Search Results (183)

Hepatitis B virus (HBV) represents a significant global health challenge, affecting over 254 million individuals and contributing to 1.1 million deaths from liver-related complications in 2022. The World Health Organization has set ambitious targets to reduce HBV infections and mortality by 2030. However, only a small proportion (13%) of infected individuals receives timely diagnosis and treatment. HBV elimination efforts necessitate substantial improvements in HBV diagnosis, particularly in identifying early-stage infections, occult HBV infections (OBI), and breakthrough cases. The hepatitis B surface antigen (HBsAg) is a key biomarker in HBV diagnosis, serving as a reliable indicator of infection status and treatment response. Conventional HBsAg assays, with a lower limit of detection (LoD) between 0.03 and 250 IU/mL, often fail to detect OBI and HBV reactivation. In contrast, ultrasensitive HBsAg assays, with an LoD as low as 0.005 IU/mL, can improve the identification of low concentration levels of HBsAg, facilitating earlier diagnosis, monitoring of therapeutic response, and assessment for functional cure. Research confirms the superiority of ultrasensitive assays in detecting HBV in cases missed by conventional assays, detecting NAT-yield samples, and enabling earlier detection of HBV reactivation. This review examines the challenges in HBV diagnostics and the clinical utility of ultrasensitive HBsAg assays in improving progress toward global HBV elimination. Full article

Background/Objectives: Hepatitis B virus (HBV) remains a persistent challenge for transfusion safety. Although testing for hepatitis B surface antigen (HBsAg) and nucleic acid testing (NAT) reduces transmission risk, antibodies to hepatitis B core antigen (anti-HBc) and antibodies to hepatitis B surface antigen (anti-HBs) provide additional insight into past infection and vaccine-induced immunity. We aimed to determine their seroprevalence among blood donors in southern Croatia and assess associations with age, occupation, and time since vaccination. Methods: This cross-sectional study was conducted between February and November 2024 at two regional transfusion centers in southern Croatia. A total of 1008 voluntary blood donors, all HBsAg- and NAT-negative, were tested for anti-HBc and anti-HBs using chemiluminescent microparticle immunoassay. Demographic and vaccination data were collected through verified medical records. Results: Anti-HBc was detected in 0.5% of donors, exclusively among the unvaccinated. Protective anti-HBs levels were found in 38.1% overall and 70.6% of vaccinated donors, with significant declines by age and more than 15 years post-vaccination (p = 0.024). Healthcare workers showed higher seroprotection than non-healthcare donors (67.0% vs. 35.1%; p < 0.001), although one-third still lacked protective levels. Conclusions: HBV exposure was rare, but waning vaccine-induced immunity was evident, with protective anti-HBs levels in 70.6% of vaccinated donors, declining with age and time since vaccination. These findings highlight the need for periodic monitoring of anti-HBs and targeted booster strategies, especially in older and occupationally exposed groups. HBsAg and NAT provide a high level of transfusion safety, while the role of routine anti-HBc testing in this low-endemic context should be carefully evaluated in view of its potential benefits and drawbacks. Donor-based surveillance is a valuable tool for evaluating long-term vaccine effectiveness and guiding public health policy. Full article

Chronic hepatitis B virus (HBV) infection remains a major global health challenge, substantially contributing to liver-related morbidity and mortality. Background/Objectives: Developing therapeutic strategies that overcome immune tolerance and achieve functional cures is an urgent priority. Methods: In this study, we report a therapeutic vaccine comprising hepatitis B surface antigen (HBsAg) formulated with the dual adjuvant system CpG 1018S and QS-21. The immunogenicity and therapeutic efficacy of this vaccine were systematically evaluated in an rAAV8-HBV1.3-established chronic HBV mouse model. Results: The vaccine elicited a robust Th1-skewed immune response, characterized by elevated anti-HBs IgG2b titers and an increased IgG2b/IgG1 ratio. Notably, immunized mice showed markedly reduced circulating HBsAg levels. Mechanistically, the CpG 1018S and QS-21 adjuvant system enhanced dendritic cell activation, maturation, and antigen presentation, expanded HBV-specific CD4⁺ and CD8⁺ T cell populations, and attenuated the expression of the exhaustion markers TIM-3 and TIGIT. Additionally, immunized mice exhibited restored T cell polyfunctionality, with an increased secretion of effector cytokines, including TNF-α and IL-21. These responses collectively contributed to the reversal of T cell exhaustion and breakdown of immune tolerance, facilitating sustained viral suppression. Conclusions: Our findings demonstrate that the CpG 1018S/QS-21-adjuvanted vaccine induces potent humoral and cellular immunity against chronic HBV infection and represents a promising candidate for clinical chronic HBV (CHB) treatment. Full article

