Expression and purification of Hepatitis B virus core antigen using Escherichia coli and its utilization for the diagnosis of Hepatitis B virus infections.

Hepatitis B virus (HBV) is responsible for most of the viral hepatitis worldwide. HBV is a partially double stranded DNA virus that is composed of four main open reading frames (ORFs) encoding its important antigens, namely hepatitis B surface antigen (HBsAg), hepatitis B core antigen (HBcAg), HBV polymerase and hepatitis B X antigen (HBxAg). In this study, we report a successful method for the cloning and expression of HBcAg. The ORF of HBcAg was successfully amplified using polymerase chain reaction (PCR), cloned into the expression vector pRSET-B and transformed to Escherichia coli (E. coli) BL-21 (DE3) pLysS strain for protein expression. Successful expression of HBcAg was accomplished, in which an induced protein with a molecular weight of 24 kDa was obtained and confirmed by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Western blotting. The produced HBcAg was successfully used for the diagnosis of HBV infected patient through detection of antibodies against HBcAg (anti-HBcAg) in the serum of the patient utilizing Western blotting. Overall, this study provides a simple, convenient and efficient protocol for the production of HBcAg that can be used as an important candidate to study the diagnosis and prognosis of HBV disease, as well as for understanding the epidemiological prevalence of HBV cases and production of anti-HBcAg.

Principais motivos de descarte de córneas para transplante na Paraíba: por que o anti-HBc merece atenção?* / Main reasons for discarding corneas for transplant in Paraíba: why does anti-HBc deserve attention?*

RESUMO Objetivo: Identificar o perfil dos doadores de tecidos oculares humanos na área de atuação do Banco de Olhos da Paraíba, destacando o impacto da sorologia positiva para hepatite B no descarte dos tecidos para transplante. Métodos: O estudo é transversal e utilizou dados do Banco de Olhos da Paraíba entre janeiro de 2013 e dezembro de 2022. Dados sobre procedência, idade, sexo, causa do óbito, tempo entre óbito e enucleação, resultados sorológicos e motivo de descarte das córneas dos doadores foram coletados. Resultados: O maior motivo de descarte foi por sorologia positiva (56,5%), sendo positivadas as sorologias positivas para hepatite B e HBsAg em 11,1% e 4,75% dos pacientes, respectivamente. Conclusão: A sorologia positiva para hepatite B como um critério de descarte absoluto é responsável por grande parcela de descartes, apesar da pouca informação sobre suas repercussões e representação de infectividade nos receptores do transplante.

ABSTRACT Objective: To identify the profile of human ocular tissue donors in the area covered by the Eye Bank of Paraíba (PB), highlighting the impact of positive serology for hepatitis B (anti-HBc) in the disposal of tissues for transplantation. Methods: This is a cross-sectional that uses data from the Eye Bank of Paraíba (PB) between January 2013 and December 2022. Data on origin, age, sex, cause of death, time between death and enucleation, serological results, and reason for discarded donor corneas were collected. Results: The main reason for discarding was due to positive serology (56.5%), with positive anti-HBc and HBsAg serology in 11.1% and 4.75% of patients, respectively. Conclusion: Anti-HBc positive serology as an absolute disposal criterion is responsible for great part of disposals, despite little information about its repercussions and representation of infectivity in transplant recipients.

Evaluation of the in situ assay for HBV DNA: An observational real-world study in chronic hepatitis B.

