The viral hepatitis B care cascade: A population-based comparison of immigrant groups.

BACKGROUND AND AIMS: The global burden of viral hepatitis B is substantial, and monitoring infections across the care cascade is important for elimination efforts. There is little information on care disparities by immigration status, and we aimed to quantify disease burden among immigrant subgroups. APPROACH AND RESULTS: In this population-based, retrospective cohort study, we used linked laboratory and health administrative records to describe the HBV care cascade in five distinct stages: (1) lifetime prevalence; (2) diagnosis; (3) engagement with care; (4) treatment initiation; and (5) treatment continuation. Infections were identified based on at least one reactive antigen or nucleic acid test, and lifetime prevalence was estimated as the sum of diagnosed and estimated undiagnosed cases. Care cascades were compared between long-term residents and immigrant groups, including subgroups born in hepatitis B endemic countries. Stratified analyses and multivariable Poisson regression were used to identify drivers for cascade progression. Between January 1997 and December 2014, 2,014,470 persons were included, 50,475 with infections, of whom 30,118 were engaged with care, 11,450 initiated treatment, and 6554 continued treatment >1 year. Lifetime prevalence was estimated as 163,309 (1.34%) overall, 115,722 (3.42%) among all immigrants, and 50,876 (9.37%) among those from highly endemic countries. Compared to long-term residents, immigrants were more likely to be diagnosed (adjusted rate ratio [aRR], 4.55; 95% CI, 4.46, 4.63), engaged with care (aRR, 1.07; 95% CI, 1.04, 1.09), and initiate treatment (aRR, 1.09; 95% CI, 1.03, 1.16). CONCLUSIONS: In conclusion, immigrants fared well compared to long-term residents along the care cascade, having higher rates of diagnosis and slightly better measures in subsequent cascade stages, although intensified screening efforts and better strategies to facilitate linkage to care are still needed.

The effect of hepatitis B virus on T lymphocyte and its subsets in chronic hepatitis B patients in different ALT stages: A new concept ALT in HBV infection.

The aim of the present study was to explore the effect of hepatitis B virus on T lymphocyte and its subsets in different ALT states, and elucidate the immunological mechanism of ALT basing antiviral therapy for hepatitis B. 363 chronic hepatitis B patients were selected as the study subjects. According to ALT abnormalities, the patients were divided into three study groups. ALT normal group 131 cases, normal≦ ALT < 2 times of upper limit group 110 cases, ALT ≥ 2 times of upper limit group 122 cases. Entecavir was given to the ALT ≥ 2 times of upper limit group patients and followed up for 24 weeks. The hepatitis B antigen antibody parameters were measured by chemiluminescence immunoassay analyzer, the liver function parameters were measured by automatic biochemical analyzer, the hepatitis B virus load were measured by quantitative PCR analyzer, T lymphocytes were detected by flow cytometry, the level of IL-2, IFN-γ, IL-4 and IL-10 were detected by enzyme-linked immunosorbent assay. Detecting the influence of different hepatitis B viru loads in different groups on immunological indexes, and the virological and immunological indexes changes in before and after antiviral therapy patients. In the ALT normal group, different virus load hepatitis B virus had minor effect on T lymphocytes and their subsets (P > 0.05). In the ALT ≥ double upper limit of normal group. with the virus load increased, The total number of T lymphocytes, CD3+ CD4 + T lymphocytes decreased, (P < 0.05)CD3+ CD8 + T lymphocytes increased(P < 0.05). With the virus load increased the cytokines IL-2, IFN-γ which reflect the Th1 lymphocytes increased(P < 0.05), the cytokines IL-4、IL-10 which reflect the Th2 lymphocytes decreased(P < 0.05). Before and after 24 weeks of entecavir treatment, the patient's HBV-DNA decreased significantly(P < 0.05) and the body's immune function improved significantly. (P < 0.05)The influence of hepatitis B virus on immune function is different in different ALT states. Therefore, the scientific significance of ALT grouping in the hepatitis B treatment can be clarified from the immunological point.

