Your browser doesn't support javascript.
loading
Montrer: 20 | 50 | 100
Résultats 1 - 20 de 4.828
Filtrer
1.
Virol J ; 21(1): 170, 2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-39090742

RÉSUMÉ

BACKGROUND: Chronic hepatitis B virus (HBV) infection affects around 250 million people worldwide, causing approximately 887,000 deaths annually, primarily owing to cirrhosis and hepatocellular carcinoma (HCC). The current approved treatments for chronic HBV infection, such as interferon and nucleos(t)ide analogs, have certain limitations as they cannot completely eradicate covalently closed circular DNA (cccDNA). Considering that HBV replication relies on host transcription factors, focusing on host factors in the HBV genome may provide insights into new therapeutic targets against HBV. Therefore, understanding the mechanisms underlying viral persistence and hepatocyte pathogenesis, along with the associated host factors, is crucial. In this study, we investigated novel therapeutic targets for HBV infection by identifying gene and pathway networks involved in HBV replication in primary human hepatocytes (PHHs). Importantly, our study utilized cultured primary hepatocytes, allowing transcriptomic profiling in a biologically relevant context and enabling the investigation of early HBV-mediated effects. METHODS: PHHs were infected with HBV virion particles derived from HepAD38 cells at 80 HBV genome equivalents per cell (Geq/cell). For transcriptomic sequencing, PHHs were harvested 1, 2-, 3-, 5-, and 7 days post-infection (dpi). After preparing the libraries, clustering and sequencing were conducted to generate RNA-sequencing data. This data was processed using Bioinformatics tools and software to analyze DEGs and obtain statistically significant results. Furthermore, qRT-PCR was performed to validate the RNA-sequencing results, ensuring consistent findings. RESULTS: We observed significant alterations in the expression patterns of 149 genes from days 1 to 7 following HBV infection (R2 > 0.7, q < 0.05). Functional analysis of these genes identified RNA-binding proteins involved in mRNA metabolism and the regulation of alternative splicing during HBV infection. Results from qRT-PCR experiments and the analysis of two validation datasets suggest that RBM14 and RPL28 may serve as potential biomarkers for HBV-associated HCC. CONCLUSIONS: Transcriptome analysis of gene expression changes during HBV infection in PHHs provided valuable insights into chronic HBV infection. Additionally, understanding the functional involvement of host factor networks in the molecular mechanisms of HBV replication and transcription may facilitate the development of novel strategies for HBV treatment.


Sujet(s)
Virus de l'hépatite B , Hépatocytes , Réplication virale , Humains , Hépatocytes/virologie , Virus de l'hépatite B/génétique , Virus de l'hépatite B/physiologie , Analyse de profil d'expression de gènes , Interactions hôte-pathogène , Cellules cultivées , Réseaux de régulation génique , Hépatite B/virologie , Hépatite B/génétique , Hépatite B chronique/virologie
2.
BMC Infect Dis ; 24(1): 833, 2024 Aug 16.
Article de Anglais | MEDLINE | ID: mdl-39148016

RÉSUMÉ

BACKGROUND: Hepatitis B virus (HBV) and human immunodeficiency virus (HIV) co-infection are significant public health issues, despite the availability of an effective HBV vaccine for nearly three decades and the great progress that has been made in preventing and treating HIV. HBV and HIV both modulate micro-ribonucleic acids (microRNA) expression to support viral replication. The aim of this study was to describe the pattern of microRNA expression in patients coinfected with chronic HBV and HIV with varying disease severity, as indicated by Hepatitis B e antigen (HBeAg) status, HBV viral load, alanine transaminase (ALT) levels, and HIV viral load. METHODS: Plasma microRNAs, specific to HBV, were measured by quantitative real-time polymerase chain reaction (qRT-PCR) in HBV and HIV-negative healthy controls (n = 23) and patients coinfected with chronic HBV-HIV (n = 50). MicroRNA expression levels were compared between patients with high vs low HBV viral load, HBeAg positive vs HBeAg negative, high vs low ALT levels, and high vs low HIV viral load. Additionally, HBV viral load, ALT levels, and HIV viral load were correlated with microRNA expression levels. RESULTS: Significantly higher expression levels of selected microRNAs were observed in chronic HBV-HIV coinfected patients compared to healthy controls. Significantly higher expression levels of hsa-miR-122-5p, hsa-miR-192-5p, and hsa-miR-193b-3p were observed in patients with high HBV viral load compared with low HBV viral load patients, and the levels of these microRNAs were correlated with HBV viral load levels. Significantly higher levels of hsa-miR-15b-5p and hsa-miR-181b-5p were observed in HBeAg-negative patients. CONCLUSION: This study demonstrates the potential use of hsa-miR-15b-5p, hsa-miR-122-5p, hsa-miR-181b-5p, hsa-miR-192-5p and hsa-miR-193b-3p as additional diagnostic biomarkers in chronic HBV disease progression.