ABSTRACT: The visualization of intrahepatic hepatitis B virus (HBV) DNA by in situ hybridization (ISH) has uncovered some interesting aspects of HBV life cycle at the single-cell level. In the current study, we intend to evaluate the reliability and robustness of this assay in the real-world clinical scenario and its relationship with currently available clinical biomarkers in chronic hepatitis B (CHB) patients.In this cross-sectional study, 94 CHB patients and 10 patients with non-HBV related liver diseases were enrolled. Liver biopsies and routine histopathology analysis were performed. Intrahepatic HBV DNA and viral antigens (HBsAg and HBcAg) were detected by ISH and immunohistochemistry (IHC), respectively. The basic biochemical and virological parameters such as alanine transaminase, serum HBV DNA, and serum HBsAg were measured.The HBV DNA-ISH assay showed 55.8% (53/94 cases) positive rate in CHB patients, no false positive was found in non-HBV related hepatitis. The IHC of HBsAg and HBcAg showed a positive rate of 94.7% (89/94 cases) and 19.5% (17/87 cases), respectively. Quantification of HBV DNA-ISH signal showed a significant correlation with serum HBV DNA (rs = 0.6223, P < .0001). In addition, the staining pattern of HBV DNA in situ in the context of collagen deposition informed the histopathological progression of chronic liver disease.The application of this ISH assay in evaluating intrahepatic viral replication in real-world CHB patients showed favorable performance. It can be a complementation to conventional liver histopathology examination and IHC detection of viral antigens. This methodology provides an intuitive assessment of virological and pathological state of CHB patients, and further supports clinical diagnosis and management.

High Frequency Occult Hepatitis B Virus Infection Detected in Non-Resolved Donations Suggests the Requirement of Anti-HBc Test in Blood Donors in Southern China.

Background: Most Chinese Blood Centers adopted mini pool (MP) nucleic acid testing (NAT) for HBV screening due to high cost of Individual donation (ID) NAT, and different proportions of MP-reactive but ID-non-reactive donations (MP+/ID-, defined as non-resolved donations) have been observed during daily donor screening process. Some of these non-resolved donations are occult HBV infections (OBIs), which pose potential risk of HBV transmission if they are not deferred. This study is aimed to further analyze these non-resolved donations. Methods: The non-resolved plasma samples were further analyzed by serological tests and various HBV DNA amplification assays including quantitative PCR (qPCR) and nested PCR amplifying the basic core and pre-core promoter regions (BCP/PC; 295 base pairs) and HBsAg (S) region (496 base pairs). Molecular characterizations of HBV DNA+ non-resolved samples were determined by sequencing analysis. Results: Of 17,226 MPs from 103,356 seronegative blood donations, 98 MPs were detected reactive for HBV. Fifty-six out of these 98 (57.1%) reactive MPs were resolved as HBV DNA+, but the remaining 42 pools (42.9%, 252 donations) were left non-resolved with a high rate (53.2%) of anti-HBc+. Surprisingly, among 42 non-resolved MPs, 17 contained one donation identified as OBIs by alternative NAT assays. Sequence analysis on HBV DNAs extracted from these OBI donations showed some key mutations in the S region that may lead to failure in HBsAg detection and vaccine escape. Conclusion: A total of 53.2% of the non-resolved donations were anti-HBc+, and OBIs were identified in 40.5% of these non-resolved pools. Therefore, non-resolved donations with anti-HBc+ might pose potential risk for HBV transmission. Our present analysis indicates that anti-HBc testing in non-resolved donations should be used to identify OBIs in order to further increase blood safety in China.

HBcrAg and pg RNA and the therapeutic effect in HBeAg-positive patients receiving anti-viral therapy, baseline serum HBV-RNA is a powerful predictor of response.

We used HBV core antigen (HbcrAg), pre-genomic RNA (pg RNA) and other biomarkers to evaluate the therapeutic effect in HBV infected patients receiving anti-viral therapy. 127HBeAg-positive patients were enrolled: 35 patients received nucleotide therapy, 14 patients received interferon and 78 patients received combination therapy with both. HBcrAg, pg RNA and other biomarkers were detected at different time points, we defined the decreased titre of HBcrAg and HBeAg from baseline to 6 and baseline to 12 months as ∆HBcrAg and ∆HBeAg, which were used to predict HBeAg seroconversion. Furthermore, we used the time-dependent receiver operator curve of different markers to analyse HBeAg seroconversion. For HBeAg seroconversion: at 6 months, 0.75 log10 U/mL of ∆HBcrAg and 1.47 log10 PEI U/mL of ∆HBeAg showed maximum predictive value in receiver operator curve analysis (Youden's index values for area under the curve of 0.687 and 0.646, respectively). At 12 months, 2.05 log10 U/mL of ∆HBcrAg and 1.92 log10 PEI U/mL of ∆HBeAg showed improved prediction (maximum Youden's index values, with areas under the curve of 0.688 and 0.698, respectively).pg RNA was a better predictor of outcome due and the concentrations of 6.20 log10 I U/mL of pg RNA and 8.0 log10 U/mL of HBcrAg were cut-off values for response in a Kaplan-Meier curve analysis. Our results may be used to identify the pg RNA concentration in patients at baseline and ∆HBcrAg during therapy who are likely to achieve HBeAg seroconversion according to the cut-off value at different time points, thus helping to evaluate the therapeutic effect.

