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1.
Immunity ; 42(1): 123-32, 2015 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-25557055

RESUMEN

Host innate recognition triggers key immune responses for viral elimination. The sensing mechanism of hepatitis B virus (HBV), a DNA virus, and the subsequent downstream signaling events remain to be fully clarified. Here we found that type III but not type I interferons are predominantly induced in human primary hepatocytes in response to HBV infection, through retinoic acid-inducible gene-I (RIG-I)-mediated sensing of the 5'-ε region of HBV pregenomic RNA. In addition, RIG-I could also counteract the interaction of HBV polymerase (P protein) with the 5'-ε region in an RNA-binding dependent manner, which consistently suppressed viral replication. Liposome-mediated delivery and vector-based expression of this ε region-derived RNA in liver abolished the HBV replication in human hepatocyte-chimeric mice. These findings identify an innate-recognition mechanism by which RIG-I dually functions as an HBV sensor activating innate signaling and to counteract viral polymerase in human hepatocytes.


Asunto(s)
Productos del Gen pol/antagonistas & inhibidores , Virus de la Hepatitis B/fisiología , Hepatitis B Crónica/inmunología , Hepatocitos/fisiología , Hígado/fisiología , Proteínas de la Membrana/metabolismo , Proteínas del Tejido Nervioso/metabolismo , ARN Viral/inmunología , Animales , Preescolar , Femenino , Células Hep G2 , Hepatocitos/trasplante , Hepatocitos/virología , Humanos , Inmunidad Innata , Interferones/metabolismo , Hígado/virología , Proteínas de la Membrana/inmunología , Ratones , Ratones SCID , Proteínas del Tejido Nervioso/inmunología , ARN Viral/genética , Receptores de Superficie Celular , Transgenes/genética , Quimera por Trasplante , Replicación Viral/genética
2.
Artículo en Inglés | MEDLINE | ID: mdl-38943340

RESUMEN

BACKGROUND AND AIM: Serum interleukin-6 (IL-6) before the administration of atezolizumab plus bevacizumab (Atez + Bev) is a prognostic biomarker in patients with hepatocellular carcinoma (HCC) treated with Atez + Bev. We previously revealed that the neutrophil-to-lymphocyte ratio and serum chemokine levels during treatment with Atez + Bev were more useful as prognostic biomarkers. Therefore, we examined the predictive ability of serum IL-6 for the efficacy of Atez + Bev in patients with HCC. METHODS: We enrolled 94 patients with HCC who received treatment with Atez + Bev. Initial responses were assessed through dynamic computed tomography or magnetic resonance imaging. The levels of IL-6 in serum were measured before and at the initiation of the second course of Atez + Bev. Subsequently, the relationship of IL-6 levels with treatment efficacy was evaluated. RESULTS: IL-6 levels at the initiation of the second course tended to be higher in patients with progressive disease versus those with non-progressive disease in the initial evaluation (P = 0.054). Moreover, the cutoff value (7.4 pg/mL) was useful in stratifying patients by overall survival (i.e. low vs high: not reached vs 21.4 months, respectively, P = 0.001) and progression-free survival (low vs high: 11.9 vs 5.2 months, respectively, P = 0.004). This result was reproduced in patients with HCC who received Atez + Bev as first-line therapy. In the multivariate analyses, IL-6 levels at the initiation of the second course were independent predictive factors for progression-free and overall survival. CONCLUSIONS: Serum levels of IL-6 at the initiation of the second course of treatment may predict Atez + Bev efficacy and prognosis in HCC.

3.
Mol Biol Rep ; 49(1): 403-412, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34716866

RESUMEN

BACKGROUND: Hepatitis B Virus (HBV) is the most common cause of chronic liver disease worldwide. The mechanisms that regulate HBV viral replication remain poorly defined. Here, we show that blocking of the neddylation elicits antiviral effect against HBV replication, indicating that NEDD8 supports viral production. METHODS AND RESULTS: To explore role of neddylation, HBV-replicating HepG2.2.15.7 cells and HBV-infected HepG2-hNTCP-30 cells were treated with siNEDD8 and MLN4924, a potent and selective NEDD8-activating enzyme inhibitor. Cell viability, intracellular and extracellular HBV DNA, covalently closed circular DNA (cccDNA), HBsAg, HBeAg, and HBcrAg were measured to assess the consequences of the various treatments on viral replication. Our data showed that HBV infection increased NEDD8 expression in human liver cell lines. Symmetrically, NEDD8 knockdown by siRNA or MLN4924 treatments decreased HBV replication in HepG2.2.15.7 and HepG2-hNTCP-30 cells. Notably, HBsAg, and HBeAg secretions were strongly suppressed in the culture supernatants, but not the HBcrAg. These results indicate that the suppression of NEDD8 decreases HBV replication. However, cccDNA steady level confirms once again its persistence and longevity in chronic infection. CONCLUSION: The manipulation of the neddylation pathway can thus provide new tools interfering with HBV persistence as well as novel therapeutic strategies against chronic hepatitis B.


