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1.
Clin Infect Dis ; 72(2): 202-211, 2021 01 27.
Artículo en Inglés | MEDLINE | ID: mdl-31912157

RESUMEN

BACKGROUND: Hepatitis B virus RNA (HBV-RNA) is a novel serum biomarker that correlates with transcription of intrahepatic covalently closed circular (cccDNA), which is an important target for pegylated interferon (PEG-IFN) and novel therapies for functional cure. We studied HBV-RNA kinetics following PEG-IFN treatment and its potential role as a predictor to response in HBeAg-negative chronic hepatitis B (CHB) patients. METHODS: HBV-RNA levels were measured in 133 HBeAg-negative CHB patients treated in an international randomized controlled trial (PARC study). Patients received PEG-IFN α-2a for 48 weeks. HBV-RNA was measured from baseline through week 144. Response was defined as HBV-DNA <2000 IU/mL and ALT normalization at week 72. Kinetics of HBV-RNA were compared with HBV-DNA, HBsAg, and HBcrAg. RESULTS: Mean HBV-RNA at baseline was 4.4 (standard deviation [SD] 1.2) log10 c/mL. At week 12, HBV-RNA declined by -1.6 (1.1) log10 c/mL. HBV-RNA showed a greater decline in responders compared to nonresponders early at week 12 (-2.0 [1.2] vs -1.5 [1.1] log10 c/mL, P = .04). HBV-RNA level above 1700 c/mL (3.2 log10 c/mL) had a negative predictive value of 91% at week 12 and 93% at week 24 (P = .01) for response. Overall, HBV-RNA showed a stronger correlation with HBV-DNA and HBcrAg (.82 and .80, P < .001) and a weak correlation with HBsAg (.25). At week 12, HBV-RNA was significantly lower among patients with lower HBsAg (<100 IU/mL) or HBsAg loss at week 144. CONCLUSIONS: During PEG-IFN treatment for HBeAg-negative CHB, HBV-RNA showed a fast and significant decline that correlates with treatment response and HBsAg loss at long-term follow-up. CLINICAL TRIALS REGISTRATION: NCT00114361.


Asunto(s)
Antivirales/uso terapéutico , Virus de la Hepatitis B , Hepatitis B Crónica , Interferón-alfa/uso terapéutico , Antígenos de Superficie de la Hepatitis B , Antígenos e de la Hepatitis B , Virus de la Hepatitis B/genética , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/tratamiento farmacológico , Humanos , Polietilenglicoles/uso terapéutico , ARN Viral/análisis , Proteínas Recombinantes/uso terapéutico
2.
J Hepatol ; 74(2): 283-292, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32931877

RESUMEN

BACKGROUND & AIMS: During treatment of chronic HBV infections, loss or seroconversion of the HBV surface antigen (HBsAg) is considered a functional cure. HBsAg consists of the large (LHBs), middle (MHBs), and small surface protein (SHBs) and their relative proportions correlate strongly with disease stage. Our aim was to assess the association between HBsAg composition and functional cure during treatment. METHODS: A total of 83 patients were retrospectively analyzed. HBsAg loss was achieved by 17/64 patients during nucleos(t)ide analogue (NA) treatment and 3/19 patients following treatment with pegylated interferon-alfa2a (PEG-IFN) for 48 weeks. Sixty-three patients without HBsAg loss were matched as controls. LHBs, MHBs and SHBs were quantified in sera collected before and during treatment. RESULTS: Before treatment, median MHBs levels were significantly lower in patients with subsequent HBsAg loss than in those without (p = 0.005). During treatment, MHBs and LHBs proportions showed a fast decline in patients with HBsAg loss, but not in patients with HBV e antigen seroconversion only or patients without serologic response. MHBs became undetectable by month 6 of NA treatment in all patients with HBsAg loss, which occurred on average 12.8 ± 8.7 (0-52) months before loss of total HBsAg. Receiver-operating characteristic analyses revealed that the proportion of MHBs was the best early predictor of HBsAg loss before NA treatment (AUC = 0.726, p = 0.019). In patients achieving HBsAg loss with PEG-IFN, the proportions of MHBs and LHBs showed similar kinetics. CONCLUSION: Quantification of HBsAg proteins shows promise as a novel tool to predict early treatment response. These assessments may help optimize individual antiviral treatment, increasing the rates of functional cure in chronically HBV-infected patients. LAY SUMMARY: The hepatitis B surface antigen (HBsAg) is a key serum marker for viral replication. Loss of HBsAg is considered stable remission, which can be achieved with antiviral treatments. We have investigated whether the ratios of the different components of HBsAg, namely the large (LHBs) and medium (MHBs) HBsAg during different treatments are associated with the occurrence of HBsAg loss. We found that LHBs and MHBs decrease earlier than total HBsAg before HBsAg loss and we propose LHBs and MHBs as promising novel biomarker candidates for predicting cure of HBV infection.