Sujet(s)
Co-infection , Infections à VIH , Virus de l'hépatite B , Hépatite B chronique , microARN , Charge virale , Humains , Hépatite B chronique/virologie , Hépatite B chronique/sang , Hépatite B chronique/complications , microARN/sang , microARN/génétique , Infections à VIH/complications , Infections à VIH/virologie , Infections à VIH/sang , Infections à VIH/épidémiologie , Mâle , Co-infection/virologie , Co-infection/épidémiologie , Co-infection/sang , Femelle , Adulte , République d'Afrique du Sud/épidémiologie , Virus de l'hépatite B/génétique , Adulte d'âge moyen , Antigènes e du virus de l'hépatite virale B/sang , Prévalence , Jeune adulte , Alanine transaminase/sang
3.
BMC Infect Dis ; 24(1): 830, 2024 Aug 15.
Article de Anglais | MEDLINE | ID: mdl-39148030

RÉSUMÉ

BACKGROUND AND AIMS: Data on the safety and effectiveness of tenofovir alafenamide (TAF) plus peginterferon-alpha (Peg-IFN-α) in children with chronic hepatitis B (CHB) are lacking. The current study aimed to present the characteristics of four pediatric CHB patients who obtained a functional cure by using TAF and Peg-IFN-α. METHODS: In this case series study initiated in May 2019, ten children who had no clinical symptoms or signs received response-guided (HBV DNA undetectable, hepatitis B e antigen [HBeAg] loss or seroconversion, and hepatitis B surface antigen [HBsAg] loss or seroconversion) and functional cure-targeted (HBsAg loss or seroconversion) TAF (25 mg/d, orally) plus Peg-IFN-α-2b (180 µg/1.73m2, subcutaneously, once weekly) in combination (9/10) or sequential (1/10) therapy. The safety and effectiveness of these treatments were monitored. RESULTS: As of April 2024, four out of ten children obtained a functional cure after a mean of 31.5 months of treatment, and the other six children are still undergoing treatment. These four cured children, aged 2, 4, 8, and 6 years, were all HBeAg-positive and had alanine aminotransferase levels of 80, 47, 114, and 40 U/L; HBV DNA levels of 71200000, 93000000, 8220, and 96700000 IU/mL; and HBsAg levels of 39442.8, 15431.2, 22, and 33013.1 IU/mL, respectively. During treatment, all the children (10/10) experienced mild or moderate adverse events, including flu-like symptoms, anorexia, fatigue, and cytopenia. Notably, growth retardation (8/10) was the most significant adverse event; and it occurred in three cured children (3/4) treated with combination therapy and was present to a low degree in the other cured child (1/4) treated with sequential therapy. Fortunately, all three cured children recovered to or exceeded the normal growth levels at 9 months posttreatment. CONCLUSIONS: TAF plus Peg-IFN-α-2b therapy is potentially safe and effective for pediatric CHB patients, which may provide important insights for future clinical practice and study designs targeting functional cures for children with CHB.


Sujet(s)
Antiviraux , Association de médicaments , Hépatite B chronique , Interféron alpha , Polyéthylène glycols , Protéines recombinantes , Ténofovir , Humains , Ténofovir/usage thérapeutique , Ténofovir/administration et posologie , Ténofovir/analogues et dérivés , Hépatite B chronique/traitement médicamenteux , Hépatite B chronique/virologie , Mâle , Femelle , Antiviraux/usage thérapeutique , Antiviraux/effets indésirables , Antiviraux/administration et posologie , Enfant , Protéines recombinantes/usage thérapeutique , Protéines recombinantes/administration et posologie , Protéines recombinantes/effets indésirables , Polyéthylène glycols/usage thérapeutique , Polyéthylène glycols/effets indésirables , Polyéthylène glycols/administration et posologie , Interféron alpha/usage thérapeutique , Interféron alpha/administration et posologie , Interféron alpha/effets indésirables , Enfant d'âge préscolaire , Résultat thérapeutique , Interféron alpha-2/usage thérapeutique , Interféron alpha-2/administration et posologie , Antigènes de surface du virus de l'hépatite B/sang , Antigènes e du virus de l'hépatite virale B/sang , Virus de l'hépatite B/génétique , Virus de l'hépatite B/effets des médicaments et des substances chimiques , ADN viral/sang , Alanine/usage thérapeutique , Alanine/analogues et dérivés
4.
Int J Mol Sci ; 25(15)2024 Aug 01.
Article de Anglais | MEDLINE | ID: mdl-39125978

RÉSUMÉ

Scientists study the molecular activities of the hepatitis B virus (HBV). However, in vivo experiments are scarce. Some microRNAs are HBV-related, but their exact mechanisms are unknown. Our study provides an up-to-date view of the associations between microRNAs and HBV-DNA levels in chronically infected individuals. We conducted this large-scale research on five databases according to PRISMA guidance. Joanna Briggs Institute tools and Newcastle Ottawa Quality Assessment scores helped with quality evaluations. R 4.2.2 performed statistical computations for the meta-analysis. DIANA-microT 2023 and g:Profiler enriched the predictions of liver genes associated with miR-122 and miR-192-5p. From the 1313 records, we eliminated those irrelevant to our theme, non-article methodologies, non-English entries, and duplicates. We assessed associations between microRNAs and HBV-DNA levels. Overall, the pooled correlations favoured the general idea of the connection between non-coding molecules and viremia levels. MiR-122 and miR-192-5p were the most researched microRNAs, significantly associated with HBV-DNA levels. The connections between miR-122, miR-192-5p, let-7, miR-215, miR-320, and viral loads need further in vivo assessment. To conclude, this study evaluates systematically, for the first time, the correlations between non-coding molecules and viremia levels in patients. Our meta-analysis emphasizes potentially important pathways toward new inhibitors of the viral replication cycle.