Asunto(s)
Antivirales/farmacología , Ciclopentanos/farmacología , Virus de la Hepatitis B/fisiología , Proteína NEDD8/metabolismo , Pirimidinas/farmacología , ARN Interferente Pequeño/farmacología , Supervivencia Celular/efectos de los fármacos , ADN Viral/genética , Regulación de la Expresión Génica/efectos de los fármacos , Células Hep G2 , Antígenos de Superficie de la Hepatitis B/genética , Antígenos e de la Hepatitis B/genética , Virus de la Hepatitis B/efectos de los fármacos , Humanos , Proteína NEDD8/genética , Replicación Viral/efectos de los fármacos
4.
Hepatology ; 69(1): 19-33, 2019 01.
Artículo en Inglés | MEDLINE | ID: mdl-29893492

RESUMEN

Hepatitis B virus (HBV) genotype F1b infection is strongly associated with hepatocellular carcinoma (HCC) in young Alaskan Native (AN) people. However, the mechanisms by which genotype F1b causes HCC are unclear. Here, we analyzed the clinical and virological significance of genotype F1b in long-term serial samples from 20 HCC patients with HBV infection. Complete sequence analyses revealed that all isolates were genotype F1b. In the HCC patients, T1938C and A2051C mutations in the core region had accumulated significantly with A1762T/G1764A mutations in the basal core promoter (BCP) region and G1896A mutation in the precore (PC) region. Several HBV clones containing the core mutations were examined for their replication efficiency and core stability in vitro. Clones containing the A2051C mutation replicated more efficiently than the wild type in association with enhanced stability of core protein dimerization. In chimeric mice with human hepatocytes carrying BCP/PC/2051 mutant but not with wild-type virus, liver fibrosis was induced in association with high levels of serum HBV DNA and hepatitis B surface antigen. Interestingly, microarray analysis and validation study showed that five genes associated with cell proliferation or carcinogenesis, v-myc avian myelocytomatosis viral oncogene homolog, Grb2-associated binding protein 2, bradykinin receptor B2, follistatin, and mitogen-activated protein kinase kinase kinase 8, were significantly up-regulated in human hepatocytes infected with genotype F1b, particularly the BCP/PC/2051 mutant, compared with other genotypes. Conclusion: We have identified an association between Alaska-specific core mutations and HCC development in AN people infected with genotype F1b; accumulation of these core mutations during the course of chronic infection with genotype F1b would contribute to HCC development in AN people earlier in life.


Asunto(s)
Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/virología , Genotipo , Virus de la Hepatitis B/genética , Hepatitis B Crónica/complicaciones , Pueblos Indígenas , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/virología , Adolescente , Adulto , Anciano , Alaska , Niño , Preescolar , Virus de la Hepatitis B/clasificación , Humanos , Lactante , Persona de Mediana Edad , Mutación , Adulto Joven
5.
Artículo en Inglés | MEDLINE | ID: mdl-30670420

RESUMEN

We designed, synthesized, and characterized a novel nucleoside analog, (1S,3S,5S)-3-(2-amino-6-oxo-1,6-dihydro-9H-purin-9-yl)-5-hydroxy-1-(hydroxymethyl)-2-methylene-cyclopentanecarbonitrile, or 4'-cyano-methylenecarbocyclic-2'-deoxyguanosine (CMCdG), and evaluated its anti-hepatitis B virus (anti-HBV) activity, safety, and related features. CMCdG's in vitro activity was determined using quantitative PCR and Southern blotting assays, and its cytotoxicity was determined with a 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay, while its in vivo activity and safety were determined in human liver-chimeric mice infected with wild-type HBV genotype Ce (HBVWTCe) and an entecavir (ETV)-resistant HBV variant containing the amino acid substitutions L180M, S202G, and M204V (HBVETV-RL180M/S202G/M204V). CMCdG potently inhibited HBV production in HepG2.2.15 cells (50% inhibitory concentration [IC50], ∼30 nM) and HBVWTCe plasmid-transfected Huh7 cells (IC50, 206 nM) and efficiently suppressed ETV-resistant HBVETV-RL180M/S202G/M204V (IC50, 2,657 nM), while it showed no or little cytotoxicity (50% cytotoxic concentration, >500 µM in most hepatocytic cells examined). Two-week peroral administration of CMCdG (1 mg/kg of body weight/day once a day [q.d.]) to HBVWTCe-infected human liver-chimeric mice reduced the level of viremia by ∼2 logs. CMCdG also reduced the level of HBVETV-RL180M/S202G/M204V viremia by ∼1 log in HBVETV-RL180M/S202G/M204V-infected human liver-chimeric mice, while ETV (1 mg/kg/day q.d.) completely failed to reduce the viremia. None of the CMCdG-treated mice had significant drug-related changes in body weights or serum human albumin levels. Structural analyses using homology modeling, semiempirical quantum methods, and molecular dynamics revealed that although ETV triphosphate (TP) forms good van der Waals contacts with L180 and M204 of HBVWTCe reverse transcriptase (RT), its contacts with the M180 substitution are totally lost in the HBVETV-RL180M/S202G/M204V RT complex. However, CMCdG-TP retains good contacts with both the HBVWTCe RT and HBVETV-RL180M/S202G/M204V RT complexes. The present data warrant further studies toward the development of CMCdG as a potential therapeutic for patients infected with drug-resistant HBV and shed light on the further development of more potent and safer anti-HBV agents.