The burden of hepatitis delta virus (HDV) infection is currently unknown and may affect 12 to 72 million people distributed across various hot spots in different regions of the globe. Screening for antibodies to HDV infection in patients positive for the hepatitis B surface antigen (HBsAg) is generally available in most parts of the world, but systematic testing for HDV is needed. Chronic HDV infection is associated with a higher risk of progression to cirrhosis, liver failure, and hepatocellular carcinoma compared to hepatitis B virus (HBV) mono-infection. Bulevirtide is the recently available treatment against hepatitis delta. The results of efficacy studies and new drugs (lonafarnib) are under discussion. New therapeutic strategies are in development, revealing a critical need for valid next-generation treatments to cure HDV. Full article

Background/Objectives: Identifying dietary factors influencing liver cancer is crucial for developing preventive measures. While tea polyphenols have demonstrated cancer-preventive activities in animal models, the evidence in humans is not definitive. This study aims to explore the association between tea consumption and liver cancer, as well as the interaction between tea drinking and other risk factors, in China, a country with a high incidence of liver cancer and substantial tea consumption. Methods: A population-based case–control study was conducted in Jiangsu Province from 2003 to 2010. Socio-demographic data, history of tea consumption, and serum markers of hepatitis B virus (HBV) and hepatitis C virus (HCV) infections were evaluated. Unconditional logistic regression was used to examine the associations between tea consumption and the odds of liver cancer. Potential interactions between tea consumption and other major liver cancer risk factors were assessed. Results: A total of 2011 incident liver cancer cases and 7933 controls were included in the analysis. Regular tea drinking showed an inverse association with the risk of liver cancer compared with those who never drank tea (OR: 0.79; 95% CI: 0.63–0.99). Current tea drinking showed an inverse association with liver cancer (OR: 0.51; 95% CI: 0.39–0.66), while former tea drinking showed a positive association (OR: 3.56; 95% CI: 2.42–5.23). Current tea consumption was inversely associated with liver cancer incidence among both hepatitis B surface antigen (HBsAg) positive (OR: 0.45; 95% CI: 0.28–0.73) and HBsAg negative participants (OR: 0.51, 95% CI: 0.36–0.73), among both never and ever tobacco smokers, ever alcohol drinkers (OR: 0.46; 95% CI: 0.33–0.63), and among those without family history of liver cancer. Multiplicative and additive interactions were observed between tea drinking and HBsAg, alcohol consumption, and history of raw water drinking. Conclusions: Tea consumption is inversely associated with the development of primary liver cancer, with potential interactions involving HBV infection, alcohol consumption, and raw (unsafe) water drinking. Increasing tea consumption—particularly among high-risk populations such as individuals who consume alcohol—may serve as an additional preventive measure for liver cancer. This should be considered alongside established strategies, including HBV vaccination, alcohol cessation, and avoidance of drinking raw water, to help reduce liver cancer risk. Full article

Chronic infection with the hepatitis B virus (HBV) results in over 1 million deaths annually. Although currently licensed treatments, including pegylated interferon-α and nucleoside/nucleotide analogs, can inhibit viral replication, they rarely eradicate covalently closed circular DNA (cccDNA) reservoirs. Moreover, vaccination does not offer therapeutic benefit to already infected individuals or non-responders. Consequently, chronic infection is maintained by the persistence of cccDNA in infected hepatocytes. For this reason, novel therapeutic strategies that permanently inactivate cccDNA are a priority. Obligate heterodimeric transcription activator-like effector nucleases (TALENs) provide the precise gene-editing needed to disable cccDNA. To develop this strategy using a therapeutically relevant approach, TALEN-encoding mRNA targeting viral core and surface genes was synthesized using in vitro transcription with co-transcriptional capping. TALENs reduced hepatitis B surface antigen (HBsAg) by 80% in a liver-derived mammalian cell culture model of infection. In a stringent HBV transgenic murine model, a single dose of hepatotropic lipid nanoparticle-encapsulated TALEN mRNA lowered HBsAg by 63% and reduced viral particle equivalents by more than 99%, without evidence of toxicity. A surveyor assay demonstrated mean in vivo HBV DNA mutation rates of approximately 16% and 15% for Core and Surface TALENs, respectively. This study presents the first evidence of the therapeutic potential of TALEN-encoding mRNA to inactivate HBV replication permanently. Full article