Sujet(s)
ADN viral , Virus de l'hépatite B , Hépatite B chronique , microARN , Charge virale , microARN/génétique , Humains , Hépatite B chronique/virologie , Hépatite B chronique/génétique , Virus de l'hépatite B/génétique , ADN viral/génétique
5.
Turk J Gastroenterol ; 35(6): 497-504, 2024 02 29.
Article de Anglais | MEDLINE | ID: mdl-39101697

RÉSUMÉ

Background/Aims: Recent studies revealed that patients with persistent aminotransferase elevations after antiviral treatment had higher risk of hepatic events; yet its underlying causes remain unclear. Our study aimed to investigate the etiologies of persistent aminotransferase elevations in patients treated with nucleos(t)ide analogs (NAs). Materials and Methods: A retrospective study was conducted on chronic hepatitis B (CHB) patients who had been receiving NA treatment for over a year and had an aminotransferase level greater than 40 IU/mL (more than twice, with a 3-month interval) and subsequently underwent a liver biopsy. Results: The study group included 46 patients (34 males) with a mean age of 44.8 ± 20.3 years (range: 24-71 years).The average dura- tion of NA therapy was 3.7 years (1.1-10.6 years). The etiologies of persistant transaminase elevation were categorized into 4 groups: patients with low hepatitis B virus (HBV) viral load (LVL, n = 11); concurrent non-alcoholic fatty liver disease (NAFLD, n = 12); concurrent other liver diseases (OLD, n = 12); and unknown liver dysfunction (ULD, n = 11). The proportion of G ≥ 2 inflammation was significantly higher in the LVL group (90.9%) compared to NAFLD (33.3%), OLD (50%), and ULD (27.2%) groups (P = .012). The hepatitis B e-antigen (HBeAg)-positive group exhibited a younger age (34.5 ± 10.2 vs. 48.1 ± 9.4 years, P < .001), a lower proportion of fibrosis F ≥ 2 (36.3% vs. 77.1%, P = .012), and a higher prevalence of detectable HBV DNA (54.5% vs.14.2%, P = .00632) compared to the HBeAg-negative group. Conclusion: The etiology of persistent aminotransferase elevations in CHB patients undergoing NAs treatment warrants investigation. Besides the commonly observed NAFLD and low HBV viral load, concurrent presence of other liver diseases requires elucidation.The proportion of G≥2 inflammation was higher in the LVL group.


Sujet(s)
Alanine transaminase , Antiviraux , Hépatite B chronique , Charge virale , Humains , Mâle , Hépatite B chronique/traitement médicamenteux , Hépatite B chronique/complications , Hépatite B chronique/sang , Hépatite B chronique/virologie , Femelle , Adulte d'âge moyen , Adulte , Études rétrospectives , Antiviraux/usage thérapeutique , Antiviraux/effets indésirables , Sujet âgé , Jeune adulte , Alanine transaminase/sang , Virus de l'hépatite B , Foie/anatomopathologie , Stéatose hépatique non alcoolique , Nucléosides/usage thérapeutique
6.
World J Gastroenterol ; 30(26): 3261-3263, 2024 Jul 14.
Article de Anglais | MEDLINE | ID: mdl-39086637

RÉSUMÉ

This letter to the editor relates to the study entitled "Tenofovir amibufenamide vs tenofovir alafenamide for treating chronic hepatitis B: A real-world study", which was recently published by Peng et al. Hepatitis B virus infection represents a significant health burden worldwide and can lead to cirrhosis and even liver cancer. The antiviral drugs currently used to treat patients with chronic hepatitis B infection still have many side effects, so it is crucial to identify safe and effective drugs to inhibit viral replication.


Sujet(s)
Antiviraux , Virus de l'hépatite B , Hépatite B chronique , Ténofovir , Humains , Antiviraux/usage thérapeutique , Antiviraux/effets indésirables , Hépatite B chronique/traitement médicamenteux , Hépatite B chronique/virologie , Ténofovir/usage thérapeutique , Ténofovir/analogues et dérivés , Ténofovir/effets indésirables , Virus de l'hépatite B/effets des médicaments et des substances chimiques , Résultat thérapeutique , Réplication virale/effets des médicaments et des substances chimiques , Adénine/analogues et dérivés , Adénine/usage thérapeutique , Adénine/effets indésirables , Alanine/analogues et dérivés , Alanine/usage thérapeutique , Alanine/effets indésirables
7.
Front Immunol ; 15: 1414594, 2024.
Article de Anglais | MEDLINE | ID: mdl-39091506

RÉSUMÉ

Hepatitis B Virus (HBV) is a stealthy and insidious pathogen capable of inducing chronic necro-inflammatory liver disease and hepatocellular carcinoma (HCC), resulting in over one million deaths worldwide per year. The traditional understanding of Chronic Hepatitis B (CHB) progression has focused on the complex interplay among ongoing virus replication, aberrant immune responses, and liver pathogenesis. However, the dynamic progression and crucial factors involved in the transition from HBV infection to immune activation and intrahepatic inflammation remain elusive. Recent insights have illuminated HBV's exploitation of the sodium taurocholate co-transporting polypeptide (NTCP) and manipulation of the cholesterol transport system shared between macrophages and hepatocytes for viral entry. These discoveries deepen our understanding of HBV as a virus that hijacks hepatocyte metabolism. Moreover, hepatic niche macrophages exhibit significant phenotypic and functional diversity, zonal characteristics, and play essential roles, either in maintaining liver homeostasis or contributing to the pathogenesis of chronic liver diseases. Therefore, we underscore recent revelations concerning the importance of hepatic niche macrophages in the context of viral hepatitis. This review particularly emphasizes the significant role of HBV-induced metabolic changes in hepatic macrophages as a key factor in the transition from viral infection to immune activation, ultimately culminating in liver inflammation. These metabolic alterations in hepatic macrophages offer promising targets for therapeutic interventions and serve as valuable early warning indicators, shedding light on the disease progression.


