Latent viral infections rely on a precise coordination of the immune response to control sporadic viral reactivation. CD8+ T cells play a crucial role in controlling viral latency by generating diverse memory responses in an epitope-specific manner. Among these distinct responses, conventional and inflationary memory responses have been described during herpesvirus infections. Using a newly generated TCR transgenic mouse strain, we investigated the transcriptomic and epigenetic remodeling of distinct epitope-specific CD8+ T cells during CMV infection across tissues at both population and single-cell levels. Our findings reveal that whereas the transcriptomic and epigenetic landscapes of conventional and inflationary memory responses diverge in the spleen and liver, these molecular programs converge in the salivary gland, a site of CMV persistence. Thus, we provide evidence that the dynamics of memory CD8+ T cell responses are distinct between tissues.

The Hepatitis B Virus has long afflicted the human race, with a widespread impact on the global health system and profound medical implications for those who are chronically infected. Despite its relatively recent discovery, over the last 50 years great advancements have been made towards the characterisation of this complex etiological agent. The virus itself has a highly evolved genome which encodes for seven viral proteins, three of which (the surface antigens) were consequential in the initial discovery and isolation of the virus. These surface antigens are ubiquitously important throughout the viral lifecycle, from capsid envelopment through to receptor-mediated invasion into the hepatocytes. The hepatitis B surface antigens (in particular, the large protein) adopt complex topological folds and tertiary structures, and it is this topological intricacy which facilitates the diverse roles the three surface antigens play in HBV maturation and infection. Here, the biochemical and topological attributes of the three surface antigens are reviewed in detail, with particular focus on their relevance to the establishment of infection. Further research is still required to elucidate the coordinates of the antigen loop and the dynamic topological changes of key motifs during entry and viral morphogenesis; these in turn may provide new leads for therapeutics which may potentiate a functional cure for chronic hepatitis B.

To provide accurate diagnostic evidence for early hepatitis B virus (HBV) infection-related diseases, this study targeted HBV DNA as an analyte, where a sandwich-type electrochemical DNA sensor based on gold nanoparticles/reduced graphene oxide (Au NPs/ERGO) and cerium oxide/gold-platinum nanoparticles (CeO2/AuPt NPs) was constructed. Au NPs/ERGO composite nanomaterials were first synthesized on the surface of a glass carbon electrode using electrochemical co-reduction, which significantly improved the specific surface area and electrical conductivity of the electrode. Further specific hybridization of target HBV-DNA was performed by combining capture probe DNA (S1-DNA) bound to AuNPs/ERGO with CeO2/AuPt modified signal probe DNA (S2-DNA). Leveraging the excellent H2O2 catalytic activity of the CeO2/AuPt nanocomposite, the constructed sandwich-type electrochemical DNA sensor was used to detect HBV DNA. By optimizing the detection conditions, the sensor showed a good linear response in the range of 1 fmol/L to 1 nmol/L, with a detection limit as low as 0.36 fmol/L. The sensor had good specificity, repeatability, and stability. Further, spiked recovery experiments of actual serum samples showed recoveries ranging from 98.7 % to 102.7 %, and the relative standard deviations were all lower than 4.77 %. This study provides a new method for the detection of HBV DNA with potential clinical applications.

To identify clinical and viral indicators for the development of a new model to accurately differentiate the stages of chronic hepatitis B virus (HBV) infection based on histopathological changes in the liver.

Clinical and liver pathology data from chronic hepatitis B (CHB) patients who underwent liver biopsy were retrospectively collected. The patients were allocated into test and validation groups. The area under the receiver operating characteristic (ROC) curve (AUC) was calculated to idneitfy the optimal diagnostic value for differentiating the stages of chronic HBV infection.

A total of 118 patients and 73 patients who met the diagnostic and inclusion criteria were selected as the test group and validation group, respectively. Multivariate analysis revealed that HBeAg was independently correlated with the IT and IC stages. The cutoff value of HBeAg used to quantitatively differentiate between IT and IC was 1335 S/CO. The AUC values were 0.921 (95% confidence interval (CI): 0.836-0.971) and 0.846 (95% CI: 0.726-0.967) in the test and validation groups, respectively. A new prediction model of the IT stage was established by using three indicators, namely, HBeAg, HBsAg and HBV DNA. The AUC values were 0.923 (95% CI: 0.864-0.982, p < 0.001) and 0.89 (95% CI: 0.787-0.994, p < 0.01) in the test and validation groups, respectively, when this prediction model was used. For the new model, CMA guidelines (2019 version), EASL guidelines (2017 version) and AASLD guidelines (2018 version), the error rates in the test group were 4.65%, 11.62%, 23.26%, and 46.51%, respectively, while the errors rates in the validation group were 20.0%, 25.0%, 40.0%, and 45.0%, respectively.

High levels of HBeAg, rather than HBeAg positivity, may serve as a predictor of the IT stage. A predictive model for the immune tolerance stage was established by combining three indicators. Compared with the recommended standards from multiple current guidelines, the new prediction model has a significantly lower error rate.

Hepatitis B virus (HBV) exclusively infects hepatocytes and produces large amounts of subviral particles containing its surface antigen (HBsAg). T cell immunity is crucial for controlling and clearing HBV infection. However, the intercellular processes underlying HBsAg presentation to T cells are incompletely understood. Here, using preclinical mouse models, we show that, following HBsAg expression, the intrahepatic Batf3+XCR1+CCR7- conventional dendritic cell subset cDC1 presents HBsAg by MHC-I cross-dressing, driving CD8+ T cell response. Meanwhile, upon HBsAg access to lymphoid tissues, B cells acquire HBsAg directly in the follicles of lymphoid tissues and initiate CD4+ T cell responses sequentially in the follicular and interfollicular regions, guided by chemoattractant receptors CCR5 and EBI2, respectively. Finally, we identify ALCAM, LFA-1, and CD80 as key co-stimulatory signals essential for optimal T cell responses. Thus, these findings reveal the roadmap of non-canonical antigen presentation that drives T cell immunity against HBsAg, advancing novel therapeutic strategies for chronic HBV infection.