Anti-HBc impacts on the risk of hepatitis B reactivation but not on survival of solid-organ transplant recipients.

Immunosuppression can lead to hepatitis B virus (HBV) reactivation in hepatitis B core antigen antibodies (anti-HBc) positive patients, especially those undergoing chemotherapy, although there is limited data on solid organ recipients, especially lung transplantation. Our aim was to analyze the risk of HBV reactivation and the potential impact of anti-HBc-positive status (both donors and recipients) on prognosis in a lung, kidney, and liver transplantation cohort.Retrospective analysis including data from all transplants in adults (2011-2012) in a tertiary hospital, with prospective HBV serology study to assess the risk of reactivation and its possible impact on survival.In total, 392 transplant recipients were included (196 kidney, 113 lung, 83 liver). Pre-transplantation anti-HBc screening was more frequent in liver recipients (P < .001) and donors (P < .001) than in kidney or lung. Fifty-five (14%) recipients were anti-HBc-positive and were not undergoing antiviral prophylaxis. Three (5.4%) cases of HBV reactivation occurred: 2 in pre-transplant anti-HBc-positive recipients and 1 with prior unknown anti-HBc status. All were HBeAg+ with HBV deoxyribonucleic acid (DNA) >10E8 IU/mL and only mild fibrosis. Baseline recipient anti-HBc positive status was the only factor associated with HBV reactivation. No reactivation cases occurred in lung or kidney recipients of anti-HBc positive grafts. Survival was lower in lung transplants, especially in human immunodeficiency virus-infected patients and those with prior immunosuppression.Anti-HBc positive status is a risk factor for HBV reactivation in solid organ recipients. Anti-HBc testing is highly recommended in solid-organ transplant recipients in order to identify those anti-HBc positive and therefore candidates for periodical hepatitis B surface antigen (HBsAg) and HBV DNA screening after transplant.

The role of hepatitis B core-related antigen in predicting hepatitis B virus recurrence after liver transplantation.

BACKGROUND: Hepatitis B core-related antigen (HBcrAg) is a viral marker for the development of cirrhosis and hepatocellular carcinoma (HCC) in patients with chronic hepatitis B (CHB). However, the relationship between HBcrAg and HBV recurrence after liver transplantation (LT) is unclear. AIM: To investigate the correlation of serum HBcrAg level with HBV recurrence post-LT to evaluate the prognostic role of the pre-LT HBcrAg level. METHODS: This retrospective cohort study enrolled 357 CHB patients who received LT for a median of 36.6 months. Univariate and multivariate analyses and time-dependent receiver operating characteristic (ROC) curves for markers associated with HBV recurrence were analysed. RESULTS: 48 patients (13.4%) had HBV recurrence after LT. HBcrAg, detectable HBV DNA, HCC and HCC recurrence were associated with HBV recurrence. In a multivariate analysis, HBcrAg level was independently associated with HBV recurrence, and the relationship between HBcrAg level and incident HBV recurrence was significant and graded (HR: 3.17 per unit; 95% CI: 1.97-5.11; P for trend < .001). Additionally, HBcrAg level was superior to HBV DNA level in predicting HBV recurrence by time-dependent ROC analysis. Patients with an HBcrAg ≥ 5.0 log U/mL had a significantly higher 5-year cumulative recurrence rate than those with an HBcrAg < 5.0 log U/mL (37.6% vs 6%, P < .001); the adjusted hazard ratio was 5.27 (95% CI 2.47-11.25, P < .001). CONCLUSION: An elevated serum HBcrAg level was independently associated with the risk of HBV recurrence in patients with CHB after LT.