Sujet(s)
Virus de l'hépatite B , Hépatite B chronique , Foie , Macrophages , Humains , Virus de l'hépatite B/immunologie , Virus de l'hépatite B/physiologie , Macrophages/immunologie , Macrophages/métabolisme , Macrophages/virologie , Animaux , Foie/immunologie , Foie/virologie , Foie/métabolisme , Foie/anatomopathologie , Hépatite B chronique/immunologie , Hépatite B chronique/métabolisme , Hépatite B chronique/virologie , Inflammation/immunologie , Inflammation/métabolisme , Hépatocytes/métabolisme , Hépatocytes/immunologie , Hépatocytes/virologie
8.
Clin Transl Sci ; 17(8): e13896, 2024 Aug.
Article de Anglais | MEDLINE | ID: mdl-39119977

RÉSUMÉ

Ruzotolimod (Toll-like receptor 7 (TLR7) agonist, RG7854) is an oral, small molecule immuno-modulator activating the TLR 7 and is being evaluated in patients with CHB. As with other TLR7 agonists, the study drug-related adverse events of flu-like symptoms have been reported in some participants during phase I studies with ruzotolimod. An exploratory analysis of the relationship between pharmacokinetic (PK)/pharmacodynamic (PD) and flu-like symptoms was performed in participants from two phase I studies including both healthy volunteers and NUC-suppressed CHB patients who received either single or multiple ascending doses of orally administered ruzotolimod. Linear and logistic regression were used to explore potential relationships between dose, flu-like symptoms, PK, and PD. Generalized linear regression was performed to predict the probability of flu-like symptoms of all intensities at different RO7011785 (the active metabolite of the double prodrug ruzotolimod) PK exposure. This analysis showed that single or multiple doses of ruzotolimod at ⩾100 mg, the immune PD (IFN-α, neopterin, IP-10, and the transcriptional expression of ISG15, OAS-1, MX1, and TLR7) responses increase with the RO7011785 PK exposure, which increases linearly with the doses from 3 mg to 170 mg of ruzotolimod. The analysis also showed that the probability of flu-like symptoms occurrence increases with PD responses (IFN-α and IP-10). Dose reduction of ruzotolimod can be an effective way to reduce the magnitude of PD response, thus reducing the probability of study drug-related flu-like symptoms occurrence at all intensity in the participants who are highly sensitive to PD activation and intolerant to flu-like symptoms.


Sujet(s)
Volontaires sains , Hépatite B chronique , Récepteur de type Toll-7 , Humains , Récepteur de type Toll-7/agonistes , Mâle , Adulte , Femelle , Adulte d'âge moyen , Hépatite B chronique/traitement médicamenteux , Hépatite B chronique/immunologie , Hépatite B chronique/virologie , Hépatite B chronique/sang , Jeune adulte , Antiviraux/pharmacocinétique , Antiviraux/administration et posologie , Antiviraux/effets indésirables , Grippe humaine/traitement médicamenteux , Grippe humaine/immunologie , Relation dose-effet des médicaments , Adolescent , Administration par voie orale , Composés chimiques organiques
9.
Methods Mol Biol ; 2837: 89-97, 2024.
Article de Anglais | MEDLINE | ID: mdl-39044077

RÉSUMÉ

Chronic hepatitis B virus (HBV) infection is due to the failure of host immune system to resolve the viral infection. Accordingly, restoration or reconstitution of a functional antiviral immune response to HBV is essential to achieve durable control of HBV replication leading to a functional cure of chronic hepatitis B (CHB). Noninfectious subviral particles (SVPs), comprised of HBV surface antigen (HBsAg), are the predominant viral products secreted by HBV-infected hepatocytes. The high levels of SVPs in the circulation induce immune tolerance and contribute to the establishment of chronic HBV infection. The current standard-of-care medications for CHB efficiently suppress HBV replication but fail to reduce the levels of HBsAg in majority of treated patients. Further understanding the mechanisms underlying SVP morphogenesis, secretion and regulation by viral and host cellular factors are critical for the discovery of therapeutics that can inhibit SVP production and/or induce the degradation of HBV envelope proteins. We describe herein a protocol for intracellular SVP detection by a native agarose gel electrophoresis-based particle gel assy. The method is suitable for quantitative detection of intracellular HBV SVPs and can be applied in dissecting the molecular mechanism of SVP morphogenesis and the discovery of antiviral agents targeting SVP formation in hepatocytes.


Sujet(s)
Virus de l'hépatite B , Virion , Virus de l'hépatite B/physiologie , Virus de l'hépatite B/effets des médicaments et des substances chimiques , Humains , Hépatocytes/virologie , Hépatocytes/métabolisme , Antigènes de surface du virus de l'hépatite B/métabolisme , Réplication virale/effets des médicaments et des substances chimiques , Électrophorèse sur gel d'agar/méthodes , Cellules cultivées , Hépatite B chronique/virologie , Hépatite B chronique/traitement médicamenteux
10.
Methods Mol Biol ; 2837: 137-148, 2024.
Article de Anglais | MEDLINE | ID: mdl-39044081

RÉSUMÉ

Hepatitis B virus (HBV) developed highly intricates mechanisms exploiting host resources for its multiplication within a constrained genetic coding capacity. With the aid of a series of classical analytical methods such as ultrafiltration, and Southern and Northern blots, a general framework of HBV life cycle has been established. However, this picture still lacks many key histological contexts which involves pathophysiological changes of hepatocytes, non-parenchymal cells, infiltrated leukocytes, and associated extracellular matrix. Here, we describe a CISH protocol modified from the ViewRNA assay that allows direct visualization of HBV RNA, DNA, and cccDNA in liver tissue of chronic hepatitis B patients. By coupling it with immunohistochemistry and other histological stains, much richer information regarding the HBV-induced pathological changes can be harvested.