Hepatitis B virus (HBV) infection remains a significant global health challenge, characterized by chronic liver inflammation and compromised antiviral immunity. The outcome of HBV infection and associated liver pathogenesis is influenced mainly by the host innate immune and inflammatory responses. Characterizing the mechanisms underlying these responses might provide new therapeutic strategies for HBV treatment. HECT domain and RCC1-like domain 2 (HERC2) belongs to the large HERC family of ubiquitin E3 ligases, which are implicated in tissue development and inflammation. We initially observed that hepatic tissues from chronic hepatitis B patients express lower levels of HERC2 compared with healthy donors. In this study, we identified HERC2 as a critical suppressor of HBV infection. Hepatocyte-specific HERC2-deficient mice exhibited increased susceptibility to HBV infection. Our findings demonstrate that HERC2 directly interacts with TBK1, a vital regulator of the innate immune response, mediating its K33 ubiquitination and activation. This HERC2-mediated activation of TBK1 triggers a signaling cascade that culminates in the activation of transcription factors IRF3 and IRF7, subsequently driving the production of type I interferons, crucial antiviral cytokines. The findings deepen our understanding of the molecular mechanisms underlying HBV pathogenesis and present potential avenues for developing targeted immunomodulatory therapies to combat HBV infection more effectively.

Hepatitis B virus (HBV) infection is a major global health issue. The underdiagnosis of HBV contributes to the increasing mortality from hepatitis B-related complications. Hepatitis B surface antigen is a biomarker guiding the clinical management of chronic hepatitis B, and its disappearance from the blood is a key sign of functional cure. There is a need for highly sensitive detection methods for early intervention and prevention of disease recurrence. We presented a new CRISPR-assisted nanopore sensing method for ultrasensitive detection of hepatitis B surface antigen. It uses the high specificity and turnover efficiency of the CRISPR-Cas12a system. The system is activated by the competitive binding between hepatitis B surface antigen and its aptamer, followed by restriction enzyme digestion. The products are detected by a nanopore for precise quantification at very low concentrations. The result achieves the limit of quantification (LOQ) of 10 fM, outperforming conventional assays. Clinical validation with patient samples confirms its superiority. This integrated technology is a powerful tool for HBV early diagnosis, treatment monitoring, and disease assessment, and paves the way for nanopore technology in clinical diagnostics.

Extracellular high mobility group box 1 (HMGB1) serves as a damage-associated molecular pattern (DAMP) and leads to diverse biological effects, including the aggravation of HBV-related liver diseases. However, mechanisms underlying HMGB1 secretion in HBV-induced hepatic injury and fibrosis remain unclear. Glutamine-rich 1 (QRICH1) is known as a critical effector of endoplasmic reticulum (ER) stress and is elevated in liver diseases. Whether QRICH1 participates in HBV-induced hepatic fibrosis warrants further investigation. Here, we explore the mechanism of HMGB1 secretion during HBV-induced hepatic fibrosis and the effect of QRICH1 on the process.

In vivo experiments were conducted using a chronic recombinant cccDNA (rcccDNA) mouse model. Clinical specimens were obtained from Zhongshan Hospital, Fudan University. The levels of QRICH1 and HMGB1 were determined via immunohistochemistry. Liver collagen deposition was determined by Sirius red and Masson's trichrome staining. The serum levels of HMGB1 and indicators of liver injury were detected via ELISA. HMGB1 cyto-translocation was analyzed by Western blotting and quantitative real-time PCR (qRT-PCR).

Our findings demonstrated that ER stress promoted HBV-induced hepatic fibrosis in a mouse model. QRICH1 expression and HMGB1 secretion were elevated and positively correlated in rcccDNA mice with ER stress activation and chronic hepatitis B (CHB) patients with severe fibrosis. HBV modulated Sirtuin6 (SIRT6) expression, affecting HMGB1 cyto-translocation via acetylation regulation. Furthermore, QRICH1 enhanced HBV-induced HMGB1 translocation and secretion by regulating HMGB1 transcription.

HBV promotes HMGB1 acetylation and cyto-translocation by modulating SIRT6 expression. QRICH1 enhances HBV-induced HMGB1 translocation and secretion by regulating HMGB1 transcription.

In 2018, a surprising finding was reported; cats are naturally infected with a virus related to hepatitis B virus (HBV), domestic cat hepadnavirus (DCH). HBV causes chronic hepatitis and hepatocellular carcinoma in people, and HBV-like viruses cause similar diseases in rodents. If DCH negatively impacts feline health then demand for diagnostics, therapeutics, and vaccination will follow. Hence, understanding pathogenic potential of DCH for cats, and the size of any associated disease burden are critical goals. Here we evaluate progress made towards these goals by reviewing published studies of DCH against the backdrop of our understanding of HBV and HBV-like viruses.

Interferons (IFNs) are indispensable innate antiviral cytokines that orchestrate the vertebrate immune response against viral incursions. Nearly every cell possesses the remarkable ability to release IFNs upon detecting viral threats, triggering a robust signaling cascade that alerts neighboring cells and halts viral propagation via paracrine communication. The intricate influence of IFNs is mediated by an extensive network of proteins activated through the Jak-STAT pathways, facilitating the swift transcription of over 300 interferon-stimulated genes (ISGs) that fortify cellular defenses against replication. However, the cunning nature of viruses has led to the evolution of sophisticated evasion strategies, notably through the manipulation of host microRNAs (miRNAs) that disrupt vital components of the IFN signaling machinery. This review delves into the intricate interplay between viral infections and both host- and viral-derived miRNAs, exploring their potent roles in modulating RIG-I-like receptors, Toll-like receptors, IFN receptors, and the JAK/STAT pathway, ultimately shaping the landscape of antiviral immunity.

