Hepatitis B Virus Suppression Research Articles

Natural killer cell activation contributes to hepatitis B viral control in a mouse model

The roles of CD4 + T cells and CD8 + T cells in hepatitis B virus (HBV) infection have been well documented. However, the role of innate immunity in HBV infection remains obscure. Here we examined the effect of activation of innate immunity by polyinosinic: polycytidylic acid (PolyI:C) on HBV infection. A chronic HBV replication mouse model was established by hydrodynamical injection of pAAV/HBV1.2 plasmid into C57BL/6 mice. We found that HBV did not seem to induce an active NK-cell response in the mouse model. Early PolyI:C treatment markedly decreased serum HBV levels and led to HBV clearance. Following PolyI:C injection, NK cells were activated and accumulated in the liver. Depletion of NK cells markedly attenuated the anti-HBV activity of PolyI:C. Moreover, we found that IFN-γ production from NK cells was essential for the antiviral effect of PolyI:C in the model. Importantly, activation of NK cells by PolyI:C could also lead to HBV suppression in HBV-tolerant mice and HBV-transgenic mice. These results suggest that activated NK cells might suppress HBV and contribute to HBV clearance during natural HBV infection. In addition, therapeutic activation of NK cells may represent a new strategy for the treatment of chronic HBV infection.

Transforming growth factor \u03b2-activated kinase 1 transcriptionally suppresses hepatitis B virus replication

Hepatitis B Virus (HBV) replication in hepatocytes is restricted by the host innate immune system and related intracellular signaling pathways. Transforming growth factor β-activated kinase 1 (TAK1) is a key mediator of toll-like receptors and pro-inflammatory cytokine signaling pathways. Here, we report that silencing or inhibition of endogenous TAK1 in hepatoma cell lines leads to an upregulation of HBV replication, transcription, and antigen expression. In contrast, overexpression of TAK1 significantly suppresses HBV replication, while an enzymatically inactive form of TAK1 exerts no effect. By screening TAK1-associated signaling pathways with inhibitors and siRNAs, we found that the MAPK-JNK pathway was involved in TAK1-mediated HBV suppression. Moreover, TAK1 knockdown or JNK pathway inhibition induced the expression of farnesoid X receptor α, a transcription factor that upregulates HBV transcription. Finally, ectopic expression of TAK1 in a HBV hydrodynamic injection mouse model resulted in lower levels of HBV DNA and antigens in both liver and serum. In conclusion, our data suggest that TAK1 inhibits HBV primarily at viral transcription level through activation of MAPK-JNK pathway, thus TAK1 represents an intrinsic host restriction factor for HBV replication in hepatocytes.

An improved understanding of severe liver morbidity in HIV-infected individuals

An improved understanding of severe liver morbidity in HIV-infected individuals

Clinical Relapse After Cessation of Tenofovir Therapy inHepatitis B e Antigen-Negative Patients.

Of the hepatitis B e antigen-negative chronic hepatitis B patients with more than 1 year of sustained hepatitis B virus (HBV) suppression during therapy, the 1-year clinical relapse rate after cessation of entecavir therapy was 45%, of which 25.6% occurred within 6 months. The events after cessation of another preferred drug tenofovir were investigated. A retrospective-prospective study was conducted in 85 hepatitis B e antigen-negative chronic hepatitis B patients with sustained HBV suppression who had stopped tenofovir therapy and were monitored every 1 to 3 months for a median duration of 39 weeks (range, 4-133 wk). Clinical relapse occurred in 38 patients, 57.9% and 86.8% within 3 and 6 months, respectively, with an estimated 1-year cumulative incidence of 52%. The optimal duration of therapy and consolidation therapy were calculated to be 3 and 2 years, respectively. Of the relapsers, 81.6% and 57.9% showed an alanine aminotransferase level greater than 5 and 10 times the upper limit of normal, respectively, 23.7% showed a bilirubin level of 2 mg/dL or greater, and 2 developed hepatic decompensation. Relapsers had significantly higher pretherapy baseline hepatitis B surface antigen level, more prior anti-HBV therapy experience, later alanine aminotransferase level normalization, and a shorter duration of treatment and consolidation therapy. Cox regression analyses showed that treatment for more than 3 years combined with consolidation therapy for more than 2 years was an independent significant manageable factor of clinical relapse (adjusted hazard ratio, 0.387; P= .008). With this combination, the clinical relapse rate was reduced to 30%. Clinical relapses occurred mostly within 6 months, with high alanine aminotransferase and serum bilirubin levels. Closer monitoring, monthly in the first 3 to 6 months, with timely re-treatment is mandatory for a safe cessation of tenofovir therapy.