Natural History of Untreated HBeAg-Positive Chronic HBV Infection With Persistently Elevated HBV DNA but Normal Alanine Aminotransferase.

OBJECTIVES: Nucleos(t)ide analogues (NUCs) are not routinely recommended for patients with hepatitis B e antigen-positive chronic hepatitis B virus (HBV) infection who have persistently elevated serum HBV DNA level (>20,000 IU/mL) but normal alanine aminotransferase (<40 IU/L) level. Here, we evaluated the cumulative risks of hepatocellular carcinoma (HCC) in such patients (the untreated persistently elevated serum HBV DNA [pEDNA] group) compared with inactive carriers (the IC group). METHODS: Patients with untreated pEDNA (n = 126) and IC (n = 621) were enrolled between 2006 and 2012. Patients with cirrhosis or HCC at enrollment or a history of NUC treatment were excluded. RESULTS: The cumulative HCC risks at 5 and 9 years in the untreated pEDNA group were 1.1% and 1.9%, which were comparable with those of the IC group (P = 0.549). Inverse probability of treatment weighting and propensity score matching also showed similar HCC risks. In the untreated pEDNA group, there were no cases of HCC in the subgroup with serum HBV DNA level >1,000,000 IU/mL (immune-tolerant phase), which was significantly (P = 0.002) different compared with those with an intermediate serum HBV DNA level (20,000-1,000,000 IU/mL). DISCUSSION: The cumulative HCC risk in the untreated pEDNA group was minimal and comparable with that of the IC group. Further studies are required to determine whether early NUC treatment, indeed, reduces the HCC risk in patients with an intermediate serum HBV DNA level.

Serum Mac-2 binding protein glycosylation isomer level predicts hepatocellular carcinoma development in E-negative chronic hepatitis B patients.

BACKGROUND: Liver cirrhosis is a major risk factor for hepatocellular carcinoma (HCC) development in chronic hepatitis B (CHB). Serum Mac-2 binding protein glycosylation isomer (M2BPGi) is a novel serological marker for fibrosis. The role of M2BPGi in prediction of HCC is unknown. AIM: To examine the role of serum M2BPGi in predicting HCC development in hepatitis B e antigen (HBeAg)-negative patients. METHODS: Treatment-naive CHB patients with documented spontaneous HBeAg seroconversion were recruited. Serum M2BPGi was measured at baseline (within 3 years from HBeAg seroconversion), at 5 years and 10 years after HBeAg seroconversion and expressed as cut-off index (COI). Multivariate cox regression was performed to identify predictors for HCC development. ROC analysis was used to determine the cut-off value of M2BPGi. RESULTS: Among 207 patients (57% male, median age at HBeAg seroconversion 40 years old) with median follow-up of 13.1 (11.8-15.5) years, the cumulative incidence of HCC at 15 years was 7%. Median M2BPGi levels were significantly higher in patients with HCC compared to those without HCC (baseline: 1.39 COI vs 0.38 COI, P < 0.001; 5-year: 1.45 COI vs 0.47 COI, P < 0.001; 10-year: 1.20 COI vs 0.55 COI, P = 0.001). Multivariate analysis revealed age at HBeAg seroconversion [odds ratio (OR) = 1.196, 95% confidence interval (CI): 1.034-1.382, P = 0.016] and baseline M2BPGi (OR = 4.666, 95%CI: 1.296-16.802, P = 0.018) were significant factors predictive of HCC. Using a cut-off value of 0.68 COI, baseline M2BPGi yielded AUROC of 0.883 with 91.7% sensitivity and 80.8% specificity. CONCLUSION: High serum M2BPGi within 3 years after HBeAg seroconversion was a strong predictor for subsequent HCC development in treatment-naive HBeAg-negative CHB patients.

The Easy Liver Fibrosis Test (eLIFT) for predicting advanced liver fibrosis in patients with chronic hepatitis B.

