing, which did not allow an accurate characterization of coexistence and competition events. To overcome this limitation, here we used deep-sequencing analysis of a fragment of the HCV NS5B gene in six HCV-infected LT recipients who received HCV-infected grafts. Successive expansions and contractions of quasispecies complexity were observed, evolving in all cases towards a more homogeneous population. The population that became dominant was the one displaying the highest mutant spectrum complexity. In four patients, coexistence of minority mutants, derived from the donor or the recipient, were detected. In conclusion, our study shows that, during reinfection with a different HCV strain in LT recipients, the viral population with the highest diversity always becomes dominant.


Asunto(s)
Hepacivirus/genética , Hepatitis C/terapia , Hepatitis C/virología , Trasplante de Hígado , Regulación Viral de la Expresión Génica , Genotipo , Hepacivirus/clasificación , Hepacivirus/fisiología , Humanos , Hígado/virología , Interacciones Microbianas/genética , Mutación , Filogenia , Donantes de Tejidos , Proteínas no Estructurales Virales/genética , Proteínas no Estructurales Virales/metabolismo
17.
J Clin Microbiol ; 53(1): 219-26, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25378574

RESUMEN

Hepatitis C virus (HCV) is classified into seven major genotypes and 67 subtypes. Recent studies have shown that in HCV genotype 1-infected patients, response rates to regimens containing direct-acting antivirals (DAAs) are subtype dependent. Currently available genotyping methods have limited subtyping accuracy. We have evaluated the performance of a deep-sequencing-based HCV subtyping assay, developed for the 454/GS-Junior platform, in comparison with those of two commercial assays (Versant HCV genotype 2.0 and Abbott Real-time HCV Genotype II) and using direct NS5B sequencing as a gold standard (direct sequencing), in 114 clinical specimens previously tested by first-generation hybridization assay (82 genotype 1 and 32 with uninterpretable results). Phylogenetic analysis of deep-sequencing reads matched subtype 1 calling by population Sanger sequencing (69% 1b, 31% 1a) in 81 specimens and identified a mixed-subtype infection (1b/3a/1a) in one sample. Similarly, among the 32 previously indeterminate specimens, identical genotype and subtype results were obtained by direct and deep sequencing in all but four samples with dual infection. In contrast, both Versant HCV Genotype 2.0 and Abbott Real-time HCV Genotype II failed subtype 1 calling in 13 (16%) samples each and were unable to identify the HCV genotype and/or subtype in more than half of the non-genotype 1 samples. We concluded that deep sequencing is more efficient for HCV subtyping than currently available methods and allows qualitative identification of mixed infections and may be more helpful with respect to informing treatment strategies with new DAA-containing regimens across all HCV subtypes.


Asunto(s)
Genotipo , Hepacivirus/clasificación , Hepacivirus/genética , Hepatitis C/virología , Secuenciación de Nucleótidos de Alto Rendimiento , Filogenia , Proteínas no Estructurales Virales/genética , Técnicas de Genotipaje , Hepatitis C/diagnóstico , Humanos , Juego de Reactivos para Diagnóstico
18.
J Virol ; 88(1): 667-78, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24173227

RESUMEN

Serine is encoded by two divergent codon types, UCN and AGY, which are not interchangeable by a single nucleotide substitution. Switching between codon types therefore occurs via intermediates (threonine or cysteine) or via simultaneous tandem substitutions. Hepatitis C virus (HCV) chronically infects 2 to 3% of the global population. The highly variable glycoproteins E1 and E2 decorate the surface of the viral envelope, facilitate cellular entry, and are targets for host immunity. Comparative sequence analysis of globally sampled E1E2 genes, coupled with phylogenetic analysis, reveals the signatures of multiple archaic codon-switching events at seven highly conserved serine residues. Limited detection of intermediate phenotypes indicates that associated fitness costs restrict their fixation in divergent HCV lineages. Mutational pathways underlying codon switching were probed via reverse genetics, assessing glycoprotein functionality using multiple in vitro systems. These data demonstrate selection against intermediate phenotypes can act at the structural/functional level, with some intermediates displaying impaired virion assembly and/or decreased capacity for target cell entry. These effects act in residue/isolate-specific manner. Selection against intermediates is also provided by humoral targeting, with some intermediates exhibiting increased epitope exposure and enhanced neutralization sensitivity, despite maintaining a capacity for target cell entry. Thus, purifying selection against intermediates limits their frequencies in globally sampled strains, with divergent functional constraints at the protein level restricting the fixation of deleterious mutations. Overall our study provides an experimental framework for identification of barriers limiting viral substitutional evolution and indicates that serine codon-switching represents a genomic "fossil record" of historical purifying selection against E1E2 intermediate phenotypes.


Asunto(s)
Codón , Evolución Molecular , Glicoproteínas/química , Hepacivirus/química , Serina/química , Glicoproteínas/genética , Fenotipo , Filogenia
20.
J Hepatol ; 61(2): 270-7, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24703854

RESUMEN

BACKGROUND & AIMS: Significant liver fibrosis (F ⩾ 2) and portal hypertension (hepatic venous pressure gradient [HVPG] ⩾ 6 mmHg) 1 year after liver transplantation (LT) are predictors of severe hepatitis C recurrence. Periportal sinusoidal fibrosis (SF) is an early expression of the fibrogenic process in response to liver injury. We aimed to evaluate whether SF in early liver biopsies represents an early and accurate marker for identifying patients with severe HCV recurrence after LT. METHODS: A total of 101 HCV LT patients with early biopsy (<6 months), and HVPG measurement and/or liver biopsy one year after LT were included. Early biopsies were stained with Sirius Red and SF was graded semi-quantitatively. Results were compared between groups (significant SF vs. non-significant SF) and correlated with the development of severe HCV recurrence one year after LT. RESULTS: Patients with early significant SF had older donor age and higher necroinflammatory activity (NIA). The presence of early significant SF enabled identification of 78.9% and 90.6% of patients with F ⩾ 2 and HVPG ⩾ 6 mmHg, respectively, one year after LT. Donor age and NIA were independent predictors of significant fibrosis (F ⩾ 2) one year after LT, whereas donor age, ALT (3 months), NIA, and SF grade were independent predictors of portal hypertension (HVPG ⩾ 6). CONCLUSIONS: Significant SF in early biopsies is a good predictor of severe hepatitis C recurrence. This histological finding, when combined with simple variables, may be useful to select the best candidates for early antiviral therapy after LT.


Asunto(s)
Hepatitis C Crónica/complicaciones , Cirrosis Hepática/diagnóstico , Trasplante de Hígado/efectos adversos , Adulto , Biomarcadores , Biopsia , Humanos , Hígado/patología , Persona de Mediana Edad , Recurrencia , Presión Venosa
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