[Recent advances in understanding and diagnosing hepatitis B virus infection]. / Progrès récents dans la compréhension et le diagnostic de l'infection chronique par le virus de l'hépatite B.

Hepatitis B virus (HBV) infects approximately 257 million individuals worldwide. Recent advances in the virology and diagnosis of HBV infection are summarized in this review article. A novel classification of the different phases of chronic HBV infection, proposed by the European Association for the Study of the Liver (EASL), is presented. New diagnostic and monitoring tools are now available, including rapid diagnostic tests for hepatitis B surface antigen (HBsAg) detection, HBsAg quantification assays, an HBV core-related antigen (HBcrAg) quantification test, and HBV RNA quantification testing. Their clinical utility under study is discussed in this review.

Liver transplantation using hepatitis B core positive grafts with antiviral monotherapy prophylaxis.

BACKGROUND & AIMS: The impact of hepatitis B core antibody (anti-HBc) positive liver grafts on survival and the risk of de novo hepatitis B virus (HBV) infection after liver transplantation (LT) remain controversial. Therefore, we aimed to analyze this risk and the associated outcomes in a large cohort of patients. METHODS: This was a retrospective study that included all adults who underwent LT at Queen Mary Hospital, Hong Kong, between 2000 and 2015. Data were retrieved from a prospectively collected database. Antiviral monotherapy prophylaxis was given for patients receiving grafts from anti-HBc positive donors. RESULTS: A total of 964 LTs were performed during the study period, with 416 (43.2%) anti-HBc positive and 548 (56.8%) anti-HBc negative donors. The median follow-up time was 7.8 years. Perioperative outcomes (hospital mortality, complications, primary nonfunction and delayed graft function) were similar between the 2 groups. The 1-, 5- and 10-year graft survival rates were comparable in anti-HBc positive (93.3%, 85.3% and 76.8%) and anti-HBc negative groups (92.5%, 82.9% and 78.4%, p = 0.944). The 1-, 5- and 10-year patient survival rates in anti-HBc positive group were 94.2%, 87% and 79% and were similar to the anti-HBc negative group (93.5%, 84% and 79.7%, p = 0.712). One-hundred and eight HBsAg negative recipients received anti-HBc positive grafts, of whom 64 received lamivudine and 44 entecavir monotherapy prophylaxis. The risk of de novo HBV was 3/108 (2.8%) and all occurred in the lamivudine era. There were 659 HBsAg-positive patients and 308 (46.7%) received anti-HBc positive grafts. The risk of HBV recurrence was similar between the 2 groups. Donor anti-HBc status did not impact on long-term patient and graft survival, or the risk of hepatocellular carcinoma recurrence after LT. CONCLUSIONS: De novo HBV was exceedingly rare especially with entecavir prophylaxis. Anti-HBc positive grafts did not impact on perioperative and long-term outcomes after transplant. LAY SUMMARY: The risk of de novo hepatitis B infection after liver transplantation was rare when using hepatitis B core positive liver grafts with entecavir monotherapy prophylaxis. Hepatitis B core antibody status did not impact on perioperative and long-term outcomes after liver transplantation. This provides support for the clinical use of hepatitis B core positive liver grafts when required.

A label-free and reagentless immunoelectrode for antibodies against hepatitis B core antigen (anti-HBc) detection.

An electrochemical immunosensor devoted the core hepatitis B antibody detection, based on polytyramine (PTy) and carbon nanotubes (CNT) composite was developed. The antibody interactions with immobilized antigens were detected by reduction on the electron transfer from ionic species coming from reactive amine groups of PTy. The synthesis in acid medium of PTy-CNT composite favorite a great amount of NH3+ ionic species, forming a nanocomposite with high catalytic activity on the electrode surface. As proof-of-concept, antibodies against the core hepatitis B virus were label-free and reagentless electrochemically detected by square wave voltammetry (SWV) through decrease on cathodic peaks. It was recently reported that hepatitis B core antigen antibodies (anti-HBc) is a powerful biomarker for hepatitis B virus (HBV) infection, being more specific than HBsAg due to the possibility of detecting the occult HBV infections. The nanostructured film was characterized by atomic force microscopy and electrochemical techniques. This immunosensor showed linear responses from 1.0 to 5.0 ng mL-1 and a limit of detection of 0.89 ng mL-1 anti-HBc. It was also tested in assays with negative and positive blood samples using 0.1 M KCl as electrolyte support on readings showing specific responses. This easy reagentless detection platform, showing a remarkable potential to development of bolder and simpler HBV assay for screening of blood bags, in attempting to circumvent point-of-care testing limitations.