Asunto(s)
Antígenos de Superficie de la Hepatitis B , Virus de la Hepatitis B , Hepatitis B Crónica , Seroconversión/efectos de los fármacos , Antígenos de Superficie/análisis , Antígenos de Superficie/aislamiento & purificación , Antivirales/administración & dosificación , Biomarcadores Farmacológicos/sangre , Femenino , Antígenos de Superficie de la Hepatitis B/análisis , Antígenos de Superficie de la Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/inmunología , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/inmunología , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/sangre , Hepatitis B Crónica/diagnóstico , Hepatitis B Crónica/tratamiento farmacológico , Hepatitis B Crónica/virología , Humanos , Interferón-alfa/administración & dosificación , Masculino , Persona de Mediana Edad , Nucleósidos/administración & dosificación , Gravedad del Paciente , Polietilenglicoles/administración & dosificación , Valor Predictivo de las Pruebas , Proteínas Recombinantes/administración & dosificación , Estudios Retrospectivos , Proteínas Virales/análisis , Proteínas Virales/aislamiento & purificación
3.
J Viral Hepat ; 27(6): 610-619, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-32052503

RESUMEN

Hepatitis B virus (HBV) RNA in serum is a novel biomarker that reflects cccDNA activity. We investigated whether HBV RNA can predict serological response to peginterferon (PEG-IFN) treatment. Serum HBV RNA levels were retrospectively measured at weeks 0, 12, 24 and 52 of therapy and after treatment discontinuation (week 78) in 266 HBeAg-positive chronic HBV patients who had participated in a global randomized controlled trial (HBV99-01 study). Patients received 52 weeks PEG-IFN monotherapy (n = 136) or PEG-IFN and lamivudine (n = 130). The primary end point was HBeAg loss 24 weeks after PEG-IFN discontinuation. At baseline, the mean serum level of HBV RNA was 6.8 (SD 1.2) log c/mL. HBV RNA levels declined to 4.7 (1.7) log c/mL after one year of PEG-IFN therapy alone and to 3.3 (1.2)log c/mL after combination therapy. From week 12 onward, HBV RNA level was significantly lower in patients who achieved HBeAg loss at the end of follow-up as compared to those who did not, regardless of treatment allocation (week 12:4.4 vs 5.1 log c/mL, P = .01; week 24:3.7 vs 4.9 log c/mL, P < .001). The performance of a multivariable model based on HBV RNA level was comparable at week 12 (AUC 0.68) and 24 (AUC 0.72) of therapy. HBV RNA level above 5.5 log c/mL at week 12 showed negative predictive values of 93/67/90/64% for HBV genotypes A/B/C/D for the prediction of HBeAg loss. In conclusion, HBV RNA in serum declines profoundly during PEG-IFN treatment. Early on-treatment HBV RNA level may be used to predict nonresponse.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis B Crónica , Interferón-alfa/uso terapéutico , ARN Viral/sangre , Adulto , Femenino , Antígenos e de la Hepatitis B , Virus de la Hepatitis B/genética , Hepatitis B Crónica/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Polietilenglicoles/uso terapéutico , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
4.
J Infect Dis ; 218(7): 1066-1074, 2018 08 24.
Artículo en Inglés | MEDLINE | ID: mdl-29741634