Asunto(s)
Antivirales/farmacología , Virus de la Hepatitis B/efectos de los fármacos , Hepatitis B/tratamiento farmacológico , Nucleósidos/farmacología , Purinas/farmacología , Inhibidores de la Transcriptasa Inversa/farmacología , Animales , Antivirales/efectos adversos , Línea Celular Tumoral , Replicación del ADN/efectos de los fármacos , Descubrimiento de Drogas , Farmacorresistencia Viral , Guanina/análogos & derivados , Guanina/farmacología , Células Hep G2 , Humanos , Ratones , Nucleósidos/efectos adversos , Purinas/efectos adversos , Inhibidores de la Transcriptasa Inversa/efectos adversos , Albúmina Sérica/análisis
6.
J Med Virol ; 89(2): 257-266, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27458715

RESUMEN

The objective of this study was to determine the prevalence of co-infection with hepatitis B virus (HBV) and human immunodeficiency virus (HIV) and the genetic characteristics of both viruses among pre-HIV-treatment patients in Harare, Zimbabwe. This cross-sectional survey involved 176 remnant plasma samples collected from consenting HIV patients (median age 35 [18-74]) between June and September 2014. HBV seromarkers were determined by high-sensitivity chemiluminescence assays. Molecular evolutionary analyses were conducted on the basal core promoter/precore (BCP/PC) and S regions of HBV, as well as part of the HIV pol region. Of the 176 participants (65.7% female), 19 (10.8%) were positive for HBsAg (median 0.033 IU/ml (IQR 0.01-415). The HBsAg incidence was higher in men than women (P = 0.009). HBsAg-positive subjects had lower median CD4 counts (P = 0.016). HBV DNA was detectable in 12 HBsAg-positive samples (median 3.36 log cp/ml (2.86-4.51), seven being amplified and sequenced. All isolates were subgenotype A1 without HBV drug resistance mutations but each had at least one BCP/PC mutation. PreS deletion mutants and small S antigen variants M133I/T and D144G were identified. Of the 164 HIV isolates successfully genotyped, 163 (99.4%) were HIV-1 subtype C and only one was HIV-1 subtype F1. Sixteen (9.8%) had at least one drug resistance mutation, predominantly non-nucleoside reverse transcriptase inhibitor-related mutations, observed mostly among female participants. This study shows that co-infection with HBV is present among HIV patients enrolling into HIV care in Zimbabwe, suggesting that HBV screening and monitoring programmes be strengthened in this context. J. Med. Virol. 89:257-266, 2017. © 2016 Wiley Periodicals, Inc.


Asunto(s)
Coinfección/epidemiología , Coinfección/virología , Infecciones por VIH/epidemiología , VIH/clasificación , Virus de la Hepatitis B/clasificación , Hepatitis B Crónica/epidemiología , Adolescente , Adulto , Anciano , Estudios Transversales , Femenino , Genotipo , VIH/genética , VIH/aislamiento & purificación , Infecciones por VIH/complicaciones , Infecciones por VIH/virología , Antígenos del Núcleo de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Virus de la Hepatitis B/aislamiento & purificación , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/virología , Humanos , Incidencia , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Mutación , Adulto Joven , Zimbabwe/epidemiología , Productos del Gen pol del Virus de la Inmunodeficiencia Humana/genética
7.
Liver Int ; 37(8): 1138-1147, 2017 08.
Artículo en Inglés | MEDLINE | ID: mdl-27992664

RESUMEN

BACKGROUND & AIMS: Occult hepatitis B virus (HBV) infection should be evaluated before systemic chemotherapy to prevent HBV reactivation-related hepatitis. We investigated HBV reactivation using high sensitivity HB surface antigen (HBsAg) chemiluminescent enzyme immunoassay (HBsAg-HQ) and ultra-high sensitive HBsAg assay employing a semi-automated immune complex transfer chemiluminescence enzyme technique (ICT-CLEIA). METHODS: Of 120 HBV-resolved patients with haematological malignancy receiving systemic chemotherapy from 2012 to 2015 in our hospital, 13 patients had HBV DNA reactivation (in 12/13 patients HBV DNA became quantifiable) according to HBV DNA monitoring. These patients were applied for Architect HBsAg-QT (detection limit:50 mIU/mL), HBsAg-HQ (5 mIU/mL) and ICT-CLEIA (0.5 mIU/mL) using stored samples. RESULTS: When HBV DNA was firstly quantifiable by regular HBV DNA monitoring, HBsAg-QT was detected in 1/12 patients (8%), HBsAg-HQ was detected in 4/12 patients (33%) and ICT-CLEIA was detected in all 12 patients (100%), suggesting that the sensitivity of ICT-CLEIA was comparable to that of HBV DNA quantification. Interestingly, two patients were HBsAg positive by ICT-CLEIA before HBV DNA became detectable. Median difference of detectable point between HBV DNA and ICT-CLEIA was zero (range from -28 to 56 days), while median delay by HBsAg-QT or HBsAg-HQ was 52.5 days after HBV DNA became detectable. Although anti-HBs titres were high (131.9 mIU, 80.4 mIU) in two patients with escape mutations (Saa126V, Saa145R), HBsAg by ICT-CLEIA and HBV DNA were detectable concurrently. CONCLUSIONS: ICT-CLEIA is a novel assay for HBV monitoring to prevent hepatitis caused by HBV reactivation.