Hepatitis B e antigen (HBeAg) seroconversion is a crucial event in the natural history of chronic hepatitis B virus (HBV) infection, marked by a significant decrease in viral load and the emergence of mutations that suppress HBeAg expression. However, these mutations alone do not fully account for the reduction in viral load. This study investigated the biological features and pathogenic roles of mutations outside the basal core promoter (BCP) and precore regions during the HBeAg-negative stage of chronic infection. Full-length HBV genomes from HBeAg-positive (n = 180) and HBeAg-negative (n = 328) genotype D datasets were analyzed, revealing significantly higher genomic heterogeneity in HBeAg-negative sequences compared with HBeAg-positive genomes (50.4 ± 16.0 vs. 26.6 ± 10.5 nucleotide changes per genome). Twenty-six hotspot amino acid mutations associated with the HBeAg-negative stage were identified, with over half located in the Core region. Subsequently, full-length HBV genomes from six HBeAg-negative patient-derived serum samples were obtained by PCR amplification followed by Sanger sequencing. Infectious clones generated from these genomes, each carrying between 21 and 66 amino acid substitutions, were characterized, showing that mutations in this stage differentially affected viral fitness in vitro by up- or downregulating HBV-DNA levels (ranging from 0.2 to 5 times those of the wild-type isolate), modulating capsid assembly, and altering the expression, secretion, and subcellular localization of viral proteins. In conclusion, while mutations in the BCP and precore regions are the primary drivers of HBeAg seroconversion, mutations outside these regions significantly influence HBV biology and potentially contribute to viral pathogenicity, underscoring the complex interplay between host and virus during the HBeAg-negative stage of chronic infection.

Cellular immune responses are crucial in determining outcomes of the hepatitis B virus (HBV) infection. Ineffective immune responses enable persistent HBV infection and contribute to progressive liver disease. Understanding the mechanisms underlying immunological HBV tolerance and restoring functional adaptive immune responses is essential for successful chronic hepatitis B (CHB) treatment. This study examined the dysregulated immune responses and immunopathological cell states associated with CHB using single-cell RNA sequencing of peripheral blood mononuclear cells to investigate immune cell composition and transcriptional differences between patients with CHB and healthy donors. Phenotypic alterations in the lymphoid and myeloid compartments were observed following HBV infection. T cell immune profiling in patients with CHB showed enrichment of exhausted CD8+ T cells, impaired cytotoxicity of effector CD8+ T cells, and increased regulatory T cell (Treg) suppressive activity. Immature neutrophils and a unique CD14+ monocyte subset (myeloid-derived suppressor cells) exhibited potent immunosuppressive abilities. A novel population of CD14+CD163+VSIG4+ M2-like macrophages with immunosuppressive and anti-inflammatory phenotypes was enriched in a patient with severe CHB and liver failure, indicating a potential contribution to dysfunctional immune responses. Our study demonstrated immune exhaustion and evasion in chronic HBV infection, elucidating its immunopathological features and suggesting new therapeutic strategies for immune-mediated disorders and unresolved chronic HBV infection.

Chronic hepatitis B virus (HBV) infection affects approximately 254 million individuals globally, contributing to significant morbidity and mortality due to HBV-related liver failure and cirrhosis, which result in millions of fatalities each year. Although approved antiviral nucleos(t)ide analogues can effectively suppress HBV replication, their ability to reduce hepatitis B surface antigen (HBsAg) levels in plasma remains limited. The clinical application of the immunomodulator interferon-alpha is restricted by concerns regarding its safety and the severity of associated adverse reactions, rendering long-term administration challenging. Therefore, current drug development efforts for chronic hepatitis B aim to achieve a functional cure, which is defined as HBsAg serological clearance and sustained suppression of HBV DNA. This review discusses recent advancements in novel direct-acting therapeutic strategies for the treatment of chronic hepatitis B by focusing on the progresses in HBV entry inhibitors, monoclonal antibodies, RNA interferences, and other agents that directly target the virus. Furthermore, we discuss the development of immunomodulatory therapies, including TLR-7/8 agonists, immune checkpoint inhibitors, and therapeutic vaccines. In the end, we conclude by highlighting the importance of the rational combination-strategy design to improve the functional cure rate of HBV.

Aims/Background Hepatitis B virus (HBV) infection poses a challenge to global healthcare. Peginterferon alfa-2b (PEG-IFNα-2b) is an effective treatment for HBV infection. This study aimed to explore the efficacy of PEG-IFNα-2b combined with entecavir in the treatment of HBV infection, its effect on liver function and immune factors, and the risk factors affecting the prognosis of patients with HBV infection. Methods The clinical data of 184 patients with HBV infection who were treated at Jinhua Central Hospital from January 2021 to January 2024 were collected for retrospective analysis. Patients were divided into a control group (not receiving antiviral treatment, n = 34), a standard treatment group (receiving entecavir, n = 85), and a combination treatment group (PEG-IFNα-2b and entecavir, n = 65) according to the treatment approach. Treatment efficacy, liver function indicators (albumin [ALB], alanine aminotransferase [ALT], and aspartate aminotransferase [AST]), immune factor indexes (tumour necrosis factor alpha [TNF-α] and interferon gamma [IFN-γ]), hepatitis B surface antigen [HBsAg] and HBV DNA levels were compared among the three groups. All patients were followed up after treatment. According to their prognosis, the patients were divided into good prognosis group (n = 118) and poor prognosis group (n = 66). Logistic regression analysis was performed to explore the risk factors affecting the prognosis of HBV patients. Results The efficacy in the combination treatment group was higher (92.31%) than that in the control group (8.82%) and the standard treatment group (78.82%) (p < 0.05). After treatment, the HBsAg and HBV DNA levels were decreased in the standard treatment and combination treatment groups (p < 0.05). Compared with the control and standard treatment groups, the combination treatment group exhibited significantly lower HBsAg and HBV DNA levels after treatment (p < 0.05). Besides, the combination treatment group had lower ALT and AST levels (p < 0.05), and higher ALB level (p < 0.05), than the control and standard treatment groups after treatment. Compared with the control and standard treatment groups, the combination treatment group demonstrated decreased TNF-α level and higher IFN-γ level after treatment (p < 0.05). Multivariate logistic regression analysis identified family medical history as the risk factor affecting the prognosis of patients with HBV infection (p = 0.001, odds ratio [OR] = 3.614, 95% confidence interval [CI]: 1.685-7.750) and therapy regimen as the protective factor (p = 0.029, OR = 0.135, 95% CI: 0.022-0.815). Conclusion The PEG-IFNα-2b combination therapy in patients with HBV infection significantly improves the clinical treatment efficacy, liver function, and immune factors. In addition, this study found that therapy regimen and family medical history are independent factors affecting the prognosis of HBV infection.