RESUMEN

Background: Hepatitis B virus (HBV) RNA is a novel serum biomarker that has the potential to predict treatment response in patients with chronic hepatitis B. We explored whether HBV RNA serum levels can predict hepatitis B e antigen (HBeAg) seroconversion in patients treated with peginterferon alfa-2a. Methods: Serum samples from HBeAg-positive patients previously treated with peginterferon alfa-2a in 2 large randomized controlled trials were retrospectively analyzed. HBV RNA levels were measured using a real-time polymerase chain reaction assay. Ability of individual biomarkers to predict HBeAg seroconversion at 24 weeks posttreatment was evaluated using receiver operating characteristics (ROC) analyses. Results: The study included 131 subjects (70% male, 96% Asians, 35% HBV genotypes B, and 61% C), 76 treated with peginterferon alfa-2a alone and 55 in combination with lamivudine. Median HBV RNA levels were significantly lower, at all timepoints, in patients achieving HBeAg seroconversion. Levels of HBV RNA at treatment weeks 12 and 24 showed good ability to predict HBeAg seroconversion (area under ROC scores >0.75, P < .001). A HBV RNA cutoff of >5.5 log10 copies/mL identified 30% of nonresponders at week 12 (negative predictive value >90%). Conclusion: Serum HBV RNA is an early predictor of HBeAg seroconversion in patients treated with peginterferon alfa-2a. Clinical Trials Registration: NCT01705704.


Asunto(s)
Antivirales/uso terapéutico , Antígenos e de la Hepatitis B/sangre , Virus de la Hepatitis B/inmunología , Hepatitis B Crónica/tratamiento farmacológico , Interferón-alfa/uso terapéutico , Polietilenglicoles/uso terapéutico , Adulto , Biomarcadores/análisis , Femenino , Virus de la Hepatitis B/efectos de los fármacos , Virus de la Hepatitis B/genética , Hepatitis B Crónica/virología , Humanos , Masculino , ARN Viral/sangre , Proteínas Recombinantes/uso terapéutico , Estudios Retrospectivos , Seroconversión , Adulto Joven
5.
Hepatology ; 68(3): 839-847, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29514389

RESUMEN

Hepatitis B virus (HBV) RNA in serum is a novel biomarker for intrahepatic HBV replication and treatment response. For its proper use, it is essential to identify factors influencing serum HBV RNA level. Using a rapid amplification of complimentary DNA (cDNA) ends (RACE) PCR technique (lower limit of detection [LLD], 800 copies/mL [c/mL]), serum HBV RNA levels were measured in samples of 488 untreated individuals with chronic HBV infection who were eligible to treatment according to currently used recommendations. We explored the association of serum levels of HBV RNA with patient- and virus-associated factors. HBV genotype distribution was 21/10/20/46/3% for A/B/C/D/other. Mean HBV RNA serum level was 5.9 (1.6) log10 c/mL (hepatitis B e antigen [HBeAg]-positive chronic hepatitis B [CHB], 6.5 [1.2] log c/mL; HBeAg-negative CHB, 4.1 [1.2] log c/mL; P < 0.001). By multivariable linear regression, factors associated with lower HBV RNA level were HBeAg negativity (ß = -0.69; P < 0.001), HBV genotypes A (ß = -0.13; P = 0.002), B (ß = -0.07; P = 0.049), and C (ß = -0.61; P < 0.001) in comparison to D, and presence of HBV basal core promoter mutation either alone (ß = -0.14; P = 0.001) or in combination with precore mutation (ß = -0.22; P < 0.001). Higher serum alanine aminotransferase (ALT) was associated with higher HBV RNA (ß = 0.23; P < 0.001). HBV RNA correlated strongly with HBV DNA (HBeAg-pos, r = 0.72; P < 0.001; HBeAg-neg, r = 0.78; P < 0.001) and moderately with quantitative hepatitis B surface antigen (qHBsAg; HBeAg-pos, r = 0.54; P < 0.001; HBeAg-neg, r = 0.19; P = 0.04) and quantitative hepatitis B surface antigen (qHBeAg; r = 0.41; P < 0.001). CONCLUSION: In this multiethnic cohort of 488 untreated individuals with CHB, factors associated with serum HBV RNA level were HBeAg status, serum ALT, HBV genotype, and presence of basal core promotor mutations. For the future use of serum HBV RNA as a clinical marker, it seems mandatory to take these factors into consideration. (Hepatology 2018).