Risk Factors for Hepatocellular Carcinoma in Cirrhotic Patients with Chronic Hepatitis B.

To investigate the clinical and genetic risk factors associated with hepatocellular carcinoma (HCC) in cirrhotic patients with chronic hepatitis B (CHB). Nine hundred forty-nine Chinese Han patients with CHB were studied, including noncirrhotic patients without HCC (N = 234), cirrhotic patients without (N = 281) and with HCC (N = 434). Patients were genotyped for 10 candidate single nucleotide polymorphisms (SNPs) by the polymerase chain reaction (PCR)-ligase detection reaction (LDR) method. By multivariate logistic regression analysis adjusted for Child-Pugh scores, noneffective antiviral treatment, drinking history, family history of HCC, and age ≥50 years old were associated with HCC risk (odds ratio [OR] = 5.923, 2.456, 2.241, 1.955, respectively). Sixty-two of 170 cirrhotic patients who achieved sustained virological suppression by antiviral treatment developed HCC, with fatty liver disease, family history of HCC, and family history of hepatitis B virus (HBV) infection as the risk factors (OR = 11.646, 3.339, 2.537, respectively). The SNPs associated with HCC risk in patients with cirrhosis and CHB were rs11536889 in TLR4 and rs2853744 in SPP1. Polymorphisms of TLR4 rs2149356, AP3S2 rs2290351, STXBP5L rs2169302, MLEC rs7976497, and SOCS3 rs4969168 were associated with HCC risk in specific stratified analyses with gender, age, and drinking history in the cirrhotic patients. Inadequate antiviral treatment, family history of HCC, drinking history, and age ≥50 years old are risk factors for HCC. Sustained suppression of HBV does not eliminate the risk of HCC. Specific host genetic factors may impact HCC development in Han Chinese cirrhotic patients with CHB, including SNPs in TLR4, SPP1, AP3S2, STXBP5L, MLEC, and SOCS3, which warrant further validation in additional cohorts.

Effects of long-term tenofovir-based combination antiretroviral therapy in HIV-hepatitis B virus coinfection on persistent hepatitis B virus viremia and the role of hepatitis B virus quasispecies diversity.

Hepatitis B virus (HBV) can persist in some HIV-HBV coinfected individuals on tenofovir disoproxil fumarate (TDF)-containing combination antiretroviral therapy (cART) but HBV resistance to TDF has not been reported and the source of persistent HBV DNA on TDF is poorly understood. The aims of this study were to assess long-term HBV suppression in HIV-HBV coinfected individuals receiving TDF and investigate quasispecies variation using ultradeep pyrosequencing (UDPS). Ninety-two HIV-HBV coinfected participants on, or about to commence, TDF-containing cART were enrolled [Australia (n = 40), Thailand (n = 52)] and followed for 2 years with study visits every 6 months. HBV reverse transcriptase sequencing was performed on samples with HBV DNA more than 400 IU/ml by population-based methods and UDPS. Quasispecies diversity was assessed using Shannon entropy. Over 24 months, viremia was detected at least once in 17% (n = 16) of the cohort. Novel mutations were not identified in on TDF samples tested by population-based sequencing (n = 19). Using UDPS, the median Shannon entropy value in samples prior to TDF in patients aviremic on TDF was not statistically different from those who were viremic on TDF (n = 50; 8.4 and 9.1, respectively, P = 0.9). Longitudinal Shannon entropy analysis of on TDF samples from five participants showed three individuals with significant changes in viral diversity over time. Persistent viremia on TDF-containing cART is common but TDF-resistance was not detected. In some individuals, changes in viral diversity over time were observed on TDF which could potentially be active viral replication. Further follow-up will be needed to determine the clinical significance of detectable HBV DNA on TDF-containing cART.