Hepatitis B infection can lead to liver fibrosis and hepatocellular carcinoma (HCC). Despite antiviral therapies, some patients still develop HCC. This study investigates hepatitis B virus (HBV)-induced hepatocyte-hepatic stellate cell (HSC) crosstalk and its role in liver fibrosis and HCC. Using MYC-driven liver cancer stem cell organoids, HCC-patient-derived xenograft (PDX) models, and HBV replication models, this study reveals that HBV transcription affected hepatocyte development, activated the DNA repair pathway, and promoted glycolysis. HBV activated nicotinamide phosphoribosyltransferase (NAMPT) through DNA damage receptor ATR. NAMPT-insulin receptor (INSR)-mediated hepatocyte-HSC crosstalk caused HSCs to develop a myofibroblast phenotype and activated telomere maintenance mechanisms via PARP1 multisite lactylation. Inhibition of the ATR-NAMPT-INSR-PARP1 pathway effectively blocks HBV-induced liver fibrosis and HCC progression. Targeting this pathway could be a promising strategy for chronic HBV infection management.

Barber-related infections, including hepatitis B virus (HBV), continue to be a major cause of illness and death. Numerous beauticians use razors and scissors on multiple customers without adequately sanitizing these tools. There is a lack of published research on the prevention practices and associated factors of hepatitis B virus infection among barbers in Ethiopia. Therefore, this study aimed to assess the practice and associated factors of hepatitis B virus infection among barbers.

A cross-sectional study was carried out involving 411 barbers selected through simple random sampling. Data collection was performed using an interviewer-administered questionnaire and an observational checklist. The collected data were first cleaned and entered into EpiData version 4.6 and then exported to SPSS version 25 for analysis. Model fitness was assessed using the Hosmer-Lemeshow test, and multicollinearity was evaluated with the variance inflation factor. A binary logistic regression model was employed for the analysis. To address confounding factors, explanatory variables with a p-value of less than 0.25 in the bivariable logistic regression were included in the multivariable logistic regression analysis. Factors with a p-value of less than 0.05 in the multivariable analysis were considered statistically significant.

Among the 411 participants, 328 (79.8, 95% CI: 75.6-83.6%) exhibited unsafe hepatitis B virus infection prevention practices. Unsafe practices were significantly associated with barbers who could not read or write (AOR 3.75, 95% CI: 1.39-10.12); primary and secondary education (AOR 3.44, 95% CI: 1.89-6.27) compared to those with college education and above; not using ultraviolet sterilizers (AOR 2.85, 95% CI: 1.30-6.27); insufficient knowledge (AOR 4.23, 95% CI: 2.13-8.40); unfavorable attitudes toward infection control (AOR 2.40, 95% CI: 1.34-4.31); and working hours of less than 8 h (AOR 0.27, 95% CI: 0.15-0.50).

Nearly four-fifths of barbers exhibited unsafe practices in preventing hepatitis B virus infection. Low education levels, not utilizing UV sterilizers, lack of knowledge, working fewer hours, and negative attitudes toward infection prevention were all strongly associated with unsafe practices in the prevention of hepatitis B virus among barbers. Consequently, these findings underscore the need for targeted educational programs, improved access to sterilization tools, and policy changes to promote safer practices.

Disease diagnosis is not only related to individual health but is also a crucial part of public health prevention. Electrochemical biosensors combine the high sensitivity of electrochemical methods with the inherent high selectivity of biological components, offering advantages such as excellent sensitivity, fast response time, and low cost. The generated electrical signals have a linear relationship with the target analyte, allowing for identification and concentration detection. This has become a very attractive technology. This review offers a summary of recent advancements in electrochemical biosensor research for disease diagnosis in China. It systematically categorizes and summarizes biosensors developed in China for detecting cancer, infectious diseases, inflammation, and neurodegenerative disorders. Additionally, the review delves into the fundamental working principles, classifications, materials, preparation techniques, and other critical aspects of electrochemical biosensors. Finally, it addresses the key challenges impeding the advancement of electrochemical biosensors in China and examines promising future directions for their development.

Chronic HBV infection disproportionately affects people living with HIV, who are often excluded from functional cure studies. This study investigates CD8+ T cell profiles in HBV mono-infection versus HBV/HIV co-infection, examining the impact of long-term therapy on virus-specific responses with the goal of informing therapeutic strategies for immune restoration.

We analysed CD8+ T cell responses in 61 participants (HBV n=20, HBV/HIV n=20, HIV n=21), on suppressive antiviral therapy. We assessed transcriptomic and proteomic profiles, focusing on exhaustion markers alongside virus-specific functional capabilities.

Transcriptomic analysis revealed a distinct signature in co-infection, with upregulation of genes associated with TCR signaling, inhibitory pathways and progenitor-exhausted markers (XCL2, TCF7, PDCD1, IL7R). This gene profile scored highly for a precursor exhausted (Tpex) CD8+ T cell signature, reflecting a "stemness" programme that maintains plasticity despite chronic antigen exposure. Proteomic analysis confirmed higher frequencies of precursor exhausted TCF-1+CD127+PD-1+ CD8+ T cells in co-infection, while HBV mono-infection showed predominance of terminally exhausted ToxhighTCF-1-CD127- cells. These differences correlated with more robust, polyfunctional HBV-specific responses in co-infection against surface and core antigens. Lower HBsAg levels and longer treatment duration in co-infection associated positively with Tpex populations and functional responses and inversely with terminal exhaustion.

Our findings demonstrate that individuals with well-controlled HBV/HIV co-infection maintain more robust CD8+ T cell responses with preserved stem-like properties supporting ongoing antiviral function. These results underscore the benefits of early antiretroviral intervention and the need for tailored immune-modulatory therapies to restore antiviral functionality in these diverse patient populations.