OBJECTIVE: The easy liver fibrosis test (eLIFT) is a novel index to assess advanced liver fibrosis in chronic liver diseases. We aimed to investigate the diagnostic accuracy of eLIFT for advanced liver fibrosis in patients with chronic hepatitis B (CHB). METHODS: A total of 294 CHB patients with liver biopsy were enrolled. The diagnostic accuracy of eLIFT for advanced liver fibrosis was evaluated and compared to aspartate aminotransferase-to-platelet ratio index (APRI), fibrosis-4 score (FIB-4), gamma-glutamyl transpeptidase-to-platelet ratio (GPR), and red cell distribution width-to-platelet ratio (RPR) by ROC curves. RESULTS: The area under ROC curves (AUROCs) of eLIFT in predicting advanced fibrosis were 0.687 (95%CI 0.621 to 0.753), 0.714 (95%CI 0.631 to 0.798), and 0.633 (95%CI 0.522 to 0.744) in the entire cohort of CHB patients, HBeAg positive CHB patients, and HBeAg negative CHB patients, respectively. The optimal cut-off values of eLIFT for predicting advanced fibrosis in these three groups were 9.5. The eLIFT, as an easy-to-use scoring system, was comparable with APRI, FIB-4, GPR, and RPR in identifying advanced fibrosis in both HBeAg positive CHB and HBeAg negative CHB patients. CONCLUSIONS: eLIFT as a novel index can predict advanced liver fibrosis with a moderate sensitivity and accuracy in CHB patients. eLIFT, though having similar diagnostic values of advanced liver fibrosis compared to more complex existing tools such as APRI, FIB-4, GPR, and RPR in CHB patients, has the advantage of clarity of generation and ease of application and has the potential of being widely used by hepatologists.

An Assessment of Upper Limits of Normal for ALT and the Impact on Evaluating Natural Course of Chronic Hepatitis B Virus Infection in Chinese Children.

BACKGROUND: The current upper limits of normal (ULN) for serum alanine aminotransferase (ALT) are increasingly challenged. We aimed to re-evaluate the ULN for ALT and assess the potential impact on the classification of natural course of chronic hepatitis B virus (HBV) infection in children. METHODS: Laboratory data obtained from three hospitals in China were retrospectively analysed. In total, 2054 children with chronic HBV infection and 8149 healthy children at age ≤18 years were included in the study. RESULTS: Age-specific and gender-specific ULNs for ALT, at averages of 30 U/L for boys and 24 U/L for girls, were calculated from the data of healthy children. Using the revised ULNs vs. the current ULNs (40-50 U/L), 31-60% vs. 9-17% of the 2054 HBV-infected children had an abnormal result as seen in their ALT baseline analysis, and the highest abnormality rate was seen in the infants. Data of 516 HBV-infected children were applied for the classification of clinical phase, 28.8% vs. 19.8% of the children were classified into the phases of hepatitis B e antigen (HBeAg-)positive/negative hepatitis. During a median follow-up of 62 months, 39 of 153 children underwent HBeAg seroconversion, whereas 3 of them had persistently "normal" ALT, according to the current ULN. CONCLUSIONS: The revision of ULN for ALT in children substantially impacts the classification of the natural course of chronic HBV infection. Mild ALT fluctuation is common during the stage childhood, suggesting a need to rethink the current conceptions of immune tolerance and natural course of chronic HBV infection in the children.

Development of tenofovir disoproxil fumarate resistance after complete viral suppression in a patient with treatment-naïve chronic hepatitis B: A case report and review of the literature.

Tenofovir disoproxil fumarate (TDF) is a potent nucleotide analogue that is recommended as first-line therapy for patients with chronic hepatitis B. The results of a longitudinal study of TDF treatment demonstrated no development of resistance. We observed one treatment-naïve chronic hepatitis B (CHB) patient who developed TDF resistance after complete viral suppression during long-term TDF treatment. A 37-year-old HBeAg-positive man received TDF 300 mg/d for 43 mo. The hepatitis B virus (HBV) DNA titer was 8 log10 copies/mL at baseline and became undetectable at 16 mo after treatment. However, the HBV DNA titer rebounded to 7.5 log10 copies/mL at 43 mo after treatment. We performed full sequencing to find mutation sites associated with virologic breakthrough. The results showed 9 mutation sites, most of which had not been well-known as mutation sites. We changed the therapy from tenofovir to entecavir with a regimen of 0.5 mg once daily. After 4 mo, the HBV DNA titer decreased to 267 copies/mL, and the liver enzyme levels were normalized.