Asunto(s)
Virus de la Hepatitis B/genética , Hepatitis B Crónica/sangre , Hepatitis B Crónica/virología , Interacciones Microbiota-Huesped , ARN Viral/sangre , Adulto , Femenino , Humanos , Masculino , Análisis de Regresión
6.
Gut ; 67(11): 2045-2053, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-28951526

RESUMEN

OBJECTIVE: Among individuals with chronic hepatitis B, those with hepatitis B e-antigen (HBeAg)-negative chronic hepatitis (CHB) can be difficult to distinguish from those with HBeAg-negative chronic HBV infection, also referred to as inactive HBV carriers (ICs), but both require different medical management. The level of HBV surface antigen (HBsAg) has been proposed as a marker to discriminate between chronic infection and hepatitis stages. HBsAg consists of large, middle and small HBs. The aim of this study was to determine whether the composition of HBsAg improved the identification of ICs among HBsAg-positive subjects with different phases of HBV infections. DESIGN: HBV large surface proteins (LHBs) and HBV middle surface proteins (MHBs) were quantified in serum samples from 183 clinically well-characterised untreated patients with acute (n=14) HBV infection, ICs (n=44), CHBs (n=46), chronic HBeAg-positive phase (n=68) and hepatitis delta coinfection (n=11) using an ELISA, with well-defined monoclonal antibodies against the preS1 domain (LHBs) and the preS2-domain (MHBs). A Western blot analysis was used to verify the quantitation of the components of HBsAg. Total HBsAg was quantified using a modified commercially available assay (HBsAg V.6.0, Enzygnost, Siemens, Erlangen). RESULTS: The composition of HBsAg showed specific patterns across different phases of hepatitis B. Individuals in the IC phase had significantly lower proportions of LHBs and MHBs than patients in acute or chronic phases irrespective of their HBV e-antigen status (p<0.0001) or HBsAg level. Both LHBs and MHBs ratios better predicted the IC phase than total HBsAg levels. CONCLUSION: Quantification of MHBs, particularly LHBs represents a novel tool for the identification of the IC stage.


Asunto(s)
Biomarcadores/sangre , Portador Sano/sangre , Antígenos de Superficie de la Hepatitis B/sangre , Virus de la Hepatitis B/genética , Hepatitis B/virología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Western Blotting , ADN Viral/sangre , Ensayo de Inmunoadsorción Enzimática , Femenino , Hepatitis B/sangre , Antígenos de Superficie de la Hepatitis B/química , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto Joven
7.
Gut ; 66(10): 1829-1837, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-27196570

RESUMEN

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.


Asunto(s)
Hepatitis C Crónica/genética , Interleucinas/genética , ARN Mensajero/sangre , Receptor Toll-Like 9/genética , Adulto , Anciano , Alelos , Progresión de la Enfermedad , Femenino , Regulación de la Expresión Génica/genética , Alemania , Haplotipos , Humanos , Irlanda , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , Remisión Espontánea , Estudios Retrospectivos , Factores Sexuales , Suiza , Transcripción Genética
8.
Nat Struct Mol Biol ; 17(11): 1367-76, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20972448