Chronic hepatitis B (CHB) remains a major global health challenge, with functional cure achieved in only a small subset of patients. Current oral antiviral agents effectively suppress viral replication but fail to eliminate the hepatitis B virus (HBV). Recent advances in immunomodulatory therapies offer new hope for improving functional cure rates.

This special report discusses the latest therapeutic strategies targeting immune responses in CHB. We list the mechanisms of immune evasion in HBV infection and highlight emerging immunomodulatory agents. Key findings from recent clinical trials and critical considerations are summarized to provide an overview of ongoing efforts and future direction to achieve functional cure.

While combination therapies hold promise, their real-world feasibility depends on patient selection, combination regimens, costs, and global accessibility. A successful HBV cure strategy must integrate scientific innovation with public health policies to ensure equitable access to effective treatments. Future research should identify key immune mechanisms, optimize combination regimens, and improve global treatment infrastructure.

The purpose of this review is to describe the immune function of the liver, guiding the reader from the homeostatic tolerogenic status to the aberrant activation demonstrated in chronic liver disease. An extensive description of the pathways behind the inflammatory modulation of the healthy liver will be provided focusing on the complex immune cell network residing within the liver. The limit of tolerance will be presented in the context of organ transplantation, seizing the limits of homeostatic mechanisms that fail in accepting the graft, progressing eventually toward rejection. The triggers and mechanisms behind chronic activation in metabolic liver conditions and viral hepatitis will be discussed. The last part of the review will be dedicated to one of the greatest paradoxes for a tolerogenic organ, developing autoimmunity. Through the description of the three most common autoimmune liver diseases, the autoimmune reaction against hepatocytes and biliary epithelial cells will be dissected.

This study investigates the relationship between Cyclin D1 (CCND1) gene and promoter methylation and liver fibrosis (LF)/liver cirrhosis (LC)induced by chronic hepatitis B (CHB). Peripheral blood mononuclear cells (PBMCs) are collected from patients diagnosed with chronic hepatitis B (CHB) and hepatitis B-related LF/LC, as well as from healthy individuals. The mRNA levels and promoter methylation of the CCND1 gene are measured. Single-cell analysis is performed to determine the cell types primarily expressing the CCND1 gene in LF/LC. The GSE84044 dataset is utilized to validate the experimental results. Single-gene GSEA and immune infiltration analyses are conducted to identify significant pathways and immune characteristics associated with the CCND1 gene. The mRNA level of CCND1 in PBMCs from patients with hepatitis B-related LF/LC is elevated compared to those with chronic hepatitis B (CHB) and healthy individuals, while the promoter methylation level of CCND1 is reduced. Single-cell analysis indicates high expression of CCND1 in M2 macrophages (M2) and T cells. The GSE84044 dataset confirms higher CCND1 mRNA levels in liver tissues from patients with CHB-related LF/LC compared to CHB patients. Single-gene GSEA analysis associates CCND1 expression with natural killer cell-mediated cytotoxicity, T cell receptor signaling, and B cell receptor signaling pathways. Increased expression of CCND1 enhances immune infiltration during the fibrosis/cirrhosis process of CHB. The CCND1 expression and promoter methylation may be involved in the process of LF/LC in CHB and may be related to the immune response in the course of the disease.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related mortality worldwide, with chronic infections by hepatotropic viruses such as hepatitis B virus (HBV), and hepatitis C virus (HCV), being major risk factors. Chronic infections with these viruses are the leading cause of HCC worldwide, with HBV alone responsible for over 50% of cases. Despite advances in direct-acting antivirals (DAAs) for HCV and nucleos(t)ide analogues (NAs) for HBV, challenges remain in HCC prevention, early detection, and treatment. Recent research highlights the role of viral-induced metabolic alterations, such as the Warburg effect, mitochondrial dysfunction, and lipid dysregulation, in promoting HCC. Moreover, immune checkpoint inhibitors have emerged as effective treatments for advanced HCC, though responses vary between HBV- and HCV-related cancers. Additionally, novel therapeutic approaches and metabolic-targeted therapies offer promising avenues for virus-associated HCC treatment. Advancements in liquid biopsy biomarkers and artificial intelligence-driven diagnostics are improving HCC surveillance and risk stratification, potentially enabling earlier interventions. While HBV vaccination has significantly reduced HCC incidence, disparities in global vaccination coverage persist. Furthermore, antiviral therapies combined with structured surveillance programs have proven effective in reducing HCC incidence and mortality. This review highlights the complex connection between viral, genetic, and environmental factors in HCC development and underscores the importance of integrated prevention strategies to reduce its burden globally.

Toxocariasis is a zoonotic parasitic disease that is widely prevalent in the world. Toxocara canis adults are parasitic in the small intestinal tract of canids, and the larvae migrate to the liver and lungs before reaching the final destination. Our previous experiments have confirmed that T. canis infection could affect the composition of host intestinal microbial flora. In this experiment, we further analyze the potential effects of T. canis infection on host liver and lung microbial flora. Utilizing 16s rRNA high-throughput sequencing, coupled with various bioinformatics analysis techniques, our study revealed that T. canis infection significantly elevated the abundance of certain opportunistic pathogens in the host's liver and lungs. This marked elevation contributes to the establishment of infection. Through cluster analysis, we found that the changes in the microbiota of the liver and lungs were independent of the microbial flora carried by T. canis adults. However, whether the changes are due to the migration of larvae remains to be explored. In short, T. canis infections have a significant impact on the abundance and diversity of flora in the host tissues, and the changes in microbiota abundance and diversity could further influence tissue homeostasis and immune responses, thus regulating the establishment of infection.

In this study, we have identified two novel peptides, 19Ac (comprising residues 91-105) and 20Ac (encompassing residues 96-110), from a systematically designed peptide library based on the Hepatitis B virus (HBV) core protein, that inhibit the assembly of HBV capsid. Peptide 20Ac exhibited about twofold the inhibitory potency of 19Ac and proved effective against both standard and morphothiadin (GLS4)-resistant HBV strains. Molecular dynamics simulations revealed that despite their overlapping sequence, 19Ac and 20Ac bonded to different regions of the core protein, thereby inhibiting capsid assembly through distinct mechanisms. These peptides could serve as valuable seed compounds for the further development of HBV capsid inhibitors, including GLS4-resistant strains.