Hepatitis B is a serious infectious disease that threatens the health of all mankind. In this study, we isolated and extracted hydroxytyrosol from Lindernia ruellioides with anti-hepatitis B virus (HBV) activity. The structure of hydroxytyrosol was identified by the nuclear magnetic resonance technique. HepG2.2.15 cell models were used to detect the anti-HBV activity and liver protection of hydroxytyrosol in vitro. Hydroxytyrosol can inhibit hepatitis B surface antigen (HBsAg) and hepatitis B e-antigen (HBeAg). The IC₅₀ values of HBsAg and HBeAg were 4.02 mg/L and 5.19 mg/L, respectively. At the highest concentration of hydroxytyrosol, the inhibition rates of supernatant and intracellular HBV DNA were 75.99% and 66.33%, respectively. Hydroxytyrosol was less toxic to normal human hepatocytes. Molecular docking showed that hydroxytyrosol was bound to three amino acid residues of HBV polymerase with a binding energy of −7.0 kcal/mol. This study provided data for the development and utilization of Lindernia ruellioides and the research and development of anti-hepatitis B virus drugs. Full article

Background: Hepatitis B virus (HBV) is a major cause of morbidity and mortality globally, and chronic infections are associated with cirrhosis and hepatocellular carcinoma. Issues with conventional treatments and vaccines mean there is a need for new therapeutic vaccines, which must elicit a strong and sustainable immune response. Here, we evaluated the immunogenicity of dual-antigen vaccines containing hybrid surface (hy-LHBs) and core (HBc) antigens, combined with a carboxyl-vinyl polymer (CVP) as a mucoadhesive excipient, following intranasal administration in mice. Methods: Mice were intranasally administered a mixed vaccine (10 µg of hy-LHBs and 2.5 or 10 µg of HBc) with or without a CVP excipient, and they were assessed for their immune response (levels of IgGs or IgA antibodies in an ELISA, IFN-γ level in splenocytes in an ELISpot assay, and cytokine/chemokine levels in a BioPlex assay). A protein stability assay was also conducted for vaccine formulations with and without excipients. Results: Significantly enhanced IgG production was noted targeting hy-LHBs and (less markedly) HBc at 10 µg/antigen, but only a non-significant elevation was noted with the vaccine containing 2.5 µg HBc. The BioPlex assay showed a significant increase in IL-2 (#00-07, 0B), IL-12(p40)(#00), eotaxin (#00), MIP1α (#00, #00-07, 0B), and MCP-1 (#00-07, 0B) in mice that received treatment compared to those of untreated mice. The endpoint titers of IgG1 and IgG2a were measured, which were higher with CVP excipients than without. From the IgG2a/IgG1 ratio, a higher IgG1 response was induced by CVPs to hy-LHBs and a higher IgG2a response was induced to HBc. Th2-dominant phenotype to hy-LHBs was induced with CVP#00 in an ELISpot assay. The highest anti-hy-LHBs antibody titer was noted with the conventional CVP#00 excipient. Consistent with these results, a higher amount of neutralizing antibodies of HBV was induced with CVP#00 treatment and followed by #00-03 and #14-00. Conclusions: We consider that the addition of CVP excipients to vaccine formulation enhances immunogenicity and HBV antigen stability for intranasal vaccines. This effect was seen for both humoral and cell-mediated immune responses, indicating the potential of CVPs as excipients in intranasal HBV vaccines. Full article

Chronic hepatitis B is linked with considerable liver-related morbidity and mortality globally. Human leukocyte antigen (HLA) polymorphisms affect the susceptibility and outcome of many immune-mediated diseases and infections. Our aim was to study the impact of HLA alleles on HVB-infected individuals in a Greek population. In total, 107 patients with chronic HBV infection (cHBV group) and 101 with spontaneous clearance (SC-group) of hepatitis B surface antigen (HBsAg) were genotyped for HLA-A, HLA-B, HLA-C, HLA-DRB1, and HLA-DQB1 loci by single-specific primer polymerase chain reaction (PCR-SSP). The HLA alleles’ frequencies were compared between the two patient groups and healthy individuals from the North Greece Bone Marrow Donor Registry (14506 samples). We found a significantly increased frequency of HLA-C*01 and HLA-DRB1*16 alleles in the cHBV group versus the SC-group. The frequency of HLA-A*01, HLA-B*08, HLA-C*01, HLA-C*08, HLA-DRB1*03, and HLA-DQB1*05 alleles was significantly higher in cHBV patients versus healthy individuals, while the frequency of the HLA-B*38 allele was significantly lower. Our study showed an association of specific HLA alleles with either susceptibility or protection against chronic HBV infection. Full article