RESUMEN

Classic nuclear export signals (NESs) confer CRM1-dependent nuclear export. Here we present crystal structures of the RanGTP-CRM1 complex alone and bound to the prototypic PKI or HIV-1 Rev NESs. These NESs differ markedly in the spacing of their key hydrophobic (Φ) residues, yet CRM1 recognizes them with the same rigid set of five Φ pockets. The different Φ spacings are compensated for by different conformations of the bound NESs: in the case of PKI, an α-helical conformation, and in the case of Rev, an extended conformation with a critical proline docking into a Φ pocket. NMR analyses of CRM1-bound and CRM1-free PKI NES suggest that CRM1 selects NES conformers that pre-exist in solution. Our data lead to a new structure-based NES consensus, and explain why NESs differ in their affinities for CRM1 and why supraphysiological NESs bind the exportin so tightly.


Asunto(s)
Transporte Activo de Núcleo Celular/fisiología , Carioferinas/química , Señales de Exportación Nuclear , Receptores Citoplasmáticos y Nucleares/química , Proteína de Unión al GTP ran/química , Sitios de Unión , Secuencia de Consenso , Cristalografía por Rayos X , Péptidos y Proteínas de Señalización Intracelular/química , Péptidos y Proteínas de Señalización Intracelular/metabolismo , Carioferinas/genética , Modelos Moleculares , Datos de Secuencia Molecular , Resonancia Magnética Nuclear Biomolecular , Mutación Puntual , Estructura Terciaria de Proteína , Receptores Citoplasmáticos y Nucleares/genética , Productos del Gen rev del Virus de la Inmunodeficiencia Humana/química , Productos del Gen rev del Virus de la Inmunodeficiencia Humana/metabolismo , Proteína Exportina 1
9.
Hepatology ; 41(6): 1225-32, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15880568

RESUMEN

The most striking phenomenon of glutamine synthetase (GS) expression in the liver is its unique restriction to cells surrounding the terminal hepatic venules. Expression is positively regulated by elements located in the 5'-upstream region and in the first intron of the gene. It was long believed that transcription factors present in GS-positive cells and absent in GS-negative cells are responsible for the phenomenon of zonal expression. However, strong enhancers are equally active in both types of cells. Therefore, the existence of a silencer mechanism in GS-negative hepatocytes was postulated. In the present study, a GS silencer element was investigated that was previously identified within the first intron and was shown to be able to prevent glucocorticoid-induced expression in cells negative for a transacting factor designated GS silencer element-binding protein. Reporter gene assays with the silencer element in combination with the most potent 5'-enhancer of the GS gene demonstrate that the silencer element is able to prevent enhancement mediated by the 5'-enhancer in combination with a heterologous as well as with the homologous promoter. More importantly, the effect of the silencer is shown to be restricted to GS-negative hepatocytes. In conclusion, the phenomenon of zonal expression of GS in the liver is caused by a protein present in GS-negative cells and absent in GS-positive cells that interacts with the silencer element in the first intron and not by a differential expression of enhancer-binding proteins.


Asunto(s)
Glutamato-Amoníaco Ligasa/metabolismo , Intrones , Hígado/enzimología , Elementos Silenciadores Transcripcionales , Animales , Elementos de Facilitación Genéticos , Expresión Génica , Genes Reporteros , Hepatocitos/metabolismo , Masculino , Regiones Promotoras Genéticas , Ratas , Ratas Sprague-Dawley , Distribución Tisular
10.
Forensic Sci Int ; 129(2): 99-103, 2002 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-12243877

RESUMEN

X-linked DNA markers are increasingly used in forensic kinship testing. This paper presents sequencing data of the short tandem repeats (STRs) DXS9895, DXS8378, DXS7132, DXS6800, DXS7133, GATA172D05, DXS7423, DXS8377 and proposes an allele nomenclature. Alleles were assigned according to the recommendations of the International Society of Forensic Genetics (ISFG) Commission.


Asunto(s)
Cromosomas Humanos X/genética , Secuencias Repetidas en Tándem/genética , Alelos , Marcadores Genéticos/genética , Genética de Población , Alemania , Humanos , Reacción en Cadena de la Polimerasa , Terminología como Asunto
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