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Viruses May 2024Hepatitis B and C viruses (HBV and HCV) are the leading causes of end-stage liver disease worldwide. Although there is a potent vaccine against HBV, many new infections... (Review)
Review
Hepatitis B and C viruses (HBV and HCV) are the leading causes of end-stage liver disease worldwide. Although there is a potent vaccine against HBV, many new infections are recorded annually, especially in poorly resourced places which have lax vaccination policies. Again, as HBV has no cure and chronic infection is lifelong, vaccines cannot help those already infected. Studies to thoroughly understand the HBV biology and pathogenesis are limited, leaving much yet to be understood about the genomic features and their role in establishing and maintaining infection. The current knowledge of the impact on disease progression and response to treatment, especially in hyperendemic regions, is inadequate. This calls for in-depth studies on viral biology, mainly for the purposes of coming up with better management strategies for infected people and more effective preventative measures for others. This information could also point us in the direction of a cure. Here, we discuss the progress made in understanding the genomic basis of viral activities leading to the complex interplay of the virus and the host, which determines the outcome of HBV infection as well as the impact of coinfections.
Topics: Humans; Hepatitis B virus; Hepatitis B; Coinfection; Genome, Viral; Animals
PubMed: 38793606
DOI: 10.3390/v16050724 -
Viruses Apr 2024Chronic Hepatitis B and D Virus (HBV and HDV) co-infection is responsible for the most severe form of viral Hepatitis, the Hepatitis Delta. Despite an efficient vaccine... (Review)
Review
Chronic Hepatitis B and D Virus (HBV and HDV) co-infection is responsible for the most severe form of viral Hepatitis, the Hepatitis Delta. Despite an efficient vaccine against HBV, the HBV/HDV infection remains a global health burden. Notably, no efficient curative treatment exists against any of these viruses. While physiologically distinct, HBV and HDV life cycles are closely linked. HDV is a deficient virus that relies on HBV to fulfil is viral cycle. As a result, the cellular response to HDV also influences HBV replication. In vitro studying of HBV and HDV infection and co-infection rely on various cell culture models that differ greatly in terms of biological relevance and amenability to classical virology experiments. Here, we review the various cell culture models available to scientists to decipher HBV and HDV virology and host-pathogen interactions. We discuss their relevance and how they may help address the remaining questions, with one objective in mind: the development of new therapeutic approaches allowing viral clearance in patients.
Topics: Humans; Hepatitis Delta Virus; Hepatitis B virus; Hepatitis D; Virus Replication; Animals; Host-Pathogen Interactions; Coinfection; Cell Culture Techniques; Hepatitis B
PubMed: 38793598
DOI: 10.3390/v16050716 -
Viruses Apr 2024The concurrent seropositivity of HBsAg and anti-HBs has been described among patients with chronic hepatitis B (CHB), but its prevalence is variable. HBV S-gene...
The concurrent seropositivity of HBsAg and anti-HBs has been described among patients with chronic hepatitis B (CHB), but its prevalence is variable. HBV S-gene mutations can affect the antigenicity of HBsAg. Patients with mutations in the 'α' determinant region of the S gene can develop severe HBV reactivation under immunosuppression. In this study at a tertiary liver center in the United States, we evaluated the frequency and virological characteristics of the HBsAg mutations among CHB patients with the presence of both HBsAg and anti-HBs. In this cohort, 45 (2.1%) of 2178 patients were identified to have a coexistence of HBsAg and anti-HBs, and 24 had available sera for the genome analysis of the Pre-S1, Pre-S2, and S regions. The frequency of mutations in the S gene was significantly higher among those older than 50 years (mean 8.5 vs. 5.4 mutations per subject, = 0.03). Twelve patients (50%) had mutations in the 'α' determinant region of the S gene. Mutations at amino acid position 126 were most common in eight subjects. Three had a mutation at position 133. Only one patient had a mutation at position 145-the classic vaccine-escape mutation. Despite the universal HBV vaccination program, the vaccine-escape mutant is rare in our cohort of predominantly Asian patients.