Anti-viral role of toll like receptor 4 in hepatitis B virus infection: An in vitro study.

AIMToll like receptors plays a significant anti-viral role in different infections. The aim of this study was to look into the role of toll like receptor 4 (TLR4) in hepatitis B virus (HBV) infection.METHODSReal time PCR was used to analyze the transcription of TLR4 signaling molecules, cell cycle regulators and HBV DNA viral load after triggering the HepG2.2.15 cells with TLR4 specific ligand. Nuclear factor (NF)-κB translocation on TLR4 activation was analyzed using microscopic techniques. Protein and cell cycle analysis was done using Western Blot and FACS respectively.RESULTSThe present study shows that TLR4 activation represses HBV infection. As a result of HBV suppression, there are several changes in host factors which include partial release in G1/S cell cycle arrest and changes in host epigenetic marks. Finally, it was observed that anti-viral action of TLR4 takes place through the NF-κB pathway.CONCLUSIONThe study shows that TLR4 activation in HBV infection brings about changes in hepatocyte microenvironment and can be used for developing a promising therapeutic target in future.

Indoleamine-2,3-dioxygenase as an effector and an indicator of protective immune responses in patients with acute hepatitis B.

Indoleamine-2, 3-dioxygenase (IDO), an interferon-γ-inducible enzyme catalyzing tryptophan into kynurenine, exerts dual functions in infectious diseases, acting as a suppressor of intracellular pathogens and as an immune regulator. We explored the roles of IDO in hepatitis B virus (HBV) clearance from infected patients. We examined IDO activity, serum chemokines, and cytokines in 53 HBV-positive patients (25 acute hepatitis, 14 chronic hepatitis, and 14 hepatic flare) and 14 healthy volunteers. In order to clarify the mechanisms of IDO induction and its impact on HBV replication, we used a culture model consisting of human natural killer cells, plasmacytoid dendritic cells, and HBV-transfected Huh7 cells in which IDO expression is controlled. A robust activation of IDO with an inverse correlation of alanine aminotransferase at the peak was observed in patients with acute hepatitis B but not in patients with hepatic flare. In acute hepatitis patients who eventually cleared HBV, IDO activity, chemokine (C-X-C motif) ligand 9 (CXCL9), CXCL10, and CXCL11 increased at the peak of alanine aminotransferase. In contrast, in patients with hepatic flare, IDO activity remained at lower levels during the observation period, regardless of the surge of CXCL9, CXCL10, and CXCL11 at the alanine aminotransferase peak. Natural killer cells and plasmacytoid dendritic cells synergistically produced interferon-γ and interferon-α, thereby enhancing IDO activity and HBV suppression in Huh7 cells. Such suppressor capacity of IDO on HBV was abrogated in IDO-knockout cells and recovered by the reinduction of IDO in the cells. IDO is an anti-HBV effector and an indicator of subsequent immune responses operative during the early phase of infection; its activity is boosted by coexisting natural killer cells and plasmacytoid dendritic cells.

Antiviral therapy in chronic hepatitis B viral infection during pregnancy: A systematic review and meta-analysis.

Perinatal or mother-to-child transmission (MTCT) of hepatitis B virus (HBV) remains the major risk factor for chronic HBV infection worldwide. In addition to hepatitis B immune globulin and vaccination, oral antiviral therapies in highly viremic mothers can further decrease MTCT of HBV. We conducted a systematic review and meta-analysis to synthesize the evidence on the efficacy and maternal and fetal safety of antiviral therapy during pregnancy. A protocol was developed by the American Association for the Study of Liver Diseases guideline writing committee. We searched multiple databases for controlled studies that enrolled pregnant women with chronic HBV infection treated with antiviral therapy. Outcomes of interest were reduction of MTCT and adverse outcomes to mothers and newborns. Study selection and data extraction were done by pairs of independent reviewers. We included 26 studies that enrolled 3622 pregnant women. Antiviral therapy reduced MTCT, as defined by infant hepatitis B surface antigen seropositivity (risk ratio = 0.3, 95% confidence interval 0.2-0.4) or infant HBV DNA seropositivity (risk ratio = 0.3, 95% confidence interval 0.2-0.5) at 6-12 months. No significant differences were found in the congenital malformation rate, prematurity rate, and Apgar scores. Compared to control, lamivudine or telbivudine improved maternal HBV DNA suppression at delivery and during 4-8 weeks' postpartum follow-up. Tenofovir showed improvement in HBV DNA suppression at delivery. No significant differences were found in postpartum hemorrhage, cesarean section, and elevated creatinine kinase rates. Antiviral therapy improves HBV suppression and reduces MTCT in women with chronic HBV infection with high viral load compared to the use of hepatitis B immunoglobulin and vaccination alone; the use of telbivudine, lamivudine, and tenofovir appears to be safe in pregnancy with no increased adverse maternal or fetal outcome.