Dendritic cells and the exosomes they secrete play a crucial role in the immune system, and studies have shown that dendritic cell function is dramatically reduced in patients with chronic hepatitis B. Alcohol could stimulate dendritic cell maturation. Consequently, the present work explored the therapeutic effect of alcohol-induced dendritic cells and their exosomes in hepatitis B virus (HBV) infection. We systematically investigated the functional effects of alcohol stimulation and HBV infection on dendritic cells and their exosomes, as well as cocultured alcohol-induced dendritic cells and exosomes with lymphocytes from HBV transgenic mice and chronic hepatitis B patients to study the T cell immune response. Our findings revealed that alcohol significantly accelerated the maturation of bone marrow-derived dendritic cells in mice and dendritic cells in patients with chronic hepatitis B, but had no effect on the DC2.4 cell line. Simultaneously, HBV infection was demonstrated to inhibit dendritic cell activation and maturation, as well as exosomes. More importantly, alcohol-induced dendritic cells enhanced T-cell immunity in HBV transgenic mice and chronic hepatitis B patients, and their exosomes had the same impact. The maturation of dendritic cells and their exosomes can be effectively induced by alcohol. Meanwhile, alcohol-induced maturation of dendritic cells and exosomes can significantly repair the poor T-cell immunity caused by HBV infection, making it a promising novel treatment for chronic hepatitis B patients in the future.

Chronic Hepatitis B (CHB) is a leading cause of liver fibrosis and cirrhosis worldwide. The early detection of liver fibrosis remains challenging due to the lack of specific symptoms and noninvasive biomarkers with high sensitivity. The polymeric immunoglobulin receptor (PIGR) has recently emerged as a potential biomarker for liver fibrosis. This study aims to evaluate the utility of PIGR in CHB patients as a biomarker for liver fibrosis.

This retrospective study analyzed 150 CHB patients from 2018 to 2023. Based on liver biopsy results, 34 patients were classified as having liver fibrosis, while 116 were categorized as non-fibrosis. Clinical data were compared to assess the relationship between PIGR expression levels and serum fibrosis indices. Logistic regression was performed to identify factors influencing liver fibrosis, and the predictive value of PIGR was evaluated using a receiver operating characteristic (ROC) curve.

Significant differences were observed in collagen type IV (CIV), procollagen type III N-terminal peptide (PCIIINP), and hyaluronic acid (HA) levels between the fibrosis and non-fibrosis groups (P < 0.05). PIGR levels were significantly higher in the fibrosis group (P < 0.05) and positively correlated with HA, laminin (LN), PCIII, and CIV levels (P < 0.05). Logistic regression identified HA, LN, PCIIINP, and CIV as risk factors, with PIGR being an independent predictor (P < 0.05). At a cutoff value of 0.35, PIGR showed an area under the curve (AUC) of 0.839, with 81.90% sensitivity, 79.41% specificity, and a Youden's index of 0.613. PIGR also provided a higher net benefit than APRI.

PIGR levels are significantly elevated in CHB-related liver fibrosis and correlate closely with established fibrosis markers. As an independent predictor, PIGR demonstrates high diagnostic accuracy and holds promise as a non-invasive biomarker for detecting liver fibrosis in CHB patients, with significant potential for clinical application.

The development of therapeutic drugs and vaccines requires the availability of appropriate model animals that replicate the pathogenesis of human diseases. Both native and transgenic animals can be utilized as models. The advantage of transgenic animals lies in their ability to simulate specific properties desired by researchers. However, there is often a need for the rapid production of transgenic animal models, especially in situations like a pandemic, as was evident during COVID-19. An important tool for transgenesis is the adeno-associated virus. The genome of adeno-associated virus serves as a convenient expression cassette for delivering various DNA constructs into cells, and this method has proven effective in practice. This review analyzes the features of the adeno-associated virus genome that make it an advantageous vector for transgenesis. Additionally, examples of utilizing adeno-associated viral vectors to create animal models for hereditary, oncological, and viral human diseases are provided.

To interrogate the role of specific immune cells in infection, cancer, and autoimmunity, immunologists commonly use monoclonal depletion antibodies (depletion-mAbs) or genetically engineered mouse models (GEMMs). To generate a tool that combines specific advantages and avoids select drawbacks of the two methods, we engineered adeno-associated viral vectors expressing depletion mAbs (depletion-AAVs). Single-dose depletion-AAV administration durably eliminated lymphocyte subsets in mice and avoided accessory deficiencies of GEMMs, such as marginal zone defects in B cell-deficient animals. Depletion-AAVs can be used in animals of different genetic backgrounds, and multiple depletion-AAVs can readily be combined. Exploiting depletion-AAV technology, we showed that B cells were required for unimpaired CD4+ and CD8+ T cell responses to chronic lymphocytic choriomeningitis virus (LCMV) infection. Upon B cell depletion, CD8+ T cells failed to suppress viremia, and they only helped resolve chronic infection when antibodies dampened viral loads. Our study positions depletion-AAVs as a versatile tool for immunological research.

Hepatitis B is one of the killer communicable diseases, with a global estimation of 1.1 million deaths resulting from liver diseases annually. The search for HBV therapeutics has resulted in repurposing the existing antiretrovirals (ARVs) for HBV treatment, considering their shared common replication mechanisms. This review is aimed at evaluating the potencies of some of the repurposed ARVs used for HBV treatment, analyzing the common mechanisms of viral replications in HBV and HIV, and investigating the potentials of traditional medicines as an alternative treatment for HBV patients. The topical keywords drug repurposing, drug repositioning, antiretrovirals, hepatitis B treatment, HBV, natural products, traditional medicines, title, and abstract were searched in PubMed, Web of Science, and Google Scholar. The advanced search included the five years, 2019-2024. The search result was filtered from 377 to 110 relevant articles. The evaluation reveals that CD4+ T cells are targeted by HIV, while HBV targets the liver with its associated diseases (cirrhosis and hepatocellular carcinoma (HCC)). Furthermore, treatments with the available repurposed ARVs only prevent or slow down the progression to cirrhosis, reduce the HCC incidence, and can improve the quality of life and increase life expectancy; however, they are not curative for HBV. Traditional medicines/natural product extracts or their phytochemicals exert anti-HBV effects through different mechanisms. Traditional medicines exert improved therapeutic effects when combined properly. The investigation further reveals that consideration of an in silico approach in HBV therapeutics might not only streamline drug development but also contribute to a deeper understanding of viral pathogenesis. Therefore, we recommend the integration of computational drug design methods with traditional medicine and natural product screening for discovering new bioactive HBV drug candidates.