Sujet(s)
ADN viral , Virus de l'hépatite B , Hybridation in situ , Foie , ARN viral , Virus de l'hépatite B/génétique , Virus de l'hépatite B/isolement et purification , Humains , Hybridation in situ/méthodes , Foie/virologie , Foie/métabolisme , ADN viral/génétique , ARN viral/génétique , Hépatite B chronique/virologie , Réactifs chromogènes , Immunohistochimie/méthodes , ADN circulaire/génétique , ADN circulaire/analyse
11.
Methods Mol Biol ; 2837: 149-158, 2024.
Article de Anglais | MEDLINE | ID: mdl-39044082

RÉSUMÉ

Chronic hepatitis B virus infection is a major health burden worldwide. Although efficient in maintaining the infection under control, current treatments are unable to fully eradicate the virus due to the persistence of its minichromosome, the so-called cccDNA. In the context of emerging antiviral and combinatorial therapies aiming at decreasing the cccDNA pool or at silencing its transcriptional activity, the detection and quantification of viral RNAs have gained increasing interest as a way to monitor the HBV reservoir. Here, we describe the protocol of the HBV full-length 5'RACE, a technique that allows to define the repertoire of the different HBV RNA species in vitro, intracellularly and extracellularly, and in vivo, in patients' serum in a qualitative or quantitative manner, depending on the choice of the post-analysis methodology.


Sujet(s)
Virus de l'hépatite B , ARN viral , Virus de l'hépatite B/génétique , Humains , ARN viral/génétique , Hépatite B chronique/virologie , Hépatite B chronique/diagnostic , Réaction de polymérisation en chaîne/méthodes
12.
Methods Mol Biol ; 2837: 159-170, 2024.
Article de Anglais | MEDLINE | ID: mdl-39044083

RÉSUMÉ

In recent years, serum hepatitis B virus (HBV) RNA has been identified as a promising noninvasive surrogate biomarker of intrahepatic covalently closed circular DNA (cccDNA), detection of which requires an invasive liver biopsy in patients with chronic HBV infection. It is impractical to detect intrahepatic cccDNA as a routine diagnosis for chronic hepatitis B (CHB) patients in clinical management. Here, we describe a detailed protocol for serum HBV RNA quantification, which can reflect the activity of intrahepatic cccDNA. The procedure includes three major steps: (1) Simultaneous isolation of HBV DNA and RNA from patients' serum, (2) DNase I digestion for removing HBV DNA contamination, and (3) HBV RNA quantification by one-step reverse transcription qPCR.


Sujet(s)
Virus de l'hépatite B , ARN viral , Humains , Virus de l'hépatite B/génétique , Virus de l'hépatite B/isolement et purification , ARN viral/sang , ARN viral/génétique , ARN viral/isolement et purification , ADN viral/sang , ADN viral/génétique , Hépatite B chronique/virologie , Hépatite B chronique/sang , Hépatite B chronique/diagnostic , RT-PCR/méthodes , ADN circulaire/sang , ADN circulaire/isolement et purification , ADN circulaire/génétique , Charge virale/méthodes , Réaction de polymérisation en chaine en temps réel/méthodes
13.
Methods Mol Biol ; 2837: 207-218, 2024.
Article de Anglais | MEDLINE | ID: mdl-39044087

RÉSUMÉ

Mice infected with a recombinant adeno-associated virus carrying a replication-competent hepatitis B virus genome (rAAV-HBV) via the intravenous route establish a persistent HBV replication in hepatocytes and develop immune tolerance. They serve as models to evaluate antiviral immunity and to assess potential therapeutic approaches for chronic HBV infection. Combining selected HBV variants and different mouse genotypes allows for addressing a broad spectrum of research questions. This chapter describes the basic principles of the rAAV-HBV mouse model, rAAV-HBV production and purification methods, and finally, the in vivo application.


Sujet(s)
Dependovirus , Modèles animaux de maladie humaine , Vecteurs génétiques , Virus de l'hépatite B , Réplication virale , Animaux , Dependovirus/génétique , Dependovirus/isolement et purification , Virus de l'hépatite B/génétique , Souris , Vecteurs génétiques/génétique , Vecteurs génétiques/administration et posologie , Humains , Hépatite B chronique/virologie , Hépatite B chronique/immunologie , Hépatite B/virologie , Hépatite B/immunologie
14.
Methods Mol Biol ; 2837: 227-240, 2024.
Article de Anglais | MEDLINE | ID: mdl-39044089

RÉSUMÉ

Virus-specific T cells are critical to mediating viral control; however, Hepatitis B virus (HBV)-specific T cells among chronic Hepatitis B (CHB) patients are functionally exhausted. The inability to consistently measure the ex vivo functionality of HBV-specific T cells has prevented meaningful analysis during antiviral events such as HBeAg seroconversion, hepatic flares, and HBsAg loss. We optimized the traditional IFN-γ ELISpot assay to measure total ex vivo HBV-specific T cell frequencies using CHB PBMCs stimulated with HBV overlapping peptide (OLP) pools. This was then further adapted to assess individual antigen specificity (core, envelop, polymerase, X) and multifunctional HBV-specific T cells using a 3-analyte FluoroSpot assay. This protocol encompasses two major components: (1) PBMC handling/stimulation and (2) assay plate preparation and spot development. By performing this assay, ex vivo CHB patient T cell responses could be assessed longitudinally during immunotherapy or other important clinical events.