Asunto(s)
Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B/diagnóstico , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Hepatitis B/inmunología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia
8.
J Hepatol ; 64(3): 547-55, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26505121

RESUMEN

BACKGROUND & AIMS: Antiviral agents including entecavir (ETV) suppress the replication of the hepatitis B virus (HBV) genome in human hepatocytes, but they do not reduce the abundance of viral proteins. The present study focused on effectively reducing viral protein levels. METHODS: We designed siRNAs (HBV-siRNA) that target consensus sequences in HBV genomes. To prevent the emergence of escaped mutant virus, we mixed three HBV-siRNAs (HBV-siRNAmix); the mixture was encapsulated in a novel pH-sensitive multifunctional envelope-type nanodevice (MEND), a hepatocyte-specific drug delivery system. Coagulation factor 7 siRNA was used to assess delivery and knockdown efficiencies of MEND/siRNA treatments in mice. The potency of MEND/HBV-siRNAmix was evaluated in primary human hepatocytes and in chimeric mice with humanized liver persistently infected with HBV. RESULTS: Effective knockdown of targets, efficient delivery of siRNA, and liver-specific delivery were each observed with MEND. MEND/HBV-siRNA caused efficient reduction of HBsAg and HBeAg in vitro and in vivo. However, ETV treatment did not efficiently reduce HBsAg or HBeAg when compared with a single MEND/HBV-siRNAmix treatment. Furthermore, the suppressive effects of a single dose of MEND/HBV-siRNAmix persisted for 14days in vitro and in vivo. CONCLUSION: We demonstrated that MEND/HBV-siRNA controlled HBV more efficiently than did ETV. Furthermore, the effect of a single dose of MEND/HBV-siRNA persisted for a long time. These results indicated that MEND/HBV-siRNA may be a promising novel HBV treatment that is more effective than reverse transcriptase inhibitors.


Asunto(s)
Técnicas de Transferencia de Gen , Hepatitis B Crónica/terapia , ARN Interferente Pequeño/administración & dosificación , Animales , ADN Viral/análisis , Antígenos de Superficie de la Hepatitis B/análisis , Antígenos e de la Hepatitis B/análisis , Virus de la Hepatitis B/genética , Humanos , Concentración de Iones de Hidrógeno , Liposomas , Ratones
9.
Biochem Biophys Res Commun ; 469(2): 229-35, 2016 Jan 08.
Artículo en Inglés | MEDLINE | ID: mdl-26654952

RESUMEN

The northern treeshrew (Tupaia belangeri) has been reported to be an effective candidate for animal infection model with hepatitis B virus (HBV). The objective of our study was to analyze the growth characteristics of HBV in tupaia hepatocytes and the host response to HBV infection. We established primary tupaia hepatocytes (3-6-week old tupaia) and infected them with HBV genotypes A, B and C, and all the genotypes proliferated as well as those in human primary hepatocytes (>10(5) copies/ml in culture supernatant). We next generated a chimeric mouse with tupaia liver by transplantation of tupaia primary hepatocytes to urokinase-type plasminogen activator cDNA (cDNA-uPA)/severe combined immunodeficient (SCID) mice and the replacement ratio with tupaia hepatocytes was found to be more than 95%. Infection of chimeric mice with HBV (genotypes B, C, and D) resulted in HBV-DNA level of 10(4)-10(6) copies/ml after 8 weeks of infection, which were almost similar to that in humanized chimeric mouse. In contrast, serum HBV level in adult tupaia (1-year-old tupaia) was quite low (<10(3) copies/ml). Understanding the differences in the response to HBV infection in primary tupaia hepatocytes, chimeric mouse, and adult tupaia will contribute to elucidating the mechanism of persistent HBV infection and viral eradication. Thus, T. belangeri was found to be efficient for studying the host response to HBV infection, thereby providing novel insight into the pathogenesis of HBV.


Asunto(s)
Virus de la Hepatitis B/fisiología , Hepatitis B/virología , Hepatocitos/virología , Tupaia/virología , Replicación Viral/fisiología , Animales , Ratones
10.
Hepatology ; 62(4): 1024-36, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26122273

RESUMEN

UNLABELLED: Certain nucleoside/nucleotide reverse transcriptase (RT) inhibitors (NRTIs) are effective against human immunodeficiency virus type 1 (HIV-1) and hepatitis B virus (HBV). However, both viruses often acquire NRTI resistance, making it crucial to develop more-potent agents that offer profound viral suppression. Here, we report that 4'-C-cyano-2-amino-2'-deoxyadenosine (CAdA) is a novel, highly potent inhibitor of both HBV (half maximal inhibitory concentration [IC50 ] = 0.4 nM) and HIV-1 (IC50 = 0.4 nM). In contrast, the approved anti-HBV NRTI, entecavir (ETV), potently inhibits HBV (IC50 = 0.7 nM), but is much less active against HIV-1 (IC50 = 1,000 nM). Similarly, the highly potent HIV-1 inhibitor, 4'-ethynyl-2-fluoro-2'-deoxyadenosine (EFdA; IC50 = 0.3 nM) is less active against HBV (IC50 = 160 nM). Southern analysis using Huh-7 cells transfected with HBV-containing plasmids demonstrated that CAdA was potent against both wild-type (IC50 = 7.2 nM) and ETV-resistant HBV (IC50 = 69.6 nM for HBVETV-RL180M/S202G/M204V), whereas ETV failed to reduce HBVETV-RL180M/S202G/M204V DNA even at 1 µM. Once-daily peroral administration of CAdA reduced HBVETV-RL180M/S202G/M204V viremia (P = 0.0005) in human-liver-chimeric/ HBVETV-RL180M/S202G/M204V-infected mice, whereas ETV completely failed to reduce HBVETV-RL180M/S202G/M204V viremia. None of the mice had significant drug-related body-weight or serum human-albumin concentration changes. Molecular modeling suggests that a shallower HBV-RT hydrophobic pocket at the polymerase active site can better accommodate the slightly shorter 4'-cyano of CAdA-triphosphate (TP), but not the longer 4'-ethynyl of EFdA-TP. In contrast, the deeper HIV-1-RT pocket can efficiently accommodate the 4'-substitutions of both NRTIs. The ETV-TP's cyclopentyl ring can bind more efficiently at the shallow HBV-RT binding pocket. CONCLUSION: These data provide insights on the structural and functional associations of HBV- and HIV-1-RTs and show that CAdA may offer new therapeutic options for HBV patients.