Topics: Humans; Hepatitis B Surface Antigens; Female; Male; Middle Aged; Hepatitis B virus; Mutation; Adult; Hepatitis B Antibodies; Hepatitis B, Chronic; Tertiary Care Centers; United States; Immune Evasion; Aged; Prevalence; Young Adult
PubMed: 38793596
DOI: 10.3390/v16050713 -
Viruses Apr 2024This systematic review investigates the immunosuppressive environment in HBV-associated hepatocellular carcinoma (HCC), characterized by dysfunctional and exhausted... (Review)
Review
This systematic review investigates the immunosuppressive environment in HBV-associated hepatocellular carcinoma (HCC), characterized by dysfunctional and exhausted HBV-specific T cells alongside an increased infiltration of HBV-specific CD4+ T cells, particularly regulatory T cells (Tregs). Heightened expression of checkpoint inhibitors, notably PD-1, is linked with disease progression and recurrence, indicating its potential as both a prognostic indicator and a target for immunotherapy. Nevertheless, using PD-1 inhibitors has shown limited effectiveness. In a future perspective, understanding the intricate interplay between innate and adaptive immune responses holds promise for pinpointing predictive biomarkers and crafting novel treatment approaches for HBV-associated HCC.
Topics: Carcinoma, Hepatocellular; Humans; Liver Neoplasms; Hepatitis B virus; Adaptive Immunity; T-Lymphocytes, Regulatory; Programmed Cell Death 1 Receptor; Immune Checkpoint Inhibitors; Hepatitis B; Hepatitis B, Chronic; CD4-Positive T-Lymphocytes; T-Lymphocytes; Immunotherapy
PubMed: 38793588
DOI: 10.3390/v16050707 -
International Journal of Molecular... May 2024Our aim was to develop an accurate, highly sensitive method for HBV genotype determination and detection of genotype mixtures. We examined the preS and 5' end of the HBV...
Our aim was to develop an accurate, highly sensitive method for HBV genotype determination and detection of genotype mixtures. We examined the preS and 5' end of the HBV X gene (5X) regions of the HBV genome using next-generation sequencing (NGS). The 1852 haplotypes obtained were subjected to genotyping via the Distance-Based discrimination method (DB Rule) using two sets of 95 reference sequences of genotypes A-H. In clinical samples from 125 patients, the main genotypes were A, D, F and H in Caucasian, B and C in Asian and A and E in Sub-Saharan patients. Genotype mixtures were identified in 28 (22.40%) cases, and potential intergenotypic recombination was observed in 29 (23.20%) cases. Furthermore, we evaluated sequence conservation among haplotypes classified into genotypes A, C, D, and E by computing the information content. The preS haplotypes exhibited limited shared conserved regions, whereas the 5X haplotypes revealed two groups of conserved regions across the genotypes assessed. In conclusion, we developed an NGS-based HBV genotyping method utilizing the DB Rule for genotype classification. We identified two regions conserved across different genotypes at 5X, offering promising targets for RNA interference-based antiviral therapies.
Topics: Hepatitis B virus; Humans; High-Throughput Nucleotide Sequencing; Genotype; Haplotypes; Hepatitis B; Genotyping Techniques; Conserved Sequence; Coinfection; Genome, Viral; Male; Female; Phylogeny; DNA, Viral; Adult
PubMed: 38791519
DOI: 10.3390/ijms25105481 -
Biochemistry Jun 2024Hepatitis B virus (HBV) displays remarkable self-assembly capabilities that interest the scientific community and biotechnological industries as HBV is leading to an...