Sujet(s)
Test ELISpot , Virus de l'hépatite B , Hépatite B chronique , Lymphocytes T , Humains , Hépatite B chronique/immunologie , Hépatite B chronique/virologie , Virus de l'hépatite B/immunologie , Test ELISpot/méthodes , Lymphocytes T/immunologie , Interféron gamma/métabolisme , Interféron gamma/immunologie , Agranulocytes/immunologie , Agranulocytes/virologie , Agranulocytes/métabolisme
15.
Methods Mol Biol ; 2837: 241-255, 2024.
Article de Anglais | MEDLINE | ID: mdl-39044090

RÉSUMÉ

Fluorescently conjugated antigen-bait systems have been extensively used to identify antigen-specific B cells and probe humoral immunity across different settings. Following this approach, we used HBV antigens to bind the B cell receptor (BCR), permitting antigen-specific B cell detection by flow cytometry. Fluorochromes can either be attached covalently via chemical conjugation to the antigen or attached non-covalently by biotinylating the antigen. Dual-staining antigen-baits (where an antigen is directly conjugated to two distinct fluorochromes) have now been used to identify HBsAg- and HBcAg-specific B cells with a high degree of reliability and specificity. This system can be used to detect and characterize cells ex vivo or adapted to isolate antigen-specific cells using fluorescence-activated cell sorting.


Sujet(s)
Lymphocytes B , Cytométrie en flux , Colorants fluorescents , Antigènes de surface du virus de l'hépatite B , Virus de l'hépatite B , Hépatite B chronique , Humains , Cytométrie en flux/méthodes , Hépatite B chronique/immunologie , Hépatite B chronique/virologie , Virus de l'hépatite B/immunologie , Lymphocytes B/immunologie , Lymphocytes B/métabolisme , Antigènes de surface du virus de l'hépatite B/immunologie , Colorants fluorescents/composition chimique , Coloration et marquage/méthodes , Récepteurs pour l'antigène des lymphocytes B/métabolisme , Récepteurs pour l'antigène des lymphocytes B/immunologie , Antigènes de la nucléocapside du virus de l'hépatite virale B/immunologie
16.
Nature ; 631(8022): 867-875, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38987588

RÉSUMÉ

Chronic hepatitis B virus (HBV) infection affects 300 million patients worldwide1,2, in whom virus-specific CD8 T cells by still ill-defined mechanisms lose their function and cannot eliminate HBV-infected hepatocytes3-7. Here we demonstrate that a liver immune rheostat renders virus-specific CD8 T cells refractory to activation and leads to their loss of effector functions. In preclinical models of persistent infection with hepatotropic viruses such as HBV, dysfunctional virus-specific CXCR6+ CD8 T cells accumulated in the liver and, as a characteristic hallmark, showed enhanced transcriptional activity of cAMP-responsive element modulator (CREM) distinct from T cell exhaustion. In patients with chronic hepatitis B, circulating and intrahepatic HBV-specific CXCR6+ CD8 T cells with enhanced CREM expression and transcriptional activity were detected at a frequency of 12-22% of HBV-specific CD8 T cells. Knocking out the inhibitory CREM/ICER isoform in T cells, however, failed to rescue T cell immunity. This indicates that CREM activity was a consequence, rather than the cause, of loss in T cell function, further supported by the observation of enhanced phosphorylation of protein kinase A (PKA) which is upstream of CREM. Indeed, we found that enhanced cAMP-PKA-signalling from increased T cell adenylyl cyclase activity augmented CREM activity and curbed T cell activation and effector function in persistent hepatic infection. Mechanistically, CD8 T cells recognizing their antigen on hepatocytes established close and extensive contact with liver sinusoidal endothelial cells, thereby enhancing adenylyl cyclase-cAMP-PKA signalling in T cells. In these hepatic CD8 T cells, which recognize their antigen on hepatocytes, phosphorylation of key signalling kinases of the T cell receptor signalling pathway was impaired, which rendered them refractory to activation. Thus, close contact with liver sinusoidal endothelial cells curbs the activation and effector function of HBV-specific CD8 T cells that target hepatocytes expressing viral antigens by means of the adenylyl cyclase-cAMP-PKA axis in an immune rheostat-like fashion.


Sujet(s)
Lymphocytes T CD8+ , Hépatite B chronique , Foie , Animaux , Humains , Mâle , Souris , Lymphocytes T CD8+/enzymologie , Lymphocytes T CD8+/immunologie , Lymphocytes T CD8+/métabolisme , Lymphocytes T CD8+/anatomopathologie , Modulateur de l'élément de réponse à l'AMP cyclique/métabolisme , Cyclic AMP-Dependent Protein Kinases/métabolisme , Virus de l'hépatite B/immunologie , Hépatite B chronique/immunologie , Hépatite B chronique/virologie , Hépatocytes/immunologie , Hépatocytes/virologie , Foie/immunologie , Foie/virologie , Phosphorylation , Transduction du signal , Activation des lymphocytes
17.
Rev Med Virol ; 34(4): e2570, 2024 Jul.
Article de Anglais | MEDLINE | ID: mdl-38964866