Cleaved c-FLIP mediates the antiviral effect of TNF-α against hepatitis B virus by dysregulating hepatocyte nuclear factors

Cytokines are key molecules implicated in the defense against virus infection. Tumor necrosis factor-alpha (TNF-α) is well known to block the replication of hepatitis B virus (HBV). However, the molecular mechanism and the downstream effector molecules remain largely unknown. In this study, we investigated the antiviral effect and mechanism of p22-FLIP (FLICE-inhibitory protein) by ectopic expression in vitro and in vivo. In addition, to provide the biological relevance of our study, we examined that the p22-FLIP is involved in TNF-α-mediated suppression of HBV in primary human hepatocytes. We found that p22-FLIP, a newly discovered c-FLIP cleavage product, inhibited HBV replication at the transcriptional level in both hepatoma cells and primary human hepatocytes, and that c-FLIP conversion to p22-FLIP was stimulated by the TNF-α/NF-κB pathway. p22-FLIP inhibited HBV replication through the upregulation of HNF3β but downregulation of HNF4α, thus inhibiting both HBV enhancer elements. Finally, p22-FLIP potently inhibited HBV DNA replication in a mouse model of HBV replication. Taken together, these findings suggest that the anti-apoptotic p22-FLIP serves a novel function of inhibiting HBV transcription, and mediates the antiviral effect of TNF-α against HBV replication.

The long-term benefits of nucleos(t)ide analogs in compensated HBV cirrhotic patients with no or small esophageal varices: A 12-year prospective cohort study

Esophageal varices (EV) are a marker of disease severity in compensated cirrhosis due to hepatitis B virus (HBV) which predicts also the risk of hepatocellular carcinoma (HCC), clinical decompensation and anticipated liver related death. The dynamics and prognostic significance of EV in patients under long-term HBV suppression by nucleos(t)ide analogs (NUC), are poorly known. A standardized protocol (Baveno) including 414 upper gastrointestinal (GI) endoscopies was applied to 107 HBeAg-negative compensated cirrhotic patients (93% Child-Pugh A) during a median of 12 (range 2 to 17) years of NUC therapy. Patients who initially started on lamivudine (LMV) and then developed resistance (LMV-R), were rescued by early administration of adefovir, or were switched to tenofovir. Surveillance included serum HBV DNA every three months and abdominal ultrasound every six months. Twenty-seven patients had baseline F1 EV which regressed in 18, remained unchanged in eight and progressed in one patient; the 12-year cumulative incidence of EV regression was 83% (95% CI: 52-92%). De novo F1/F2 EV developed in 6/80 patients with a 12-year cumulative incidence of 10% (95% CI: 5-20%). Six of seven patients with de novo varices or progression of pre-existing varices had either a clinical breakthrough due to LMV-R and/or developed a HCC. No bleedings from ruptured EV occurred, 12 patients died (9 HCC) and 15 were transplanted (13 HCC): the 12-year cumulative incidence of HCC and overall survival was 33% (95% CI: 24-42%) and 76% (95% CI: 67-83%), respectively. Long-term pharmacological suppression of HBV in HBeAg-seronegative patients with compensated cirrhosis leads to a significant regression of pre-existing EV accompanied by a negligible risk of developing de novo EV.