Asunto(s)
Desoxiadenosinas/farmacología , Virus de la Hepatitis B/efectos de los fármacos , Animales , Farmacorresistencia Viral , Guanina/análogos & derivados , Guanina/farmacología , VIH-1/efectos de los fármacos , Ratones
11.
J Hepatol ; 63(3): 546-53, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25817219

RESUMEN

BACKGROUND & AIMS: Entecavir (ETV) is approved for the treatment of chronic hepatitis B virus (HBV) infections, but the virus can acquire resistance to the drug. This requires lamivudine resistance mutations (LAMr) and at least one additional mutation. Here, we characterized two novel mutations, rtI163V and rtA186T, associated with viral breakthrough (VBT) in an ETV-refractory patient. METHODS: HBV from an ETV-refractory patient was sequenced, and newly identified mutations were inserted into a replication-competent clone by mutagenesis. Clones were analyzed for replication efficacy and susceptibility to ETV in vitro. Chimeric mice with human hepatocytes were inoculated with the patient's serum at VBT, and monitored for viral mutation pattern using a next-generation sequencing approach. RESULTS: RtI163V and rtA186T mutations were detected together with LAMr (rtL180M and rtM204V) at VBT. RtA186T plus LAMr reduced susceptibility to ETV more than 111.1-fold compared with the wild-type clone, while rtI163V plus LAMr resulted in a 20.4-fold reduction. RtA186T significantly reduced viral replication efficacy, while the rtI163V mutation rescued it. Interestingly, the viral mutation pattern in the chimeric mice indicated dominant (or selective) proliferation of a clone containing rtI163V and rtA186T mutations plus LAMr under ETV treatment. Three-dimensional docking simulation indicated that rtA186T reduced the binding affinity of the HBV polymerase to ETV. CONCLUSIONS: VBT in this ETV-refractory patient is attributable to the novel ETV resistance mutations rtI163V and rtA186T. RtA186T was apparently responsible for ETV resistance but the selection of a clone with the double mutation plus LAMr suggests that rtI163V is required to sustain viral fitness.


Asunto(s)
Antivirales/uso terapéutico , Guanina/análogos & derivados , Hepatitis B Crónica/tratamiento farmacológico , Mutación , ADN Polimerasa Dirigida por ARN/genética , Adulto , Animales , Farmacorresistencia Viral , Guanina/uso terapéutico , Humanos , Ratones , Modelos Moleculares
12.
Gastroenterology ; 146(2): 562-72, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24184133

RESUMEN

BACKGROUND & AIMS: Cells of tumors associated with chronic inflammation frequently have altered patterns of DNA methylation, including hepatocellular carcinomas. Chronic hepatitis has also been associated with aberrant DNA methylation, but little is known about their relationship. METHODS: Pyrosequencing was used to determine the methylation status of cultured Huh7.5.1 hepatoma cells after hepatitis C virus (HCV) infection. We also studied mice with severe combined immunodeficiency carrying the urokinase-type plasminogen activator transgene controlled by an albumin promoter (urokinase-type plasminogen activator/severe combined immunodeficient mice), in which up to 85% of hepatocytes were replaced by human hepatocytes (chimeric mice). Mice were given intravenous injections of hepatitis B virus (HBV) or HCV, liver tissues were collected, and DNA methylation profiles were determined at different time points after infection. We also compared methylation patterns between paired samples of hepatocellular carcinomas and adjacent nontumor liver tissues from patients. RESULTS: No reproducible changes in DNA methylation were observed after infection of Huh7.5.1 cells with HCV. Livers from HBV- and HCV-infected mice had genome-wide, time-dependent changes in DNA methylation, compared with uninfected urokinase-type plasminogen activator/severe combined immunodeficient mice. There were changes in 160 ± 63 genes in HBV-infected and 237 ± 110 genes in HCV-infected mice. Methylation of 149 common genes increased in HBV- and HCV-infected mice; methylation of some of these genes also increased in hepatocellular carcinoma samples from patients compared with nontumor tissues. Expression of Ifng, which is expressed by natural killer cells, increased significantly in chimeric livers, in concordance with induction of DNA methylation, after infection with HBV or HCV. Induction of Ifng was reduced after administration of an inhibitor of natural killer cell function (anti-asialo GM1). CONCLUSIONS: In chimeric mice with humanized livers, infection with HBV and HCV appears to activate a natural kill cell-dependent innate immune response. This contributes to the induction and accumulation of aberrant DNA methylation in human hepatocytes.


Asunto(s)
Metilación de ADN , Hepatitis B/genética , Hepatitis C/genética , Hígado/virología , Adolescente , Adulto , Animales , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/inmunología , Carcinoma Hepatocelular/virología , Línea Celular Tumoral , Niño , Preescolar , Quimerismo , Islas de CpG , Epigénesis Genética , Femenino , Hepatitis B/complicaciones , Hepatitis B/inmunología , Hepatitis C/complicaciones , Hepatitis C/inmunología , Humanos , Inmunidad Innata , Células Asesinas Naturales/inmunología , Hígado/inmunología , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/inmunología , Neoplasias Hepáticas/virología , Activación de Linfocitos , Masculino , Ratones , Ratones SCID , Análisis de Secuencia por Matrices de Oligonucleótidos , Análisis de Secuencia de ADN , Adulto Joven
13.
Virol J ; 12: 153, 2015 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-26420301