Screening for Hepatitis B: Serology Markers Interpretation.

Occupational health nurses (OHNs) need adequate knowledge to interpret the serology markers when screening workers for Hepatitis B virus.

Gold nanoparticle-decorated reduced-graphene oxide targeting anti hepatitis B virus core antigen.

Hepatitis B virus core antigen (HBcAg) is the major structural protein of hepatitis B virus (HBV). The presence of anti-HBcAg antibody in a blood serum indicates that a person has been exposed to HBV. This study demonstrated that the immobilization of HBcAg onto the gold nanoparticles-decorated reduced graphene oxide (rGO-en-AuNPs) nanocomposite could be used as an antigen-functionalized surface to sense the presence of anti-HBcAg. The modified rGO-en-AuNPs/HBcAg was then allowed to undergo impedimetric detection of anti-HBcAg with anti-estradiol antibody and bovine serum albumin as the interferences. Upon successful detection of anti-HBcAg in spiked buffer samples, impedimetric detection of the antibody was then further carried out in spiked human serum samples. The electrochemical response showed a linear relationship between electron transfer resistance and the concentration of anti-HBcAg ranging from 3.91ngmL-1 to 125.00ngmL-1 with lowest limit of detection (LOD) of 3.80ngmL-1 at 3σm-1. This established method exhibits potential as a fast and convenient way to detect anti-HBcAg.

Clinical Characteristics and Correlation Analysis of Subjects with Chronic Hepatitis B Virus (HBV) Infection and Sustained Low Levels of Hepatitis B Surface Antigen (HBsAg).

BACKGROUND The aim of this study was to investigate the clinical characteristics of individuals with chronic hepatitis B virus (HBV) infection with persistent low levels of hepatitis B surface antigen (HBsAg) and to undertake a correlation analysis of the clinical characteristics. MATERIAL AND METHODS The study included 1,204 subjects with chronic HBV infection. Serum HBsAg, HBV envelope antigen (HBeAg), and HBV core antigen (HBcAg) levels were measured using the chemiluminescent microparticle immunoassay (CMIA) and the neutralization test. HBV DNA was measured using real-time fluorescence quantitative polymerase chain reaction (RT-FQ-PCR). RESULTS There were 1,023 subjects in the high-level HBsAg group (HBsAg level ≥10 IU/mL) and 181 subjects in the low-level HBsAg group (HBsAg level <10 IU/mL). In the low-level HBsAg group, the main serological pattern (93.37%) was HBsAg and HBeAg and HBcAg-positive (HBV-M2), and the asymptomatic carrier (ASC) status was 98.34%. The low-level HBsAg group had a lower HBV DNA-positive rate compared with the high-level HBsAg group (40.33% vs. 75.07%), with a normal distribution across all age groups (P>0.05). The low-level HBsAg group included an older age group. A low-level of HBsAg was positively correlated with a low level of replication of HBV DNA (r=0.452). CONCLUSIONS The findings of this study showed that individuals with chronic HBV infection and sustained low-levels of HBsAg were an older population and had a lower level of replicating HBV DNA when compared with individuals with high levels of HBsAg, and the majority (93.7%) were also HBsAg and HBeAg and HBcAg-positive.

Analysis of clinical features and pathology of serum HBsAg positive glomerulonephritis.