Liver Fibrosis by Transient Elastography and Virologic Outcomes After Introduction of Tenofovir in Lamivudine-Experienced Adults With HIV and Hepatitis B Virus Coinfection in Ghana.

Antiretroviral treatment (ART) programs in sub-Saharan Africa have for many years included lamivudine as the sole hepatitis B virus (HBV) inhibitor. Long-term outcomes and the effects of introducing tenofovir as part of ART in these populations have not been characterized. The study comprised a cross-sectional analysis of 106 human immunodeficiency virus (HIV)/HBV-coinfected subjects maintained on lamivudine, as well as a prospective analysis of 76 lamivudine-experienced subjects who introduced tenofovir. Patients underwent assessment of liver fibrosis by transient elastography (TE) and testing to characterize HIV type 1 (HIV-1) and HBV replication. After a median of 45 months of lamivudine treatment, HIV-1 RNA and HBV DNA were detectable in 35 of 106 (33.0%) and 54 of 106 (50.9%) subjects, respectively, with corresponding drug resistance rates of 17 of 106 (16.0%) and 31 of 106 (29.2%), respectively. Median TE values were 5.7 kPa (interquartile range, 4.7-7.2 kPa) and independently associated with HBV DNA load, aspartate aminotransferase levels, and platelet counts; 13 of 106 (12.3%) subjects had TE measurements >9.4 kPa. Twelve months after the first assessment, and a median of 7.8 months after introducing tenofovir, HBV DNA levels declined by a mean of 1.5 log10 IU/mL (P < .001). TE values changed by a mean of -0.2 kPa (P = .097), and declined significantly in subjects who had pretenofovir HBV DNA levels >2000 IU/mL (mean, -0.8 kPa; P = .048) or TE values >7.6 kPa (mean, -1.2 kPa; P = .021). HIV-1 RNA detection rates remained unchanged. A proportion of HIV/HBV-coinfected patients on long-term lamivudine-containing ART had poor HIV and HBV suppression, drug resistance, and TE values indicative of advanced liver fibrosis. Tenofovir improved HBV control and reduced liver stiffness in subjects with high HBV DNA load and TE values.

Outcomes in HIV/HBV-Coinfected Patients in the Tenofovir Era Are Greatly Affected by Immune Suppression.

HIV-infected patients have higher mortality when coinfected with hepatitis B virus (HBV). With potent highly active antiretroviral therapy (HAART) and the use of tenofovir (TDF), outcomes may improve. Our objective was to determine the clinical and virological outcomes of a HIV/HBV-Coinfected cohort at our center since TDF became available. We retrospectively studied all HIV/HBV-Coinfected adults followed between 2002 and 2012 for ≥3 months. Outcome measurements included HBV DNA suppression, HBV e-antigen (HBeAg) and HBV surface antigen (HBsAg) clearance, cirrhosis diagnosis, development of liver complications, and overall and liver-related mortality. Predicting factors were assessed with log-rank test and logistic regression. Median time to follow-up of the 99 patients included was 5 years. Undetectable HBV DNA and HBsAg loss were achieved by 65% and 18%, respectively. Overall and liver-related mortality rates were 4.58 and 0.91 per 100 person-years, respectively. Most patients died of causes unrelated to the liver. Four patients died from hepatocellular carcinoma (HCC) and one, hepatitis C virus (HCV) coinfected, from liver failure. Higher CD4 counts at last follow-up were associated with HBV suppression (odds ratio [OR] 1.004, 95% confidence interval [CI] 1.001-1.006, P=.007), HBeAg loss (OR 1.003, 95% CI 1-1.005, P=.02), HBsAg loss (CD4 count>700 cells/mm3, OR 3.80, 95% CI 1.06-13.58, P=.04), and survival (OR .994, 95% CI 0.990-0.997, P<.0001). HCV coinfection was associated with higher overall mortality (OR 7.74, 95% CI 1.47-40.81, P=.02). Mortality was high and most often unrelated to liver disease in this HIV/HBV-Coinfected cohort treated predominantly with TDF-containing HAART. Optimal CD4 counts predicted survival and the achievement of HBV virological end points. Tenofovir prevented liver decompensation but not HCC, which was the predominant cause of liver death.