Detection of hyper-conserved regions in hepatitis B virus X gene potentially useful for gene therapy.

AIM: To detect hyper-conserved regions in the hepatitis B virus (HBV) X gene (HBX) 5' region that could be candidates for gene therapy. METHODS: The study included 27 chronic hepatitis B treatment-naive patients in various clinical stages (from chronic infection to cirrhosis and hepatocellular carcinoma, both HBeAg-negative and HBeAg-positive), and infected with HBV genotypes A-F and H. In a serum sample from each patient with viremia > 3.5 log IU/mL, the HBX 5' end region [nucleotide (nt) 1255-1611] was PCR-amplified and submitted to next-generation sequencing (NGS). We assessed genotype variants by phylogenetic analysis, and evaluated conservation of this region by calculating the information content of each nucleotide position in a multiple alignment of all unique sequences (haplotypes) obtained by NGS. Conservation at the HBx protein amino acid (aa) level was also analyzed. RESULTS: NGS yielded 1333069 sequences from the 27 samples, with a median of 4578 sequences/sample (2487-9279, IQR 2817). In 14/27 patients (51.8%), phylogenetic analysis of viral nucleotide haplotypes showed a complex mixture of genotypic variants. Analysis of the information content in the haplotype multiple alignments detected 2 hyper-conserved nucleotide regions, one in the HBX upstream non-coding region (nt 1255-1286) and the other in the 5' end coding region (nt 1519-1603). This last region coded for a conserved amino acid region (aa 63-76) that partially overlaps a Kunitz-like domain. CONCLUSION: Two hyper-conserved regions detected in the HBX 5' end may be of value for targeted gene therapy, regardless of the patients' clinical stage or HBV genotype.

Confirmation of specificity of reactivity in a solid phase ELISA for the detection of hepatitis E viral antigen improves utility of the assay.

Genotype 3 hepatitis E virus (HEV) can lead to persistent infections in immunocompromised hosts. A recently available commercial assay for the detection of HEV antigen (HEV-Ag ELISA, Wantai diagnostics) may enable the study of HEV-Ag dynamics in such persistent infections, however currently there is no confirmatory test available. We generated a putative neutralising reagent from a pool of four convalescent blood donor samples and explored neutralising activity against HEV antigens from clinical samples, HEV tissue-culture and virus-like particles. Using this neutralisation method we were able to differentiate true reactivity from non-specific reactivity in plasma, stool and urine samples. This could also facilitate the introduction of HEV-Ag detection as a screening assay or the study of HEV-Ag in different body fluids.

Ultrasensitive electrochemical immunosensor for quantitative detection of HBeAg using Au@Pd/MoS2@MWCNTs nanocomposite as enzyme-mimetic labels.

A sensitive sandwich-type electrochemical immunosensor for the detection of hepatitis B e antigen (HBeAg) was successfully developed based on the gold@palladium nanoparticles (Au@Pd NPs) loaded by molybdenum disulfide functionalized multiwalled carbon nanotubes (Au@Pd/MoS2@MWCNTs). The resultant nanocomposites not only possessed high specific surface area and good biocompatibility, but also exhibited excellent electro-catalytical property. Au NPs functionalized porous graphene oxide (p-GO@Au) were used as sensing platforms and primary antibodies carriers, which can accelerate the electron transfer and improve the load capacity of primary antibodies (Ab1), improving the sensitivity of the immunosensor. Under optimal conditions, the designed immunosensor could detect target HBeAg concentration in the range from 0.1pg/mL to 500pg/mL, with a low detection limit of 26fg/mL (S/N = 3) for HBeAg. Additionally, the designed immunosensor showed excellent specificity, good reproducibility and acceptable stability. The satisfactory results in analysis of human serum samples indicated that it had potential application in clinical monitoring of tumor markers.