To analyze the relationship between the factors related to the occurrence of HBV-GN and serum HBsAg-positive glomerulonephritis. A total of 56 patients were enrolled in the present study. All enrolled cases were divided into two groups according to whether HBsAg and/or HBcAg was present in renal kidney tissue: patients with Hepatitis B virus-associated nephritis (HBV-GN group, 30 cases) and patients with hepatitis B virus-combined nephritis (HBV-CG group, 26 cases). We sought to analyze the differences in clinical features and pathological characteristics in both groups. The rate of HBeAg positivity in the HBV-GN group was considerably increased in the HBV-CG group (P < 0.05), and the number of patients with HBsAg+HBeAg+HBcAb+ in the HBV-GN group was considerably increased in the HBV-CG group (21 cases vs 10 cases) (P < 0.05). Moreover, the number of MCD patients diagnosed by renal biopsy in the HBV-GN group was reduced compared with the HBV-CG group (1 case vs 7 cases) (P < 0.05). HBV infection and high-virus proliferation status were closely related with HBV-GN.

Europium (III) chelate microparticle-based lateral flow immunoassay strips for rapid and quantitative detection of antibody to hepatitis B core antigen.

Quantitative hepatitis B core antigen (anti-HBc) measurements could play an important role in evaluating therapeutic outcomes and optimizing the antiviral therapy of chronic hepatitis B infection. In this study, we have developed a simple and rapid fluorescence point-of-care test based on a lateral flow immunoassay (LFIA) method integrated with Eu (III) chelate microparticles to quantitatively determine anti-HBc concentrations in serum. This assay is based on a direct competitive immunoassay performed on lateral flow test strips with an assay time of 15 min. The Eu (III) chelate microparticle-based LFIA assay could quantitatively detect anti-HBc levels with a limit of detection of 0.31 IU mL-1, and exhibited a wide linear range (0.63-640 IU mL-1). The intra- and inter-assay coefficients of variation for anti-HBc were both less than 10% and a satisfactory dilution test and accuracy were demonstrated. There were no statistically significant differences in sensitivity or specificity in serum samples between the Eu (III) chelate microparticle-based LFIA strips and the Abbott Architect kit. A simple, rapid and effective quantitative detection of anti-HBc was possible using the Eu (III) chelate microparticle-based LFIA strips. The strips will provide diagnostic value for clinical application.

Predictive Value of Hepatitis B Core-Related Antigen (HBcrAg) During the Natural History of Hepatitis B Virus Infection.

BACKGROUND: The natural history of HBV infection includes immune tolerance (IT), immune clearance (IC), HBeAg-negative inactive/quiescent carrier (ENQ), and HBeAg-negative hepatitis (ENH) phases. As the current biomarkers for discriminating the four phases still have some weaknesses, additional serological indicators are needed. Hepatitis B core-related antigen (HBcrAg) encoded with the precore/core gene contains denatured HBeAg, HBV core antigen (HBcAg), and a 22-KDa precore protein (p22cr) and has been demonstrated to have a close association with the natural history of hepatitis B infection. However, no specific cutoff values and diagnostic parameters have been identified to evaluate the diagnostic efficacy. This study aimed to clarify the distribution of HBcrAg levels and evaluate the diagnostic performance during the natural history of HBV infection in a Western Chinese population. METHODS: In this study, 294 samples were collected from treatment-naive HBV infection patients in different phases (IT = 64; IC = 72; ENQ = 100, and ENH = 58). We detected the HBcrAg values and analyzed the relationship between HBcrAg and HBV DNA. HBsAg and other clinical parameters were quantitatively detected. RESULTS: The HBcrAg levels of IT, IC, ENQ, and ENH were 9.30 log U/mL, 8.80 log U/mL, 3.00 log U/mL, and 5.10 log U/mL, respectively (p < 0.0001). Receiver operating characteristic curve analysis demonstrated that the areas under the curves (AUCs) for HBcrAg and quantitative HBsAg at cutoff values of 9.25 log U/mL and 4.355 log IU/mL for distinguishing the IT phase from the IC phase were 0.704 and 0.694, with a sensitivity of 53.13% and 79.69% and specificity of 76.39% and 59.72%, respectively. AUCs of HBcrAg and quantitative HBsAg at cutoff values of 4.15 log U/mL and 2.395 log IU/mL for discriminating between the ENQ and ENH phases were 0.931 and 0.653, with a sensitivity of 87.93% and 91.38% and specificity of 84.00% and 39.00%, respectively. CONCLUSIONS: HBcrAg levels varied significantly among the four natural phases of HBV infection and had higher predictive performance than quantitative HBsAg for distinguishing between ENQ-patients and ENH-patients and a similar performance as HBsAg for the discrimination between IT and IC phases, which indicated that HBcrAg could be a potential serological marker for HBV infection.