Extended survival of patients with persistently suppressed hepatitis B transplanted for hepatocellular carcinoma.

Hepatocellular carcinoma (HCC) has become a major cause of liver-related death and indication to liver transplantation (LT) in patients with chronic hepatitis B virus (HBV) infection following the widespread adoption of antiviral therapy with nucleos(t)ide analogs (NUCs). Yet, the long-term outcome of patients undergoing liver transplantation for an HCC developed during effective NUC treatment is unknown. We evaluated 101 patients with persistently compensated cirrhosis who were consecutively transplanted for HCC in two centers in Milan. At LT, 91 (90%) patients had undetectable serum HBV DNA (<12 IU/ml) and 90 (89%) were within Milan criteria (MC). All patients received post-transplant HBV prophylaxis with specific immunoglobulins (HBIgs) and NUCs. End-points were long-term patient survival and recurrence of HCC and HBV. During 106 (range 3-165) months following LT, HCC recurred in 11 (11%) patients (nine beyond MC at explant, two with HBV recurrence). Age (HR 1.1, 95%CI 1.0-1.2, P = 0.04) and exceeding MC (HR 9.6, 95%CI 2.9-32, P < 0.0001) were the only independent pretransplant predictors of tumour recurrence. The 10-year cumulative rate of HCC recurrence was 7% among patients transplanted within MC compared with 45% among those beyond MC at LT (P = 0.004). Overall, 18 patients (18%, nine HCC, nine non liver-related events) died with a 10-year cumulative probability of overall and liver-related survival of 79% and 89% respectively. Extended survival of HBV cirrhotics transplanted for HCC can be achieved by coupling MC at listing with persistent pharmacological suppression of HBV.

Dual gRNAs guided CRISPR/Cas9 system inhibits hepatitis B virus replication.

To screen and investigate the effective gRNAs against hepatitis B virus (HBV) of genotypes A-D. A total of 15 gRNAs against HBV of genotypes A-D were designed. Eleven combinations of two above gRNAs (dual-gRNAs) covering the regulatory region of HBV were chosen. The efficiency of each gRNA and 11 dual-gRNAs on the suppression of HBV (genotypes A-D) replication was examined by the measurement of HBV surface antigen (HBsAg) or e antigen (HBeAg) in the culture supernatant. The destruction of HBV-expressing vector was examined in HuH7 cells co-transfected with dual-gRNAs and HBV-expressing vector using polymerase chain reaction (PCR) and sequencing method, and the destruction of cccDNA was examined in HepAD38 cells using KCl precipitation, plasmid-safe ATP-dependent DNase (PSAD) digestion, rolling circle amplification and quantitative PCR combined method. The cytotoxicity of these gRNAs was assessed by a mitochondrial tetrazolium assay. All of gRNAs could significantly reduce HBsAg or HBeAg production in the culture supernatant, which was dependent on the region in which gRNA against. All of dual gRNAs could efficiently suppress HBsAg and/or HBeAg production for HBV of genotypes A-D, and the efficacy of dual gRNAs in suppressing HBsAg and/or HBeAg production was significantly increased when compared to the single gRNA used alone. Furthermore, by PCR direct sequencing we confirmed that these dual gRNAs could specifically destroy HBV expressing template by removing the fragment between the cleavage sites of the two used gRNAs. Most importantly, gRNA-5 and gRNA-12 combination not only could efficiently suppressing HBsAg and/or HBeAg production, but also destroy the cccDNA reservoirs in HepAD38 cells. These results suggested that CRISPR/Cas9 system could efficiently destroy HBV expressing templates (genotypes A-D) without apparent cytotoxicity. It may be a potential approach for eradication of persistent HBV cccDNA in chronic HBV infection patients.

Detectability and clinical significance of serum hepatitis B virus ribonucleic acid.