Hepatitis B virus (HBV) displays remarkable self-assembly capabilities that interest the scientific community and biotechnological industries as HBV is leading to an annual mortality of up to 1 million people worldwide (especially in Africa and Southeast Asia). When the ionic strength is increased, hepatitis B virus-like particles (VLPs) can assemble from dimers of the first 149 residues of the HBV capsid protein core assembly domain (Cp149). Using solution small-angle X-ray scattering, we investigated the disassembly of the VLPs by titrating guanidine hydrochloride (GuHCl). Measurements were performed with and without 1 M NaCl, added either before or after titrating GuHCl. Fitting the scattering curves to a linear combination of atomic models of Cp149 dimer (the subunit) and = 3 and = 4 icosahedral capsids revealed the mass fraction of the dimer in each structure in all the titration points. Based on the mass fractions, the variation in the dimer-dimer association standard free energy was calculated as a function of added GuHCl, showing a linear relation between the interaction strength and GuHCl concentration. Using the data, we estimated the energy barriers for assembly and disassembly and the critical nucleus size for all of the assembly reactions. Extrapolating the standard free energy to [GuHCl] = 0 showed an evident hysteresis in the assembly process, manifested by differences in the dimer-dimer association standard free energy obtained for the disassembly reactions compared with the equivalent assembly reactions. Similar hysteresis was observed in the energy barriers for assembly and disassembly and the critical nucleus size. The results suggest that above 1.5 M, GuHCl disassembled the capsids by attaching to the protein and adding steric repulsion, thereby weakening the hydrophobic attraction.
Topics: Guanidine; Hepatitis B virus; Capsid; Capsid Proteins; Scattering, Small Angle; Protein Multimerization; Models, Molecular; Virus Assembly; X-Ray Diffraction
PubMed: 38787909
DOI: 10.1021/acs.biochem.4c00077 -
Journal of Virology Jun 2024The antiviral role of the tripartite motif-containing (TRIM) protein family , a member of the E3-ubiquitin ligase family, has recently been actively studied. Hepatitis B...
The antiviral role of the tripartite motif-containing (TRIM) protein family , a member of the E3-ubiquitin ligase family, has recently been actively studied. Hepatitis B virus (HBV) infection is a major contributor to liver diseases; however, the host factors regulated by cytokine-inducible TRIM21 to suppress HBV remain unclear. In this study, we showed the antiviral efficacy of TRIM21 against HBV in hepatoma cell lines, primary human hepatocytes isolated from patient liver tissues, and mouse model. Using TRIM21 knock-out cells, we confirmed that the antiviral effects of interferon-gamma, which suppress HBV replication, are diminished when TRIM21 is deficient. Northern blot analysis confirmed a reduction of HBV RNA levels by TRIM21. Using Luciferase reporter assay, we also discovered that TRIM21 decreases the activity of HBV enhancers, which play a crucial role in covalently closed circular DNA transcription. The participation of the RING domain and PRY-SPRY domain in the anti-HBV effect of TRIM21 was demonstrated through experiments using deletion mutants. We identified a novel interaction between TRIM21 and hepatocyte nuclear factor 4α (HNF4α) through co-immunoprecipitation assay. More specifically, ubiquitination assay revealed that TRIM21 promotes ubiquitin-mediated proteasomal degradation of HNF4α. HNF1α transcription is down-regulated as a result of the degradation of HNF4α, an activator for the HNF1α promoter. Therefore, the reduction of key HBV enhancer activators, HNF4α and HNF1α, by TRIM21 resulted in a decline in HBV transcription, ultimately leading to the inhibition of HBV replication.IMPORTANCEDespite extensive research efforts, a definitive cure for chronic hepatitis B remains elusive, emphasizing the persistent importance of this viral infection as a substantial public health concern. Although the risks associated with hepatitis B virus (HBV) infection are well known, host factors capable of suppressing HBV are largely uncharacterized. This study elucidates that tripartite motif-containing protein 21 (TRIM21) suppresses HBV transcription and consequently inhibits HBV replication by downregulating the hepatocyte nuclear factors, which are host factors associated with the HBV enhancers. Our findings demonstrate a novel anti-HBV mechanism of TRIM21 in interferon-gamma-induced anti-HBV activity. These findings may contribute to new strategies to block HBV.