Hepatitis B virus (HBV) is an important global public health issue. The World Health Organization (WHO) 2024 Global Hepatitis Report estimated that the global prevalence of people living with HBV infection is 254 million, with an estimated prevalence incidence of 1.2 million new HBV infections yearly. Previous studies have shown that natural compounds have antiviral inhibition potentials. In silico methods such as molecular docking, virtual screening, pharmacophore modeling, quantitative structure–activity relationship (QSAR), and molecular dynamic simulations have been successfully applied in identifying bioactive compounds with strong binding energies in HBV treatment targets. The COVID-19 pandemic necessitated the importance of repurposing already approved drugs using in silico methods. This study is aimed at unveiling the benefits of in silico techniques as a potential alternative in natural compounds’ drug discovery and repurposing for HBV therapy. Relevant articles from PubMed, Google Scholar, and Web of Science were retrieved and analyzed. Furthermore, this study comprehensively reviewed the literature containing identified bioactive compounds with strong inhibition of essential HBV proteins. Notably, hesperidin, quercetin, kaempferol, myricetin, and flavonoids have shown strong binding energies for hepatitis B surface antigen (HBsAg). The investigation reveals that in silico drug discovery methods offer an understanding of the mechanisms of action, reveal previously overlooked viral targets (including PreS1 Domain of HBsAg and cccDNA (Covalently Closed Circular DNA) regulators, and facilitate the creation of specific inhibitors. The integration of in silico, in vitro, and in vivo techniques is essential for the discovery of new drugs for HBV therapy. The insights further highlight the importance of natural compounds and in silico methods as targets in drug discovery for HBV therapy. Moreover, the combination of natural compounds, an in silico approach, and drug repurposing improves the chances of personalized and precision medicine in HBV treatment. Therefore, we recommend drug repurposing strategies that combine in vitro, in vivo, and in silico approaches to facilitate the discovery of effective HBV drugs. Full article

Background/Objectives: In chronic hepatitis B infection (CHB), the hepatitis B surface antigen (HBsAg) continuously exhausts the hepatitis B surface antibody (HBsAb), which leads to the formation of immune tolerance. Accordingly, the hepatitis B virus (HBV) infection can be blocked by inhibiting the binding of the hepatitis B surface pre-S1/pre-S2 antigen to the hepatocyte receptor NTCP, but the clinical cure rate of pre-S-based vaccines for CHB is limited. Methods: In this study, we designed and prepared multivalent hepatitis B therapeutic mRNA vaccines encoding three hepatitis B surface antigen proteins (L, M, and S) at the cell membrane, verified via in vitro transfection and expression experiments. An in vivo immunization experiment in HBV transgenic (Tg) mice was first completed. Subsequently, an adeno-associated virus plasmid vector carrying the HBV1.2-fold genome (pAAV HBV1.2) model and the adeno-associated virus vector carrying HBV1.3-fold genome (rAAV HBV1.3) model were constructed and immunized with mRNA vaccines. The HBV antigen, antibodies, and HBV DNA in serum were detected. Indirect (enzyme-linked immunosorbent assay) ELISA were made to analyze the activated antigen-specific IgG in HBV Tg mice. Antigen-dependent T-cell activation experiments were carried out, as well as the acute toxicity tests in mice. Results: The L protein/pre-S antigens could be stably presented at the cell membrane with the support of the S protein (and M protein). After vaccinations, the vaccines effectively reactivated the production of high levels of HBsAb, disrupted immune tolerance, and activated the production of high-affinity antibodies against structural pre-S antigen in HBV Tg mice. The HBsAg seroconversion and serum HBV DNA clearance were achieved in two HBV mice models. Furthermore, pre-S antigen-dependent T-cell response against HBV infection was confirmed. The therapeutic vaccine also showed safety in mice. Conclusions: A novel therapeutic mRNA vaccine was developed to break through HBsAg-mediated immune tolerance and treat CHB by stably presenting the pre-S antigen at the membrane, and the vaccine has great potential for the functional cure of CHB. Full article