RÉSUMÉ

The question of whether patients in the immune-tolerant (IT) phase of chronic hepatitis B virus (HBV) infection should undergo antiviral therapy and determine the optimal regimen remains unclear. A comprehensive search of PubMed, Embase, MEDLINE, Cochrane Library, and Wanfang Data from inception to 5 December 2023, was conducted. Studies reporting on key outcomes such as HBV DNA undetectability, HBeAg loss or seroconversion, HBsAg loss or seroconversion, and hepatocellular carcinoma (HCC) incidence in patients in the IT phase of chronic HBV infection were included. In total, 23 studies were incorporated. Approximately 4% of patients in the IT phase achieved spontaneous HBeAg loss over 48 weeks of follow-up. Antiviral therapy demonstrated a favourable impact on HBV DNA negative conversion (Children: risk ratios [RR] = 6.83, 95% CI: 2.90-16.05; Adults: RR = 25.84, 95% CI: 6.47-103.31) and HBsAg loss rates (Children: RR = 9.49, 95% CI: 1.74-51.76; Adults: RR = 7.35, 95% CI: 1.41-38.27) for patients in the IT phase. Subgroup analysis revealed that in adult patients in the IT phase, interferon plus nucleos(t)ide analogues (NA)-treated patients exhibited a higher pooled rate of HBsAg loss or seroconversion than those treated with NA monotherapy (9% vs. 0%). Additionally, the pooled annual HCC incidence for patients in the IT phase was 3.03 cases per 1000 person-years (95% CI: 0.99-5.88). Adult patients in the IT phase had a significantly lower HCC incidence risk than HBeAg-positive indeterminate phase patients (RR = 0.46, 95% CI: 0.32-0.66), with no significant differences observed between IT and immune-active phases. Presently, there is insufficient evidence solely based on reducing the risk of HCC incidence, to recommend treating patients in the IT phase of chronic HBV infection. However, both adult and paediatric patients in the IT phase responded well to antiviral therapy, showing favourable rates of HBsAg loss or seroconversion.


Sujet(s)
Antiviraux , Carcinome hépatocellulaire , Antigènes e du virus de l'hépatite virale B , Hépatite B chronique , Tumeurs du foie , Humains , Carcinome hépatocellulaire/épidémiologie , Carcinome hépatocellulaire/virologie , Carcinome hépatocellulaire/immunologie , Hépatite B chronique/complications , Hépatite B chronique/traitement médicamenteux , Hépatite B chronique/virologie , Hépatite B chronique/épidémiologie , Hépatite B chronique/immunologie , Tumeurs du foie/épidémiologie , Tumeurs du foie/virologie , Tumeurs du foie/immunologie , Antiviraux/usage thérapeutique , Antigènes e du virus de l'hépatite virale B/sang , Antigènes e du virus de l'hépatite virale B/immunologie , Virus de l'hépatite B/immunologie , Incidence , Antigènes de surface du virus de l'hépatite B/sang , Antigènes de surface du virus de l'hépatite B/immunologie , ADN viral/sang , Tolérance immunitaire , Résultat thérapeutique , Séroconversion
18.
Front Public Health ; 12: 1380771, 2024.
Article de Anglais | MEDLINE | ID: mdl-38952725

RÉSUMÉ

Serological pattern of simultaneous positivity for hepatitis B surface antigen (HBsAg) and antibody against HBsAg (anti-HBs) is considered a specific and atypical phenomenon among patients with chronic hepatitis B virus (HBV) infection, especially in pediatric patients. Unfortunately, there is limited understanding of the clinical and virological characteristics among children having chronic HBV infection and the coexistence of HBsAg and anti-HBs. Hence, our objective was to determine the prevalence of coexistent HBsAg and anti-HBs and to explore the associated clinical and virological features in this patient population. The researchers conducted a retrospective cohort study on the 413 pediatric patients with chronic HBV infection from December 2011 to June 2022. The patients were stratified into two groups based on their anti-HBs status. Demographic, serum biochemical and virological parameters of two group were compared. Of the total 413 enrolled subjects, 94 (22.8%) were tested positive for both HBsAg and anti-HBs. Patients with anti-HBs were younger and demonstrated significantly higher ratio of albumin to globulin (A/G), elevated serum levels of alanine transaminase (ALT), lower ratio of aspartate transaminase (AST)/ALT (AST/ALT) and reduced serum levels of globulin, HBsAg and HBV DNA, Additionally, these patients were more likely to show coexistent HBeAg and anti-HBe when compared to patients without anti-HBs. The results of multivariate logistical analysis revealed that AST/ALT, serum levels of globulin and HBsAg were negatively associated with coexistence of HBsAg and anti-HBs. Our data demonstrated a considerable prevalence of coexisting HBsAg and anti-HBs in pediatric patients. Children with this specific serological pattern were commonly of a younger age, seemly predisposing them to early liver impairment and lower HBV replication activity.