Topics: Humans; Hepatitis B virus; Animals; Mice; Interferon-gamma; Hepatocytes; Virus Replication; Hepatocyte Nuclear Factor 4; Ribonucleoproteins; Hepatitis B; Hep G2 Cells; Cell Line, Tumor
PubMed: 38780244
DOI: 10.1128/jvi.00468-24 -
KLRG1-expressing CD8+ T cells are exhausted and polyfunctional in patients with chronic hepatitis B.PloS One 2024Killer cell lectin-like receptor G1 (KLRG1) has traditionally been regarded as an inhibitory receptor of T cell exhaustion in chronic infection and inflammation....
Killer cell lectin-like receptor G1 (KLRG1) has traditionally been regarded as an inhibitory receptor of T cell exhaustion in chronic infection and inflammation. However, its exact role in hepatitis B virus (HBV) infection remains elusive. CD8+ T cells from 190 patients with chronic hepatitis B were analyzed ex vivo for checkpoint and apoptosis markers, transcription factors, cytokines and subtypes in 190 patients with chronic hepatitis B. KLRG1+ and KLRG1- CD8+ T cells were sorted for transcriptome analysis. The impact of the KLRG1-E-cadherin pathway on the suppression of HBV replication mediated by virus-specific T cells was validated in vitro. As expected, HBV-specific CD8+ T cells expressed higher levels of KLRG1 and showed an exhausted molecular phenotype and function. However, despite being enriched for the inhibitory molecules, thymocyte selection-associated high mobility group box protein (TOX), eomesodermin (EOMES), and Helios, CD8+ T cells expressing KLRG1 produced significant levels of tumour necrosis factor (TNF)-α, interferon (IFN)-γ, perforin, and granzyme B, demonstrating not exhausted but active function. Consistent with the in vitro phenotypic assay results, RNA sequencing (RNA-seq) data showed that signature effector T cell and exhausted T cell genes were enriched in KLRG1+ CD8+ T cells. Furthermore, in vitro testing confirmed that KLRG1-E-cadherin binding inhibits the antiviral efficacy of HBV-specific CD8+ T cells. Based on these findings, we concluded that KLRG1+ CD8+ T cells are not only a terminally exhausted subgroup but also exhibit functional diversity, despite inhibitory signs in HBV infection.
Topics: Humans; CD8-Positive T-Lymphocytes; Lectins, C-Type; Receptors, Immunologic; Hepatitis B, Chronic; Female; Male; Hepatitis B virus; Adult; Middle Aged; Virus Replication; Cadherins; Perforin
PubMed: 38776335
DOI: 10.1371/journal.pone.0303945 -
Cell Communication and Signaling : CCS May 2024Hepatitis B Virus (HBV) is widely recognized as a "metabolic virus" that disrupts hepatic metabolic homeostasis, rendering it one of the foremost risk factors for...
INTRODUCTION
Hepatitis B Virus (HBV) is widely recognized as a "metabolic virus" that disrupts hepatic metabolic homeostasis, rendering it one of the foremost risk factors for hepatocellular carcinoma (HCC). Except for antiviral therapy, the fundamental principles underlying HBV and HBV HCC have remained unchanged, limiting HCC treatment options.
OBJECTIVES
In this study, we aim to identify the distinctive metabolic profile of HBV-associated HCC, with the promise of identifying novel metabolic targets that confer survival advantages and ultimately impede cancer progression.
METHODS
We employed a comprehensive methodology to evaluate metabolic alterations systematically. Initially, we analyzed transcriptomic and proteomic data obtained from a public database, subsequently validating these findings within our test cohort at both the proteomic and transcriptomic levels. Additionally, we conducted a comprehensive analysis of tissue metabolomics profiles, lipidomics, and the activity of the MAPK and AKT signaling pathway to corroborate the abovementioned changes.