RESUMEN

BACKGROUND: Major hydrophilic region in genomic HBV extending from aa99 to aa169, clustered with a highly conformational epitope, is critical to the antigenicity of hepatitis B surface antigen (HBsAg) and may affect the diagnosis of HBV in HBV screening test. So, this study aimed to characterize variants of S gene product of hepatitis B virus (HBV) isolated from patients with overt or occult HBV infection in north-eastern Egypt. METHODS: The study included sera of two different groups of volunteer blood donors (VBDs), 82 with overt HBV that were positive for HBsAg and anti-HBc and 343 donors negative for HBsAg eligible for donation. Of the latter group, only 44 were positive for anti-HBc. All anti-HBc positive sera were subjected to HBV DNA detection and partial sequence analysis targeting the HBV S gene. RESULTS: HBV DNA was detected in 22.7 % of HBsAg-/anti-HBc + (10/44 patients) and in 90 % of HBsAg + donors (74/82 patients) with significant statistical difference (P = 0.0001). Phylogenetic analysis showed that HBV strains retrieved from both groups were of genotype D. Amino acid escape mutation T125M was detected in only 2 samples of the occult infection group and in none of the overt group (P = 0.01). Different amino acid substitutions were identified in overt infection group: S143L/T (16.2 %, 12/74) and P120T/S (2.7 %, 2/74). Q129R was significantly more frequent in cases with occult HBV infection (40 %, 4/10) than overt group (6.8 %, 5/74) (P = 0.01). CONCLUSIONS: HBV genotype D predominated both in patients with overt and occult HBV infection. Different profiles of amino acid substitutions in the major hydrophilic region were seen in these two groups in Egypt.


Asunto(s)
Donantes de Sangre , Variación Genética , Antígenos de Superficie de la Hepatitis B/genética , Virus de la Hepatitis B/genética , Adulto , Sustitución de Aminoácidos , ADN Viral/química , ADN Viral/genética , Egipto , Femenino , Genotipo , Anticuerpos contra la Hepatitis B/sangre , Virus de la Hepatitis B/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Mutación Missense , Análisis de Secuencia de ADN , Adulto Joven
14.
Hepatol Res ; 45(13): 1363-7, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-25753008

RESUMEN

We report an adult T-cell leukemia-lymphoma (ATL) patient suffering from fatal reactivation of hepatitis B virus (HBV) infection after treatment with the anti-CC chemokine receptor 4 (CCR4) monoclonal antibody, mogamulizumab. HBV reactivation occurred without liver damage in this hepatitis B surface antigen (HBsAg) negative patient, who was seropositive for antibodies against the viral core and surface antigens at baseline, after two cycles of CHOP regimen (cyclophosphamide, doxorubicin, vincristine and prednisolone) followed by six cycles of THP-COP regimen (cyclophosphamide, pirarubicin, vincristine and prednisolone). Unexpectedly, mogamulizumab monotherapy for relapsed CCR4 positive ATL induced sudden and fatal liver failure due to HBV reactivation, despite antiviral prophylaxis with entecavir. This clinical course may not only offer important suggestions to prevent critical HBV reactivation in HBsAg positive cancer patients who receive immune-enhancing drugs such as anti-CCR4 antibody, but also provide a clue to understanding the pathogenesis of HBV reactivation following systemic chemotherapy.

15.
Hepatol Res ; 44(12): 1208-1216, 2014 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24372894

RESUMEN

AIM: Several studies have shown that high pretreatment concentrations of serum interferon-γ-inducible protein-10 (IP-10) are correlated with non-response to pegylated interferon (PEG-IFN) plus ribavirin (RBV) for chronic hepatitis C (CHC). However, there are few reports on their effect on the Asian population. METHODS: We enrolled 104 Japanese genotype 1 CHC individuals treated with PEG-IFN/RBV and 45 with PEG-IFN/RBV/telaprevir, and evaluated the impact of pretreatment serum IP-10 concentrations on their virological responses. RESULTS: The pretreatment serum IP-10 concentrations were not correlated with IL28B genotype. The receiver-operator curve analysis determined the cut-off value of IP-10 for predicting a sustained virological response (SVR) as 300 pg/mL. In multivariate analysis, the IL28B favorable genotype and IP-10 concentration of less than 300 pg/mL were independent factors for predicting SVR. In a subgroup of patients with the IL28B favorable genotype, the SVR rate was higher in the patients with IP-10 of less than 300 than in those with 300 pg/mL or more, whereas no patient with the IL28B unfavorable genotype and IP-10 of 300 pg/mL or more achieved SVR. Among the patients treated with PEG-IFN/RBV/telaprevir, low pretreatment concentrations of serum IP-10 were associated with a very rapid virological response, defined as undetectable HCV RNA at week 2 after the start of therapy. CONCLUSION: Pretreatment serum IP-10 concentrations are associated with treatment efficacy in PEG-IFN/RBV and with early viral kinetics of hepatitis C virus in PEG-IFN/RBV/telaprevir therapy.