Occult Hepatitis B Virus Infection in Hyperlipidemia Patients.

Chronic hepatitis B virus (HBV) infection is associated with lower prevalence of hyperlipidemia (HLP). However, occult HBV infection (OBI) in HLP patients has not yet been explored. OBI is defined as the presence of detectable HBV DNA in serum or liver tissue but undetectable HBV surface antigen in serum. In this study, 1,036 HLP patients and 1,134 replacement blood donor controls were recruited. Among them, 252 HLP patients and 255 blood donors with antibody to HBV core positive were selected and analyzed. HBV DNA was confirmed by nucleic acid testing assays, and nucleotide mutations were analyzed. OBI was detected in 9.5% (24/252) of HLP patients and 2.4% (6/255) of blood donors, respectively (P < 0.001). In HLP population, 41.7% of OBI and 13.6% of non-OBI carriers were associated with daily alcohol consuming > 30 g/day (P < 0.01), while in control population those rates were not statistically different between OBI and non-OBI carriers (P > 0.05). Viral load of OBI in HLP patients was higher than that of OBI in blood donors (P < 0.05), which was a positive correlation between total cholesterol and HBV viral load levels (r = 0.474 P = 0.019). HBV vaccination rate was found significantly lower in OBI HLP patients than that in non-OBI HLP patients (P < 0.01). Importantly, mutations were found in basic core promoter region of HBV among OBI HLP patients. In conclusion, the frequency of OBI is significantly higher in HLP patients, especially those patients with heavy daily alcohol consumption.

Hepatitis B Virus-Encoded MicroRNA Controls Viral Replication.

MicroRNAs (miRNAs) are a class of small, single-stranded, noncoding, functional RNAs. Hepatitis B virus (HBV) is an enveloped DNA virus with virions and subviral forms of particles that lack a core. It was not known whether HBV encodes miRNAs. Here, we identified an HBV-encoded miRNA (called HBV-miR-3) by deep sequencing and Northern blotting. HBV-miR-3 is located at nucleotides (nt) 373 to 393 of the HBV genome and was generated from 3.5-kb, 2.4-kb, and 2.1-kb HBV in a classic miRNA biogenesis (Drosha-Dicer-dependent) manner. HBV-miR-3 was highly expressed in hepatoma cell lines with an integrated HBV genome and HBV+ hepatoma tumors. In patients with HBV infection, HBV-miR-3 was released into the circulation by exosomes and HBV virions, and HBV-miR-3 expression had a positive correlation with HBV titers in the sera of patients in the acute phase of HBV infection. More interestingly, we found that HBV-miR-3 represses HBsAg, HBeAg, and replication of HBV. HBV-miR-3 targets the unique site of the HBV 3.5-kb transcript to specifically reduce HBc protein expression, levels of pregenomic RNA (pgRNA), and HBV replication intermediate (HBV-RI) generation but does not affect the HBV DNA polymerase level, thus suppressing HBV virion production (replication). This may explain the low levels of HBV virion generation with abundant subviral particles lacking core during HBV replication, which may contribute to the development of persistent infection in patients. Taken together, our findings shed light on novel mechanisms by which HBV-encoded miRNA controls the process of self-replication by regulating HBV transcript during infection.IMPORTANCE Hepatitis B is a liver infection caused by the hepatitis B virus (HBV) that can become a long-term, chronic infection and lead to cirrhosis or liver cancer. HBV is a small DNA virus that belongs to the hepadnavirus family, with virions and subviral forms of particles that lack a core. MicroRNA (miRNA), a small (∼22-nt) noncoding RNA, was recently found to be an important regulator of gene expression. We found that HBV encodes miRNA (HBV-miR-3). More importantly, we revealed that HBV-miR-3 targets its transcripts to attenuate HBV replication. This may contribute to explaining how HBV infection leads to mild damage in liver cells and the subsequent establishment/maintenance of persistent infection. Our findings highlight a mechanism by which HBV-encoded miRNA controls the process of self-replication by regulating the virus itself during infection and might provide new biomarkers for diagnosis and treatment of hepatitis B.