Perinatal transmission in infants of mothers with chronic hepatitis B in California.

AIM: To evaluate maternal hepatitis B virus (HBV) DNA as risk for perinatal HBV infection among infants of HBV-infected women in California. METHODS: Retrospective analysis among infants born to hepatitis B surface antigen (HBsAg)-positive mothers who received post vaccination serologic testing (PVST) between 2005 and 2011 in California. Demographic information was collected from the California Department of Public Health Perinatal Hepatitis B Program databaseand matched to birth certificate records. HBV DNA level and hepatitis B e antigen (HBeAg) status were obtained from three large commercial laboratories in California and provider records if available and matched to mother infant pairs. Univariate analysis compared infected and uninfected infants. Multivariate analysis was restricted to infected infants and controls with complete maternal HBV DNA results using a predefined high HBV DNA level of > 2 × 107 IU/mL, a 5:1 ratio of cases to controls and a two-sided confidence level of 95%. RESULTS: A total of 17687 infants were born to HBsAg positive mothers in California between Jan 1 2005 and Dec 31, 2011. Among 11473 infants with PVST, only 125 (1.1%) were found to be HBV infected. Among these infected infants, lapses in Advisory Committee on Immunization Practices recommended post exposure prophylaxis (PEP) occurred in only 9 infants. However, PEP errors were not significantly different between infected and uninfected infants. Among the 347 uninfected and infected infants who had maternal HBeAg and HBV DNA level, case-control analysis found HBeAg positivity (70.4% vs 28.9%, OR = 46.76, 95%CI: 6.05-361.32, P < 0.001) and a maternal HBV DNA level ≥ 2 × 107 IU/mL (92.6% vs 18.5%, OR = 54.5, 95%CI: 12.22-247.55, P < 0.001) were associated with perinatal HBV infection. In multivariate logistic regression, maternal HBV DNA level ≥ 2 × 107 IU/mL was the only significant independent predictor of perinatal HBV infection. CONCLUSION: In California, transmission is low and most infected infants receive appropriate PEP and vaccination. Maternal HBV DNA ≥ 2 × 107 IU/mL is associated with high risk of perinatal infection.

miR-29a promotes hepatitis B virus replication and expression by targeting SMARCE1 in hepatoma carcinoma.

AIM: To investigate the functional role and underlying molecular mechanism of miR-29a in hepatitis B virus (HBV) expression and replication. METHODS: The levels of miR-29a and SMARCE1 in HBV-infected HepG2.2.15 cells were measured by quantitative real-time PCR and western blot analysis. HBV DNA replication was measured by quantitative PCR and Southern blot analysis. The relative levels of hepatitis B surface antigen and hepatitis B e antigen were detected by enzyme-linked immunosorbent assay. The Cell Counting Kit-8 (CCK-8) was used to detect the viability of HepG2.2.15 cells. The relationship between miR-29a and SMARCE1 were identified by target prediction and luciferase reporter analysis. RESULTS: miR-29a promoted HBV replication and expression, while SMARCE1 repressed HBV replication and expression. Cell viability detection indicated that miR-29a transfection had no adverse effect on the host cells. Moreover, SMARCE1 was identified and validated to be a functional target of miR-29a. Furthermore, restored expression of SMARCE1 could relieve the increased HBV replication and expression caused by miR-29a overexpression. CONCLUSION: miR-29a promotes HBV replication and expression through regulating SMARCE1. As a potential regulator of HBV replication and expression, miR-29a could be a promising therapeutic target for patients with HBV infection.

[Zinc finger E-box-binding homeobox 2 inhibits hepatitis B virus replication and expression].