16.
Gut ; 62(9): 1340-6, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23135762

RESUMEN

OBJECTIVE: Recent studies have demonstrated that genetic polymorphisms near the IL28B gene are associated with the clinical outcome of pegylated interferon α (peg-IFN-α) plus ribavirin therapy for patients with chronic hepatitis C virus (HCV). However, it is unclear whether genetic variations near the IL28B gene influence hepatic interferon (IFN)-stimulated gene (ISG) induction or cellular immune responses, lead to the viral reduction during IFN treatment. DESIGN: Changes in HCV-RNA levels before therapy, at day 1 and weeks 1, 2, 4, 8 and 12 after administering peg-IFN-α plus ribavirin were measured in 54 patients infected with HCV genotype 1. Furthermore, we prepared four lines of chimeric mice having four different lots of human hepatocytes containing various single nucleotide polymorphisms (SNP) around the IL28B gene. HCV infecting chimeric mice were subcutaneously administered with peg-IFN-α for 2 weeks. RESULTS: There were significant differences in the reduction of HCV-RNA levels after peg-IFN-α plus ribavirin therapy based on the IL28B SNP rs8099917 between TT (favourable) and TG/GG (unfavourable) genotypes in patients; the first-phase viral decline slope per day and second-phase slope per week in TT genotype were significantly higher than in TG/GG genotype. On peg-IFN-α administration to chimeric mice, however, no significant difference in the median reduction of HCV-RNA levels and the induction of antiviral ISG was observed between favourable and unfavourable human hepatocyte genotypes. CONCLUSIONS: As chimeric mice have the characteristic of immunodeficiency, the response to peg-IFN-α associated with the variation in IL28B alleles in chronic HCV patients would be composed of the intact immune system.


Asunto(s)
Hepacivirus/efectos de los fármacos , Hepatitis C Crónica , Interferón-alfa/farmacología , Interleucinas/genética , Polietilenglicoles/farmacología , ARN Viral/análisis , Ribavirina/farmacología , Animales , Antivirales/farmacología , Quimioterapia Combinada , Femenino , Hepatitis C Crónica/tratamiento farmacológico , Hepatitis C Crónica/genética , Humanos , Inmunidad Celular/efectos de los fármacos , Inmunidad Celular/genética , Interferones , Masculino , Ratones , Ratones SCID , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Proteínas Recombinantes/farmacología , Factores de Tiempo , Resultado del Tratamiento , Carga Viral/métodos
17.
J Clin Microbiol ; 51(11): 3484-91, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23946517

RESUMEN

We modified and automated a highly sensitive chemiluminescent enzyme immunoassay (CLEIA) for surface antigen (HBsAg) detection using a combination of monoclonal antibodies, each for a specific epitope of HBsAg, and by improving an earlier conjugation technique. Of 471 hepatitis B virus (HBV) carriers seen in our hospital between 2009 and 2012, 26 were HBsAg seronegative as determined by the Abbott Architect assay. The Lumipulse HBsAg-HQ assay was used to recheck those 26 patients who demonstrated seroclearance by the Abbott Architect assay. The performance of the Lumipulse HBsAg-HQ assay was compared with that of a quantitative HBsAg detection system (Abbott Architect) and the Roche Cobas TaqMan HBV DNA assay (CTM) (lower limit of detection, 2.1 log copies/ml) using blood serum samples from patients who were determined to be HBsAg seronegative by the Abbott Architect assay. Ten patients had spontaneous HBsAg loss. Of 8 patients treated with nucleotide analogues (NAs), two were HBsAg seronegative after stopping lamivudine therapy and 6 were HBsAg seronegative during entecavir therapy. Eight acute hepatitis B (AH) patients became HBsAg seronegative. Of the 26 patients, 16 were HBsAg positive by the Lumipulse HBsAg-HQ assay but negative by the Abbott Architect assay. The differences between the two assays in terms of detectable HBsAg persisted over the long term in the spontaneous loss group (median, 10 months), the NA-treated group (2.5 months), and the AH group (0.5 months). In 9 patients, the Lumipulse HBsAg-HQ assay detected HBsAg when HBV DNA was negative by the CTM assay. HBsAg was also detected by the Lumipulse HBsAg-HQ assay in 4 patients with an anti-HBs concentration of >10 mIU/ml, 3 of whom had no HBsAg escape mutations. The automatic, highly sensitive HBsAg CLEIA Lumipulse HBsAg-HQ is a convenient and precise assay for HBV monitoring.


Asunto(s)
Técnicas de Laboratorio Clínico/métodos , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis B/diagnóstico , Adulto , Anciano , Antivirales/uso terapéutico , Automatización de Laboratorios/métodos , Femenino , Hepatitis B/tratamiento farmacológico , Humanos , Técnicas para Inmunoenzimas/métodos , Mediciones Luminiscentes , Masculino , Persona de Mediana Edad , Sensibilidad y Especificidad , Suero/química
18.
J Med Virol ; 84(4): 587-95, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22337297

RESUMEN

The transmission rate of intra-familial hepatitis B virus (HBV) and mode of transmission were investigated in north eastern Egypt. HBV infection was investigated serologically and confirmed by molecular evolutionary analysis in family members (N = 230) of 55 chronic hepatitis B carriers (index cases). Hepatitis B surface antigen (HBsAg) and hepatitis B core antibody (anti-HBc) prevalence was 12.2% and 23% among family members, respectively. HBsAg carriers were prevalent in the age groups; <10 (16.2%) and 21-30 years (23.3%). The prevalence of HBsAg was significantly higher in the family members of females (19.2%) than males (8.6%) index cases (P = 0.031). HBsAg and anti-HBc seropositive rates were higher significantly in the offspring of females (23%, 29.8%) than those of the males index cases (4.3%, 9.8%) (P = 0.001, 0.003), as well as higher in the offspring of an infected mother (26.5, 31.8%) than those of an infected father (4.7%, 10.5%) (P = 0.0006, 0.009). No significant difference was found in HBsAg seropositive rates between vaccinated (10.6%) and unvaccinated family members (14.8%). Phylogenetic analysis of the preS2 and S regions of HBV genome showed that the HBV isolates were of subgenotype D1 in nine index cases and 14 family members. HBV familial transmission was confirmed in five of six families with three transmission patterns; maternal, paternal, and sexual. It is concluded that multiple intra-familial transmission routes of HBV genotype D were determined; including maternal, paternal and horizontal. Universal HBV vaccination should be modified by including the first dose at birth with (HBIG) administration to the newborn of mothers infected with HBV.