Serum hepatitis B virus (HBV) RNA is detected during treatment with nucleoside analogue as a consequence of interrupted reverse transcription (RT) and unaffected replicative intermediates. The presence of serum HBV RNA in chronic HBV patients is confirmed by using ribonuclease digestion. Serum HBV RNA is differentially inhibited by interferon, but not by nucleoside analogue. The inhibitory effect of interferon on HBV RNA replicative intermediates may potentiate the suppression of HBV replication. Clinical significance of serum HBV RNA includes: (I) reflect the antiviral potency of nucleoside analogue; (II) predictor of early emergence of viral mutation during lamivudine therapy; (III) independently predict initial virologic response or earlier HBV suppression during nucleoside analogue therapy; (IV) predict HBV reactivation after discontinuation of nucleoside analogue. Thus, serum HBV RNA might be useful to optimize treatment efficacy in patients with chronic HBV, including shifting of oral antivirals or conversion to immunomodulatory agent i.e., interferon. Furthermore, serum HBV RNA levels correlate better with serum quantitative HBsAg (qHBsAg) than with serum HBV DNA levels. The predictive role of serum HBV RNA in long-term treatment effects of nucleoside analogue needs further study.

Restitution of gene expression and histone acetylation signatures altered by hepatitis B virus through antiviral microRNA-like molecules in nontransformed murine hepatocytes.

BackgroundVirus-host interactions result in altered gene expression profiles in host cell nuclei and enable virus particle production, thus obligatorily involving changes in their epigenomes. Neither such epigenome changes nor their response to antiviral treatment have been extensively studied to date, although viral infections are known to contribute to the long-term development of severe secondary diseases, for example, hepatocellular carcinoma. This may be causally linked to virus-induced persistent plastic chromatin deformations.ResultsWe studied whether impaired hepatitis B virus (HBV) replication can lead to the restitution of epigenome signatures hypothesizing that hepatocytes alternatively could adopt a ‘memory’ state of the infection; that is, the chromatin could persist in a HBV-induced configuration potentially inheritable between dividing hepatocytes. We therefore determined epigenomic signatures and gene expression changes altered by HBV and the effects of suppressed HBV replication in nontransformed hepatocytes of newborn mice. Further we investigated differential histone acetyltransferase and histone deacetylase activities in HBV-negative and HBVpositive hepatocytes, as well as the effects of HBV suppression on gene expression and the chromatin landscape. We show that the expression of several genes and the chromatin landscape become altered upon HBV infection, including global hypoacetylation of H2A.Z and H3K9. Reporter assays monitoring the activities of histone acetyltransferases or histone deacetylases, respectively, suggest that hypoacetylation most probably depends on elevated sirtuin deacetylase activity, but not on class I/II histone deacetylases. Using Micrococcus nuclease to study the chromatin accessibility in met murine-D3 and hepatitis B virus met murine hepatocytes, we demonstrate that the observed differences in H2A.Z/H3K9 acetylation lead to global chromatin structure changes. At all selected sites examined by chromatin immunoprecipitation and quantitative real-time PCR, these effects can be partly restituted via the nucleoside analog reverse transcriptase inhibitor 3TC or using anti-HBV microRNA-like molecules.ConclusionsIncreased sirtuin activity might lead to global histone hypoacetylation signatures, which could contribute to the HBV-induced pathomechanism in nontransformed hepatocytes. Using several techniques to suppress HBV replication, we observed restituted gene expression and chromatin signature patterns reminiscent of noninfected hepatocytes. Importantly, ectopic expression of antiviral short-hairpin RNA, but not microRNA-like molecules, provoked intolerable off-target effects on the gene expression level.Electronic supplementary materialThe online version of this article (doi:10.1186/1868-7083-6-26) contains supplementary material, which is available to authorized users.

Factors Associated With Delayed Hepatitis B Viral Suppression on Tenofovir Among Patients Coinfected With HBV-HIV in the CNICS Cohort