Objective: To investigate the effect of zinc finger E-box-binding homeobox 2 (ZEB2) on hepatitis B virus (HBV) replication and expression. Methods: HepG2, HepG2.2.15, and HepAD38 cells were cultured separately, and Western blot was used to measure the expression of ZEB2. HepG2.2.15 cells were cultured and transfected with ZEB2 expression plasmids or shRNA targeting ZEB2. Western blot was used to measure the expression of ZEB2 and HBV core proteins, quantitative real-time PCR was used to measure HBV 3.5 kb RNA and HBV DNA, Southern blot was used to measure HBV replicative intermediate, and ELISA was used to measure the expression of HBsAg and HBeAg, in order to clarify the effect of ZEB2 on HBV replication and expression. The dual-luciferase reporter system was used to analyze the effect of ZEB2 on HBV promoter, and the chromatin immunoprecipitation assay was used to detect the binding of ZEB2 to HBV promoter. The t-test was used for comparison of means between groups. Results: The expression of ZEB2 was inhibited in the cells with HBV replication. Overexpression of ZEB2 reduced the level of HBV replication and expression by about 50% (P< 0.05). After ZEB2 was downregulated by shZEB2-1 or shZEB2-2, the level of HBV replicative intermediate increased from 58.53 ± 3.43 to 112.80 ± 5.03, and 128.30 ± 2.31, the relative expression level of HBV 3.5 kb RNA increased from 1.00 ± 0.01 to 2.03 ± 0.02 and 2.32 ± 0.03, the level of HBsAg increased from 35.63% ± 1.57% to 81.87% ± 0.43% and 100.00% ± 2.18%, and HBeAg increased from 37.00% ± 0.70% to 88.00% ± 2.60% and 100.00% ± 0.75%. Furthermore, ZEB2 could bind to HBV core promoter and inhibit its transcriptional activity. Conclusion: ZEB2 inhibits HBV replication and expression through binding to HBV core promoter and inhibiting its transcriptional activity.

[Role of glucose-6-phosphate dehydrogenase in hepatitis B virus replication and its possible mechanism of action].

OBJECTIVE: To investigate the role of glucose-6-phosphate dehydrogenase (G6PD) in hepatitis B virus (HBV) replication and its possible mechanism of action. METHODS: Tissue microarray, quantitative real-time PCR, and Western blot were performed to analyze the differences in G6PD expression levels in the HBV-positive and HBV-negative liver tissues, HepG2.2.15 cells, and HepG2 cells. The siRNA transfection technique was used to knock down G6PD gene in HepG2.2.15 cells for 48 hours. Chemiluminescence was used for HBsAg and HBeAg quantification in supernatant, and quantitative real-time PCR was used to measure HBV DNA, type I interferon (IFN), and downstream IFN-stimulated genes. The t-test was used for comparison between groups. RESULTS: G6PD expression was significantly upregulated in the HBV-positive liver tissues and cells compared with HBV-negative liver tissues and cells, and the stain intensity and immunohistochemical scores were 89.69±54.92 and 31.90±18.62, respectively (P < 0.05). After G6PD expression in HepG2.2.15 cells was interfered by siRNA, the quantitative levels of HBV DNA, HBsAg, and HBeAg in supernatant were reduced significantly, and the mRNA expression levels of IFNα1, IFNß1, and five downstream IFN-stimulated genes (OAS1, ISG15, OAS3, EIF2α, and PKR) increased significantly (all P < 0.05). CONCLUSION: G6PD plays a vital role in HBV replication, and its mechanism of action in regulating HBV replication may be related to type I IFN signaling pathway.

Complete hepatitis B virus prophylaxis withdrawal in hepatitis B surface antigen-positive liver transplant recipients after longterm minimal immunosuppression.