Hepatitis B viremia in completely immunized individuals negative for anti-hepatitis B core antibody.

The presence of anti-hepatitis B virus (HBV) core antibody (anti-HBc) is considered a sensitive lifetime marker of HBV infection. Here, we examined this dogma by investigating the prevalence of hepatitis B viremia in anti-HBc negative complete vaccines in Taiwan.A total of 795 participants (1.7-20.0 years old) had completed HBV vaccination in infancy and were anti-HBc negative. Serum samples were available for 460 individuals with isolated anti-HBV surface antibodies (anti-HBs) (HBsAg-negative and anti-HBc negative) and for 245 individuals who tested negative for all 3 markers (triple seronegative). All samples were submitted for polymerase chain reaction (PCR) targeting both the preS/S and X/pre-C gene regions.Of the 460 participants with isolated anti-HBs, 26 (5.65%) were positive for HBV by 2-target PCR. Of the 245 triple seronegative samples, 12 (4.90%) were positive for HBV DNA. In the former group, the prevalence of viremia was significantly higher in individuals aged 6 to 10 years than in all other ages combined (11.82% vs 3.7%, P = 0.001). The anti-HBs titers were significantly lower in participants 6 to 10 years old than in all other ages combined (72.06 vs 99.64 mIU/mL, P = 0.038). In total, 7 (0.99%) subjects had quantifiable HBV DNA levels (280-18,820 IU/mL). Sequence analysis of the S gene revealed vaccine escape like mutations.Hepatitis B viremia can occur in completely vaccinated individuals who are negative for anti-HBc.

Intrahepatic distribution of hepatitis B virus antigens in patients with and without hepatocellular carcinoma.

AIM: To study the intrahepatic expression of hepatitis B surface antigen (HBsAg) and hepatitis B core antigen (HBcAg) in chronic hepatitis B patients with and without hepatocellular carcinoma. METHODS: A total of 33 chronic hepatitis B patients (mean age of 40.3 ± 2.5 years), comprising of 14 HBeAg positive and 19 HBeAg negative patients; and 13 patients with hepatitis B virus related hepatocellular carcinoma (mean age of 49.6 ± 4.7 years), were included in our study. Immunohistochemical staining for HBcAg and HBsAg was done using standard streptavidin-biotin-immunoperoxidase technique on paraffin-embedded liver biopsies. The HBcAg and HBsAg staining distributions and patterns were described according to a modified classification system. RESULTS: Compared to the HBeAg negative patients, the HBeAg positive patients were younger, had higher mean HBV DNA and alanine transaminases levels. All the HBeAg positive patients had intrahepatic HBcAg staining; predominantly with "diffuse" distribution (79%) and "mixed cytoplasmic/nuclear" pattern (79%). In comparison, only 5% of the HBeAg-negative patients had intrahepatic HBcAg staining. However, the intrahepatic HBsAg staining has wider distribution among the HBeAg negative patients, namely; majority of the HBeAg negative cases had "patchy" HBsAg distribution compared to "rare" distribution among the HBeAg positive cases. All but one patient with HCC were HBeAg negative with either undetectable HBV DNA or very low level of viremia. Intrahepatic HBcAg and HBsAg were seen in 13 (100%) and 10 (77%) of the HCC patients respectively. Interestingly, among the 9 HCC patients on anti-viral therapy with suppressed HBV DNA, HBcAg and HBsAg were detected in tumor tissues but not the adjacent liver in 4 (44%) and 1 (11%) patient respectively. CONCLUSION: Isolated intrahepatic HBcAg and HBsAg can be present in tumors of patients with suppressed HBV DNA on antiviral therapy; that may predispose them to cancer development.