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.

Hepatocyte nuclear factor 6 (HNF6), a member of the HNF family, contains single cleft and homologous domains, which form a DNA-binding region that targets the promoter regions of genes that bind to liver-specific genes and regulate their expression. Furthermore, HNF6 is highly expressed as an HNF in the liver.

HNF6 regulates not only the formation of the liver but also the proliferation and differentiation of hepatocytes. Additionally, HNF6 controls the migration and adhesion of hepatocellular carcinoma cells and plays a significant role in liver metabolism. Its expression is affected by epigenetic modifications such as DNA methylation, post-translational modifications, and microRNAs. Recently, HNF6 was also found to be expressed in tissues, such as the pancreas, intestine, and lungs, where it controls their formation by regulating cell differentiation and influences their pathophysiological processes via various mechanisms.

In this review, we highlight advances in HNF6-related research concerning liver diseases and provide a summary of its potential mechanisms of action as a transcription factor in regulating downstream genes and epigenetic modifications. We also highlight gaps in liver disease research and provide future research directions for the application of HNF6 and its downstream molecules as attractive targets in the treatment of liver diseases.

As a highly complex organ with digestive, endocrine, and immune-regulatory functions, the liver is pivotal in maintaining physiological homeostasis through its roles in metabolism, detoxification, and immune response. Various factors including viruses, alcohol, metabolites, toxins, and other pathogenic agents can compromise liver function, leading to acute or chronic injury that may progress to end-stage liver diseases. While sharing common features, liver diseases exhibit distinct pathophysiological, clinical, and therapeutic profiles. Currently, liver diseases contribute to approximately 2 million deaths globally each year, imposing significant economic and social burdens worldwide. However, there is no cure for many kinds of liver diseases, partly due to a lack of thorough understanding of the development of these liver diseases. Therefore, this review provides a comprehensive examination of the epidemiology and characteristics of liver diseases, covering a spectrum from acute and chronic conditions to end-stage manifestations. We also highlight the multifaceted mechanisms underlying the initiation and progression of liver diseases, spanning molecular and cellular levels to organ networks. Additionally, this review offers updates on innovative diagnostic techniques, current treatments, and potential therapeutic targets presently under clinical evaluation. Recent advances in understanding the pathogenesis of liver diseases hold critical implications and translational value for the development of novel therapeutic strategies.

Hepatitis B virus surface antigen (HBsAg), IgM and IgG antibodies to hepatitis B virus core antigen (anti-HBcIgM and anti-HBcIgG) comprise serological markers of hepatitis B virus (HBV) infection of great importance in the epidemiological surveillance of hepatitis B, since they have been routinely considered for classifying the acute and chronic clinical forms of HBV infection. This classification is established according to the expression and dynamics of these markers in the infected person's bloodstream, which serves as the basis for the differential diagnosis between the two clinical entities. However, in certain circumstances, both acute and chronic infection, the detection of these markers may not occur in the bloodstream, favoring the occurrence of atypical serological profiles of infection, and compromising the correct infection clinical classification. In addition, the complex and varied nature of hepatitis B serological profiles may compromise the health professional's ability to analyze the case and, thus, correctly classify the infection's clinical form. Since the expression of these markers in the bloodstream occurs dynamically, with consequent changes in the patient's serological profile as he progresses towards recovery or chronicity, the diagnosis of acute or chronic infection may also be compromised, if it is established based on the collection of a single sample and without knowing the patient's clinical history and their epidemiological antecedents. This manuscript addresses the sensitivity and specificity of HBsAg, anti-HBcIgM, and anti-HBcIgG serological markers detection in the clinical classification of HBV infection and in the epidemiological surveillance of hepatitis B. This review is covering the clinical and epidemiological interpretations of the markers in and of themselves, not in reference to any specific assays.

Chronic hepatitis B (CHB) poses a major global public health challenge and is a leading cause of cirrhosis and liver cancer. Hepatic steatosis is common in individuals with CHB compared to the non-CHB population and is particularly prevalent in hepatitis B virus (HBV)-endemic regions, affecting about one-third of CHB patients. The interaction between hepatic steatosis and CHB-related disease progression is complex and still under debate. Evidence demonstrates that co-existing steatosis may worsen liver fibrosis while paradoxically increasing the likelihood of achieving better HBV control. In particular, despite the association of steatotic liver disease (SLD) with lower HBV viral loads and higher rates of HBsAg seroclearance, the coexistence of CHB and SLD can potentially accelerate liver disease progression. Factors such as fat deposition, lipotoxicity, oxidative stress, and chronic inflammation in SLD may foster a pro-fibrotic and pro-carcinogenic environment, accelerating the disease progression. Additionally, loss of global DNA methylation, changes in the immune microenvironment, and genetic susceptibility further contribute to the development of CHB-related cirrhosis and hepatocellular carcinoma (HCC). This review examines the mechanisms driving liver disease progression and the heightened risk of cirrhosis and HCC in patients with concurrent CHB and steatotic liver disease, underscoring the importance of prioritizing antiviral therapy for CHB in addition to addressing SLD.