Tailored approaches have been attempted to prevent hepatitis B virus (HBV) reinfection in antibodies against hepatitis B surface antigen (HBsAg)-positive liver transplantation (LT) recipients in order to minimize the use of hepatitis B immune globulin (HBIG) and nucleoside analogues (NAs). We report the results of complete HBV prophylaxis withdrawal after a follow-up of at least 6 years in LT recipients with undetectable serum HBV DNA and intrahepatic total HBV DNA and covalently closed circular DNA at LT. We included 30 HBsAg positive, hepatitis B e antigen-negative recipients, 6 with hepatitis C virus and 7 with hepatitis D virus coinfection, who had received HBIG plus NA for at least 5 years after LT. Stepwise HBIG and NA withdrawal was performed in two 6-month periods under strict monitoring of HBV virology. All patients underwent a clinical, biochemical, and virological follow-up at 3-6 month intervals. HBV recurrence (HBsAg seroreversion ± detectable HBV DNA) occurred in 6 patients: in 1 patient after HBIG interruption and in 5 after both HBIG and NA cessation. Only 3 patients required reinstitution of HBV prophylaxis because of persistent HBV replication, and all achieved optimal control of HBV infection and did not experience clinical events. The other who recurred showed only short-lasting HBsAg positivity, with undetectable HBV DNA, followed by spontaneous anti-HBs seroconversion. An additional 15 patients mounted an anti-HBs titer, without previous serum HBsAg detectability. At the end of follow-up, 90% of patients were still prophylaxis-free, 93.3% were HBsAg negative, and 100% were HBV DNA negative; 60% had anti-HBs titers >10 IU/L (median, 143; range, 13-1000). This small series shows that complete prophylaxis withdrawal is safe in patients transplanted for HBV-related disease at low risk of recurrence and is often followed by spontaneous anti-HBs seroconversion. Further studies are needed to confirm this finding. Liver Transplantation 22 1205-1213 2016 AASLD.

[Effect of the cytoplasmic DNA sensor DAI on replication of hepatitis B virus].

OBJECTIVE: To explore the effect of the cytoplasmic DNA sensor DAI on replication of hepatitis B virus (HBV) and its possible mechanism. METHODS: The hepatocyte-derived cell line HepG2 was co-transfected with DAI siRNA and the HBV1.3 replicative plasmid PHY106, and the cells were divided into two experimental groups. Six hours later, total RNA was extracted from the first group of cells and expression of IFIT1 and IL-6 were detected by real-time RT-PCR. The second group of cells was incubated for 4 days, after which the cell supernatant was collected and the HBV surface antigen (HBsAg) and envelope antigen (HBeAg) were detected by ELISA. In addition, HBV core particles were extracted and applied to southern blot assay to detect the intracellular HBV replication intermediates (rcDNA, dlDNA and ssDNA). Next, the HepG2 cells were triple transfected with siRNA targeting the type I interferon pathway molecule TBK1 and DAI simultaneously and HBV1.3, after which HBV viral proteins were detected. Two-group comparisons were made using the independent sample t-test, and more-than-2-group comparisons were made using ANOVA. RESULTS: DAI gene expression was down-regulated in response to DAI siRNA transfection. Cells with down-regulated DAI showed inhibited HBV replication (in a dose-dependent manner), accompanied by reduced levels of HBsAg (0.0195+/-0.0050 vs. CONTROL: 0.3150+/-0.0200, P less than 0.05, t = 14.77) and HBeAg (0.0140+/-0.0040 vs. CONTROL: 0.01235+/-0.0135, P less than 0.05, t = 7.777). No effect of down-regulated DAI was observed for the expression of IFIT1 of IL-6. siRNA-mediated down-regulation of TBK1 and DAI simultaneously led to reduced expression of HBsAg and HBeAg. CONCLUSION: Down-regulation of DAI gene expression inhibited HBV replication and HBV protein expression, but the underlying mechanism was not related to the type I interferon or NF-kB signaling pathway.

An aptamer targets HBV core protein and suppresses HBV replication in HepG2.2.15 cells.

Hepatitis B virus (HBV)-related hepatitis is a major health concern worldwide. As current anti-HBV therapies are limited, it is essential to develop new strategies. Aptamer, a newly developed adaptive molecule (single-strand DNA or RNA also known as nucleotide antibody), is a new strategy for clinical diagnosis and therapy due to its high affinity and specificity. In the present study, by systematic evolution of ligand by exponential enrichment (SELEX), aptamers were screened against the core protein of HBV (HBc) from a random ssDNA library. Quantitative PCR (qPCR) results showed that the binding proportions of the SELEX-enriched aptamer pools were increased with the SELEX rounds, until round seven. Thus, the pool of round seven was cloned. Following the sequence analysis of a total of 90 clones by Macaw software, five aptamer candidates were selected and their affinity to HBc was tested by dot blot. Apt.No.28, which had sequence replicates in the clones, was shown to have a high affinity. Furthermore, by agarose gel electrophoresis-capillary transfer-blotting and qPCR, Apt.No.28 was shown to inhibit the assembly of the nucleocapsid, reducing extracellular HBV DNA whose synthesis relied on the formation of the nucleocapsid, indicating its role in suppressing HBV replication. The results provided a new ideal targeting molecule and may facilitate the strategy for targeted therapy as well as drug development of HBV-related diseases.