Background: Hepatitis B (HBV) and Delta (HDV) virus infections pose critical public health challenges, particularly in Romania, where HDV co-infection is underdiagnosed. Methods: This study investigates the epidemiology, risk factors, and clinical outcomes of HBV/HDV co-infection in vulnerable populations, leveraging data from the LIVE(RO2) program. Conducted between July 2021 and November 2023, the program screened 320,000 individuals across 24 counties, targeting socially disadvantaged groups such as rural residents, the Roma community, and those lacking health insurance. Results: Among 6813 hepatitis B surface antigen (HBsAg)-positive individuals, HDV antibody prevalence was 4.87%, with active replication confirmed in 75.6% of HDV-positive cases. Regional disparities emerged, with higher HDV prevalence and replication rates in the Eastern region compared to the South. HDV-positive individuals were more likely to be younger, male, and from rural or socioeconomically disadvantaged backgrounds. Clinically, HDV co-infection correlated with increased liver stiffness, advanced fibrosis stages, and lower steatosis levels compared to HBV mono-infection. Psychiatric comorbidities were more prevalent among HDV-positive patients, highlighting the need for integrated care. Conclusions: This study underscores the urgent need for targeted public health interventions, including enhanced screening, education, and access to novel antiviral therapies like bulevirtide to address the significant burden of HBV/HDV co-infection in Romania. Full article

Since the discovery of the Australia antigen, now known as the hepatitis B surface antigen (HBsAg), significant research has been conducted to elucidate its physical, chemical, structural, and functional properties. Subviral particles (SVPs) containing HBsAg are highly immunogenic, non-infectious entities that have not only revolutionized vaccine development but also provided critical insights into HBV immune evasion and viral assembly. Recent advances in cryo-electron microscopy (cryo-EM) have uncovered the heterogeneity and dynamic nature of spherical HBV SVPs, emphasizing the essential role of lipid–protein interactions in maintaining particle stability. In this review, recent progress in understanding the molecular architecture of HBV SVPs is consolidated, focusing on their symmetry, lipid organization, and disassembly–reassembly dynamics. High-resolution structural models reveal unique lipid arrangements that stabilize hydrophobic residues, preserve antigenicity, and contribute to SVP functionality. These findings highlight the significance of hydrophobic interactions and lipid–protein dynamics in HBV SVP assembly and stability, offering valuable perspectives for optimizing SVP-based vaccine platforms and therapeutic strategies. Full article

Due to the lack of agents that directly target covalently closed circular DNA and integrated HBV DNA in hepatocytes, achieving a complete cure for chronic hepatitis B (CHB) remains challenging. The latest guidelines recommend (hepatitis B surface antigen) HBsAg loss as the ideal treatment target for improving liver function, histopathology, and long-term prognosis. However, even after HBsAg loss, hepatitis B virus can persist, with a risk of recurrence, reactivation, cirrhosis, and hepatocellular carcinoma. Therefore, follow-up and surveillance are still necessary. With increasing treatment options available for achieving HBsAg loss in patients with CHB, developing effective surveillance strategies has become crucial. Recent studies on outcomes following HBsAg loss provide new insights for refining current surveillance strategies, though further improvement is needed through long-term observation and follow-up. Full article

Background: Pediatric hepatitis B virus (HBV) serostatus remains variably characterized, hardly determined at times, or documented as part of national monitoring of the Extended Programs for Immunization (EPI). Methods: We cross-sectionally characterized the seroprevalence of HBV vaccine and/or infection status among 501 and 288 children <5 and 15–17 years old, respectively, in Kawempe Division, Kampala, Uganda, between May and August 2023. These children received HBV vaccination under the Uganda National Extended Program on Immunizations (UNEPI). Samples were qualitatively screened for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (HBsAb or anti-HBs), hepatitis B e antigen (HBeAg), hepatitis B e antibody (HBeAb or anti-HBe), and for hepatitis B core antibody (HBcAb or anti-HBc) using three different HBV Combo test rapid immunochromatographic diagnostic tests: Nova, Fastep, and Beright. Results: The seroprevalence of HBsAg, anti-HBs, HBeAg, anti-HBe, and anti-HBc was 1.52%, 27.75%, 0.88%, 0.63%, and 0.76%, respectively, for the combined study age groups. The HBsAg seroprevalence of 2.78% was almost 3.5-fold higher among adolescents when compared to the 0.8% observed in the under-5-year-olds. The qualitative seroprevalence of anti-HBs was 33.1% and 18.4% in the under-5 and among the 15–17-year-old study groups, respectively. Conclusions: The proportion of qualitatively detectable anti-HBs in both groups of vaccinated children is low and probably indicates reduced seroprotection. Consequently, a large proportion of children who received the hepatitis B vaccine under UNEPI may be at risk of HBV infection, especially adolescents. A booster dose of the Hepatitis B Vaccine may be required for adolescents. Full article