Hepatitis B virus (HBV) infection is a global health concern. The current sequential endpoints for the treatment of HBV infection include viral suppression, hepatitis B e antigen (HBeAg) seroconversion, functional cure, and covalently closed circular DNA (cccDNA) clearance. Serum hepatitis B core-related antigen (HBcrAg) is an emerging HBV marker comprising three components: HBeAg, hepatitis B core antigen, and p22cr. It responds well to the transcriptional activity of cccDNA in the patient's liver and is a promising alternative marker for serological testing. There is a strong correlation, and a decrease in its level corresponds to sustained viral suppression. In patients with chronic hepatitis B (CHB), serum HBcrAg levels are good predictors of HBeAg seroconversion (both spontaneous and after antiviral therapy), particularly in HBeAg-positive patients. Both low baseline HBcrAg levels and decreasing levels early in antiviral therapy favored HBsAg seroconversion, which may serve as a good surrogate option for treatment endpoints. In this review, we summarize the role of serum HBcrAg in the treatment of CHB. Therefore, long-term continuous monitoring of serum HBcrAg levels contributes to the clinical management of patients with CHB and optimizes the choice of treatment regimen, making it a promising marker for monitoring HBV cure.

Current antiviral therapy for the chronic hepatitis B virus (HBV) has a low clinical cure rate, high administration frequency, and limited efficacy in reducing HBsAg levels, leading to poor patient compliance. Novel agents are required to achieve HBV functional cure, and reduction of HBV antigenemia may enhance the activation of effective and long-lasting host immune control. HT-101 is a siRNA currently in phase I clinical trials with promising prospects for future applications. By designing and synthesizing siRNA targeting the conserved HBV S region, we evaluated its inhibitory effect on HBV biomarkers across four different genotypes (A-D). Additionally, potential cytotoxic effects were investigated. The in vivo effects and duration of inhibition were assessed using a HBV/adeno-associated virus mouse model. The EC50 values for HBV DNA, HBsAg, HBeAg, and HBV RNA in the supernatant of HepG2.2.15 cells were determined to be 0.3348 0.1696, 4.329, and 2.831 nM, respectively, while the CC50 of HT-101 against the viability of Hep2, H1 HeLa, MRC-5, HEK293, and Huh7 cell lines all exceeded 1 μM significantly. Compared with the vehicle group from days 7 to 70 postdosing, especially in the high-dose group (9 mpk), plasma levels of HBsAg, HBeAg, and HBV DNA were significantly reduced with mean reduction values ranging from 1.72 to 3.38 log10 copy/mL due to long-lasting suppression of HBsAg below the lower limit of quantitation (LLOQ), ultimately leading to induction of anti-HBs. In summary, the preclinical data demonstrate that HT-101 represents a significant breakthrough in reducing antigens and provides a promising strategy for functional cure of HBV.

Coexistence of hepatitis B surface antigen (HBsAg) and hepatitis B surface antibody (anti-HBs) has been observed in some chronic hepatitis B (CHB) patients (DP patients), but the clinical outcomes and comprehensive characterization of immune micro-environmental changes for this specific population remain inconclusive. In this study, we retrospectively analyze the prognosis of 305 patients in Foshan City, Guangdong Province, China, and also investigated the molecular immunology changes in HBsAg and anti-HBs double positive CHB patients (DP group), CHB patients who had recovered from IFN-ɑ treatment (RP group), and healthy controls (HC group) using T cell receptor (TCR) and B cell receptor (BCR) immune repertoire sequencing. Our findings revealed that 22.30% of DP patients were diagnosed with severe liver disease. Immune repertoire sequencing revealed significant skewing in the diversities of T cell receptor β-chain (TRB) and immunoglobulin heavy chain (IGH) in the DP group compared to the RP group. Unique V(D)J gene combinations, such as IGHV1-18/IGHD3-22/IGHJ5, IGHV1-8/IGHD6-13/IGHJ3, and IGHV1-8/IGHD6-19/IGHJ3, as well as TRBV12-3/TRBD1/TRBJ1-5 and TRBV11-2/TRBD2/TRBJ2-1, exhibited distinct utilization patterns in the DP group. Moreover, the top ten most utilized amino acid motifs in the complementarity determining region 3 (CDR3) of TRB in the DP group showed significant differences from those in the RP group. Notably, motifs such as "xxxYDSSGYx" and "AREx" in the IGH CDR3s were selectively prevalent in the DP group. These findings are expected to provide evidence supporting the poor clinical prognosis of DP patients and offer new insights into the distinct immune micro-environmental changes of this group.

The natural stages of chronic hepatitis B can be divided into four stages according to changes in virology, biochemistry, and pathology. However, there have been significant differences in the recommended stage criteria in the several major guidelines for chronic hepatitis B, especially regarding the immune tolerance phase. Inconsistent standards of indicators for different stages resulted in some problems, such as incorrect stage, uncertain stages and poor comparation of related studies. We propose suggestions for revisions to the stage criteria for CHB based on recent researches, including three stages: immune tolerance stage, immune clearance stage, and immune control stage. These revision suggestions rationalize some of the existing problems with the stage criteria for CHB and can significantly reduce the number of patients in the "uncertain stage" or "gray zone," which is particularly valuable in guiding clinical practice. However, further clinical studies with large samples are needed to confirm these suggestions.

This study aims to construct and validate noninvasive diagnosis models for evaluating significant liver fibrosis in patients with chronic hepatitis B (CHB). A cohort of 259 CHB patients were selected as research subjects. Through random grouping, 182 cases were included in the training set and 77 cases in the validation set. The nomogram was developed based on univariate analysis and multivariate regression analysis. Various machine learning models were employed to construct prediction models for significant liver fibrosis. The area under the ROC curve (AUC), sensitivity, specificity, NPV, PPV, and F1 score were used to evaluate the diagnostic performance. The new nomogram had excellent diagnostic efficiency (AUC 0.806, 95% CI: 0.740-0.872). Compared with other traditional noninvasive diagnostic models, the nomogram demonstrated higher AUC values and better prediction performance. Among six machine learning models, the random forest (RF) model achieved the highest AUC (AUC 0.819, 95% CI: 0.720-0.906). Finally, the importance of all variables in the RF model was ordered to illustrate the contribution of different variables, providing the clinical factors associated with the risk of significant liver fibrosis. This new nomogram may more reliably than other traditional models and the RF model demonstrated superior accuracy among six machine learning models.