Hepatitis B virus e antigen induces activation of rat hepatic stellate cells.

Chronic hepatitis B virus infection is a major cause of hepatic fibrosis, leading to liver cirrhosis and hepatocellular carcinoma. Hepatitis B virus e antigen (HBeAg) is an accessory protein of HBV, not required for viral replication but important for natural infection in vivo. Hepatic stellate cells (HSCs) are the major producers of excessive extracellular matrix during liver fibrogenesis. Therefore, we examined the influence of HBeAg on HSCs. The rat HSC line HSC-T6 was transfected with HBeAg plasmids, and expression of α-smooth muscle actin, collagen I, transforming growth factor-ß1 (TGF-ß), and tissue inhibitors of metalloproteinase 1 (TIMP-1) was investigated by quantitative real-time PCR. The proliferation of HSCs was determined by MTS analysis. HBeAg transduction induced up-regulation of these fibrogenic genes and proliferation of HSCs. We found that HBeAg induced TGF-ß secretion in HSCs, and the activation of HSCs was prevented by a neutralizing anti-TGF-ß antibody. Depletion and addition of HBeAg protein in conditioned medium from HSC-T6 cells transduced with HBeAg indicated that HBeAg directly induced the activation and proliferation of rat primary HSCs. Taken together, HBeAg induces the activation and proliferation of HSCs, mainly mediated by TGF-ß, and HBeAg protein purified from cell medium can directly activate HSCs.

Successful establishment and evaluation of a new animal model for studying the hepatitis B virus YVDD mutant.

The treatment of infection with lamivudine-resistant mutants of hepatitis B virus (HBV) with mutations in the YMDD motif has become a crucial issue in the clinic. In this work, the plasmids pcDNA3.1 (+)-HBV/C-YVDD and pcDNA3.1 (+)-HBV/C-YMDD were constructed and injected into BALB/c mice using a hydrodynamics-based procedure to investigate viral replication and expression of HBV lamivudine-resistant YVDD mutants in vivo. Compared with the YMDD group, HBsAg levels were higher in sera of mice in the YVDD group, but HBeAg levels were lower on day 1 after injection. Levels of HBcAg in hepatocytes were higher in the YVDD group on day 1, whereas the HBsAg levels were lower. The levels of HBV mRNA in the liver were higher in mice in the YVDD group on day 1 after injection. The results showed that injection with these plasmids resulted in efficient initiation of replication of HBV in mice and also suggested that the combined mutations in YVDD mutants could affect the replication process.

Inhibition of duck hepatitis B virus infection of liver cells by combined treatment with viral e antigen and carbohydrates.

The e antigen (eAg) of duck hepatitis B virus (DHBV) is a glycosylated secretory protein with a currently unknown function. We concentrated this antigen from the supernatants of persistently infected primary duck liver cell cultures by ammonium sulphate precipitation, adsorption chromatography over concanavalin A Sepharose, preparative isoelectric focusing and molecular sieve chromatography. The combined treatment of duck liver cells with DHBV eAg (DHBe) concentrate and alpha-methyl-d-mannopyranoside strongly inhibited DHBV replication at de novo infection. When DHBe was added to non-infected primary duck liver cells, it was found to be associated with liver sinusoidal endothelial cells. This binding could be inhibited by the addition of alpha-methyl-d-mannopyranoside and other sugar molecules. The inhibitory effect of DHBe on infection could play a role in maintaining viral persistence.