Asunto(s)
Salud de la Familia , Virus de la Hepatitis B/clasificación , Virus de la Hepatitis B/genética , Hepatitis B/transmisión , Hepatitis B/virología , Adolescente , Adulto , Niño , Preescolar , Análisis por Conglomerados , ADN Viral/química , ADN Viral/genética , Egipto/epidemiología , Femenino , Genotipo , Hepatitis B/epidemiología , Anticuerpos contra la Hepatitis B/sangre , Antígenos del Núcleo de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/sangre , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Análisis de Secuencia de ADN , Estudios Seroepidemiológicos , Adulto Joven
19.
Viruses ; 14(11)2022 11 08.
Artículo en Inglés | MEDLINE | ID: mdl-36366568

RESUMEN

Hepatitis B virus (HBV) specifically infects human hepatocytes and increases the risks of cirrhosis and liver cancer. Currently, nucleic acid analogs are the main therapeutics for chronic hepatitis caused by HBV infection. Although nucleic acid analogs can eliminate HBV DNA by inhibiting HBV reverse transcriptase, they cannot lead to negative conversion of covalently closed circular DNA (cccDNA) and hepatitis B surface antigen (HBsAg). In this study, we revealed that the antifilarial drug ivermectin suppresses HBV production by a different mechanism from the nucleic acid analog entecavir or Na+ taurocholate co-transporting polypeptide-mediated entry inhibitor cyclosporin A. Ivermectin reduced the levels of several HBV markers, including HBsAg, in HBV-infected human hepatocellular carcinoma cells (HepG2-hNTCP-C4 cells) and humanized mouse hepatocytes (PXB hepatocytes). In addition, ivermectin significantly decreased the expression of HBV core protein and the nuclear transporter karyopherin α2 (KPNA2) in the nuclei of HepG2-hNTCP-C4 cells. Furthermore, depletion of KPNA1-6 suppressed the production of cccDNA. These results suggest that KPNA1-6 is involved in the nuclear import of HBV and that ivermectin suppresses the nuclear import of HBV by inhibiting KPNA2. This study demonstrates the potential of ivermectin as a novel treatment for hepatitis B.


Asunto(s)
Hepatitis B Crónica , Hepatitis B , Ratones , Animales , Humanos , Virus de la Hepatitis B/genética , Antígenos de Superficie de la Hepatitis B/metabolismo , Ivermectina/farmacología , ADN Circular/metabolismo , ADN Viral/metabolismo , Replicación Viral/genética , alfa Carioferinas/metabolismo
20.
Am J Respir Cell Mol Biol ; 45(4): 795-803, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21357438

RESUMEN

Asbestos causes malignant tumors such as lung cancer and malignant mesothelioma (MM). To determine whether asbestos exposure causes reduction of antitumor immunity, we established an in vitro T-cell line model of low-dose and continuous exposure to asbestos using an human adult T-cell leukemia virus-1 immortalized human polyclonal T-cell line, MT-2, and revealed that MT-2 cells exposed continuously to asbestos showed resistance to asbestos-induced apoptosis. In addition, the cells presented reduction of surface CXCR3 chemokine receptor expression and IFN-γ production. In this study, to confirm that these findings are suitable for clinical translation, surface CXCR3 and IFN-γ expression were analyzed using freshly isolated human CD4(+) T cells derived from healthy donors and patients with pleural plaque (PP) or MM. The results revealed that CXCR3 and IFN-γ expression in the ex vivo model were reduced in some cases. Additionally, CXCR3 expression in CD4(+) T cells from PPs and MMs was significantly reduced compared with that from healthy donors, and CD4(+) T cells from patients with MMs exhibited a marked reduction in IFN-γ mRNA levels after stimulation in vitro. Moreover, CD4(+)CXCR3(+) T cells in lymphocytes from MMs showed a tendency for an inverse correlation with its ligand CXCL10/IP10 in plasma. These findings show reduction of antitumor immune function in asbestos-exposed patients and indicate that CXCR3, IFN-γ, and CXCL10/IP10 may be candidates to detect and monitor disease status.


Asunto(s)
Asbestos Serpentinas/toxicidad , Asbestosis/etiología , Linfocitos T CD4-Positivos/efectos de los fármacos , Materiales de Construcción/toxicidad , Neoplasias Pulmonares/inducido químicamente , Mesotelioma/inducido químicamente , Receptores CXCR3/metabolismo , Escape del Tumor/efectos de los fármacos , Adulto , Apoptosis/efectos de los fármacos , Asbestosis/genética , Asbestosis/inmunología , Asbestosis/patología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/patología , Estudios de Casos y Controles , Línea Celular Tumoral , Quimiocina CXCL10/sangre , Relación Dosis-Respuesta a Droga , Regulación hacia Abajo , Femenino , Humanos , Interferón gamma/genética , Interferón gamma/metabolismo , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/inmunología , Neoplasias Pulmonares/patología , Masculino , Mesotelioma/genética , Mesotelioma/inmunología , Mesotelioma/patología , Persona de Mediana Edad , ARN Mensajero/metabolismo , Factores de Tiempo
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