RESULTS
Our multi-omics approach revealed distinct metabolic dysfunctions associated with HBV-associated HCC. Specifically, we observed upregulated steroid hormone biosynthesis, primary bile acid metabolism, and sphingolipid metabolism in HBV-associated HCC patients' serum. Notably, metabolites involved in primary bile acid and sphingolipids can activate the MAPK/mTOR pathway. Tissue metabolomics and lipidomics analyses further validated the serum metabolic alterations, particularly alterations in lipid composition and accumulation of unsaturated fatty acids.
CONCLUSION
Our findings emphasize the pivotal role of HBV in HCC metabolism, elucidating the activation of a unique MAPK/mTOR signaling axis by primary bile acids and sphingolipids. Moreover, the hyperactive MAPK/mTOR signaling axis transduction leads to significant reprogramming in lipid metabolism within HCC cells, further triggering the activation of the MAPK/mTOR pathway in turn, thereby establishing a self-feeding circle driven by primary bile acids and sphingolipids.
Topics: Humans; Carcinoma, Hepatocellular; Liver Neoplasms; TOR Serine-Threonine Kinases; Hepatitis B virus; Lipid Metabolism; Male; Lipids; Signal Transduction; MAP Kinase Signaling System; Hepatitis B; Middle Aged; Female
PubMed: 38773448
DOI: 10.1186/s12964-024-01619-5 -
Immunobiology May 2024Activation of the cGAS-STING pathway induces the production of type I interferons, initiating the antiviral immune response, which contributes to the clearance of...
BACKGROUND AND AIMS
Activation of the cGAS-STING pathway induces the production of type I interferons, initiating the antiviral immune response, which contributes to the clearance of pathogens. Previous studies have shown that STING agonists promote hepatitis B virus (HBV) clearance; however, few studies have investigated the effect of activating the cGAS-STING pathway in macrophages on HBV.
METHODS
The polarization status of HBV particle-stimulated RAW264.7 macrophages was analyzed. After stimulation with HBV particles, the analysis focused on determining whether the DNA sensors in RAW264.7 macrophages recognized the viral double-stranded DNA (dsDNA) and evaluating the activation of the cGAS-STING pathway. Coculture of mouse macrophages and hepatocytes harboring HBV was used to study the antiviral activity of HBV-stimulated RAW264.7 macrophages.
RESULTS
After stimulation with HBV particles, HBV relaxed circular DNA (rcDNA) was detected in RAW264.7 macrophages, and the protein expression of phospho-STING, phospho-TBK1, and phospho-IRF3 in the STING pathway was increased, as shown by Western blot analysis, which revealed that M1 polarization of macrophages was caused by increased expression of CD86. RT-PCR analyses revealed elevated expression of M1 macrophage polarization-associated cytokines such as TNFα, IL-1β, iNOS, and IFNα/β. In the coculture experiment, both HBsAg and HBeAg expression levels were significantly decreased in AML12-HBV1.3 cells cocultured with the supernatants of HBV-stimulated RAW264.7 macrophages.
CONCLUSION
The results suggest that macrophages can endocytose HBV particles. Additionally, viral dsDNA can be recognized by DNA pattern recognition receptors, which in turn activate the cGAS-STING pathway, promoting the M1 polarization of macrophages, while no significant M2 polarization is observed. Macrophages stimulated with HBV particles exhibit enhanced antiviral activity against HBV.
Topics: Hepatitis B virus; Animals; Nucleotidyltransferases; Mice; Macrophages; DNA, Viral; Membrane Proteins; RAW 264.7 Cells; Signal Transduction; Hepatitis B; Humans; Macrophage Activation; Hepatocytes; Interferon Regulatory Factor-3
PubMed: 38772101
DOI: 10.1016/j.imbio.2024.152810