Despite widespread use in HIV and hepatitis B virus (HBV) infection, the effectiveness of tenofovir (TDF) has not been studied extensively outside of small cohorts of coinfected patients with HBV-HIV. We examined the effect of prior lamivudine (3TC) treatment and other factors on HBV DNA suppression with TDF in a multisite clinical cohort of coinfected patients. We studied all patients enrolled in the Centers for AIDS Research Network of Integrated Clinical Systems cohort from 1996 to 2011 who had chronic HBV and HIV infection, initiated a TDF-based regimen continued for ≥ 3 months and had on-treatment HBV DNA measurements. We used Kaplan-Meier curves and Cox-proportional hazards to estimate time to suppression (HBV DNA level <200 IU/mL or <1000 copies/mL) by selected covariates. Among 397 coinfected patients on TDF, 91% were also on emtricitabine or 3TC concurrently, 92% of those tested were hepatitis B e antigen positive, 196 (49%) had prior 3TC exposure; 192 (48%) achieved HBV DNA suppression over a median of 28 months (interquartile range: 13-71). Median time to HBV DNA suppression was 17 months for those who were 3TC-naive and 50 months for those who were 3TC exposed. After controlling for other factors, prior 3TC exposure, baseline HBV DNA level >10,000 IU/mL, and lower nadir CD4 count were independently associated with decreased likelihood of HBV DNA suppression on TDF. These results emphasize the role of prior 3TC exposure and immune response on delayed HBV suppression on TDF.

Successful withdrawal of antiviral treatment in kidney transplant recipients with chronic hepatitis B viral infection

The optimal duration of antiviral therapy for kidney transplant recipients (KTR) with chronic hepatitis B virus (HBV) infection remains unclear. We reported the long-term outcomes after withdrawal of antiviral agent in KTR with chronic HBV infection. We retrospectively investigated the hepatitis B surface antigen (HBsAg)-positive KTR with antiviral agents between January 2002 and January 2012. Antiviral treatments were withdrawn in patients who met all of the following 7 criteria: (i) no clinical and histologic evidence of cirrhosis, (ii) normal liver biochemistry, (iii) negative for both HBV DNA and hepatitis B envelope antigen (HBeAg), (iv) no resistance to antiviral agent, (v) antiviral therapy > 9 months, (vi) maintenance dosage of immunosuppressant for > 3 months, and (vii) no history of acute rejection during recent 6 months. All patients were followed regularly at approximately 3-6 months for liver enzyme, viral markers, and HBV DNA level after antiviral withdrawal. Among a total of 445 KTR, 14 HBsAg-positive patients were included in this study. Antiviral agents were used, with lamivudine in 11 patients, and with adefovir, entecavir, and telbivudine in 3 patients, respectively. Discontinuation of antiviral agent was attempted in 6 (42.9%) of 14 patients who satisfied the criteria. The median duration of antiviral therapy before withdrawal was 14.3 months (range, 9-24months). Four (66.7%) of 6 patients were successfully withdrawn and remained negative for HBV DNA for a median 60.5months (range, 47-82months). The baseline HBV DNA level was not related to maintenance of remission after withdrawal. Two reactivated patients resumed antiviral treatment immediately, with subsequent normalization of HBV DNA. During the follow-up, 1 patient developed hepatocellular carcinoma; however, no patient death or graft failure was reported for all HBsAg-positive KTR. Antiviral therapy can be discontinued successfully and safely in selected KTR with chronic HBV infection, after complete suppression of HBV and sufficient duration of antiviral therapy.

Spontaneous reactivation of hepatitis B virus replication in an HIV coinfected patient with isolated anti-Hepatitis B core antibodies

Co-infections with HBV (hepatitis B virus) occur in HIV (human immunodeficiency virus) patients frequently. It has been reported that an effective treatment of HIV can also lead to a suppression of HBV and to anti-HBs seroconversion in HBV-infected patients. Here, we report a spontaneous reactivation of HBV replication in an HIV-infected patient with anti-HBc as the only marker of chronic HBV infection. The patient was known to be coinfected with HIV and HBV for years and the HBV DNA was measured repeatedly at low levels. A significant increase of HBV DNA up to 1.7x107 IU/ml was found accompanied with clinical symptoms of hepatitis. Multiple mutations occurred in the S gene during the flare-up of HBV as shown by sequencing, including I103T, K122R, M133I, F134V, D144E, V164E and L175S. Anti-HIV/HBV treatment led to a resolution of symptoms and to a decrease in the HIV RNA and HBV DNA viral load. It is possible that the accumulated mutations during HBV replication were selected and responsible for the reactivation.