Sujet(s)
Anticorps de l'hépatite B , Antigènes de surface du virus de l'hépatite B , Hépatite B chronique , Humains , Mâle , Antigènes de surface du virus de l'hépatite B/sang , Femelle , Enfant , Études rétrospectives , Hépatite B chronique/virologie , Hépatite B chronique/épidémiologie , Anticorps de l'hépatite B/sang , Enfant d'âge préscolaire , Virus de l'hépatite B/immunologie , Alanine transaminase/sang , Adolescent , ADN viral/sang , Chine/épidémiologie , Prévalence , Aspartate aminotransferases/sang
19.
PLoS One ; 19(7): e0305753, 2024.
Article de Anglais | MEDLINE | ID: mdl-38985789

RÉSUMÉ

Hepatitis B virus (HBV) belongs to the genus Orthohepadnavirus, of Hepadnaviridae family, smallest human deoxyribonucleic acid (DNA) virus with 3200 bp in a partially double-stranded circular DNA. Globally, about 2 billion people are infected with over 65 million of the chronically infected residing in Africa. Ten HBV genotypes (A-J) have been reported across the globe. Based on the World Health Organization (WHO) African Regions including Kenya have high HBV prevalence rates yet the data on prevalence rates of the various HBV genotypes and their associated biomarkers is very scanty. A cross-sectional descriptive study with purposive sampling was conducted in which a census of patients with chronic Hepatitis B (CHB) with history >6-month were reviewed for eligibility. Demographics data was abstracted from patient files and blood samples drawn for genotyping, viral load using Rotor gene Q Polymerase Chain Reaction (PCR) equipment, Hepatitis B surface Antigen (HBsAg), Hepatitis B envelope antigen (HbeAg) and Hepatitis B core antibody (Anti-HBc) using Cobas e411 machine. Out of a total of 83 patients, 43 (52%) were eligible; males 29 (67.4%), females 14 (32.6%) with mean ages of 35.1±10.8 and 34.3±9.3 respectively. Genotypes A were 34(79.1%), B were 5(11.6%), C-D were 0 while E-J were 9(20.9%). All cases of genotype B were associated with co-infection of genotype A. Majority were HBeAg negative with HBV DNA >10 IU/ml (81.4% and 86.0% respectively) with distribution among all the genotypes. Across genotypes, viral load mean percentage comparisons were: A vs. A/B = 2600 (p = 0.09), A vs. E-J = 5260 (p = 0.09) and A/B vs. E-J = 200 (p = 0.28). The most prevalent genotype was A followed by mixed co-infection of genotype A/B. Genotype A was associated with HBV DNA viral loads > 10IU/ml and high rates of HBeAg negativity. Genotypes E-J were also detected though not characterized.


Sujet(s)
Génotype , Virus de l'hépatite B , Hépatite B chronique , Humains , Mâle , Femelle , Virus de l'hépatite B/génétique , Virus de l'hépatite B/isolement et purification , Adulte , Prévalence , Kenya/épidémiologie , Études transversales , Adulte d'âge moyen , Hépatite B chronique/virologie , Hépatite B chronique/épidémiologie , Charge virale , Antigènes de surface du virus de l'hépatite B/sang , Antigènes de surface du virus de l'hépatite B/génétique , Antigènes e du virus de l'hépatite virale B/sang , Hôpitaux d'enseignement , ADN viral/génétique , Orientation vers un spécialiste , Jeune adulte
20.
Int J Med Sci ; 21(9): 1661-1671, 2024.
Article de Anglais | MEDLINE | ID: mdl-39006848

RÉSUMÉ

Background and aim: Patients with chronic hepatitis B patients (CHB) with low-level viremia (LLV) are not necessarily at low risk of developing hepatocellular carcinoma (HCC). The question of whether CHB patients with LLV require immediate antiviral agent (AVT) or long-term AVT remains controversial. The study aims to investigate the risk of HCC development and the risk factors in CHB patients with LLV and construct a nomogram model predicting the risk of HCC. Methods: We conducted a retrospective cohort study that enrolled 16,895 CHB patients from January 2008 to December 2020. The patients were divided into three groups for comparison: the LLV group, maintained virological response (MVR) group and HBV-DNA>2000 group. The cumulative incidence of progression to HCC was assessed. Cox regression analysis was performed to determine the final risk factors, and a nomogram model was constructed. The 10-fold Cross-Validation method was utilized for internal validation. Results: A total of 408 new cases of HCC occurred during the average follow-up period of 5.78 years. The 3, 5, and 10-year cumulative HCC risks in the LLV group were 3.56%, 4.96%, and 9.51%, respectively. There was a significant difference in the cumulative risk of HCC between the HBV-DNA level > 2000 IU/mL and LLV groups (p = 0.049). Independent risk factors for HCC development in LLV group included male gender, age, presence of cirrhosis, and platelets count. The Area Under the Curve (AUC) values for the 3-year and 5-year prediction from our HCC risk prediction model were 0.75 and 0.76, respectively. Conclusion: Patients with LLV and MVR are still at risk for developing HCC. The nomogram established for CHB patient with LLV, incorporating identified significant risk factors, serves as an effective tool for predicting HCC-free outcomes. This nomogram model provides valuable information for determining appropriate surveillance strategies and prescribing AVT.


Sujet(s)
Carcinome hépatocellulaire , Virus de l'hépatite B , Hépatite B chronique , Tumeurs du foie , Nomogrammes , Virémie , Humains , Carcinome hépatocellulaire/virologie , Carcinome hépatocellulaire/épidémiologie , Carcinome hépatocellulaire/anatomopathologie , Tumeurs du foie/virologie , Tumeurs du foie/épidémiologie , Tumeurs du foie/étiologie , Mâle , Hépatite B chronique/complications , Hépatite B chronique/virologie , Femelle , Adulte d'âge moyen , Études rétrospectives , Facteurs de risque , Virémie/complications , Adulte , Virus de l'hépatite B/isolement et purification , Antiviraux/usage thérapeutique , Incidence , ADN viral/sang
SÉLECTION CITATIONS
DÉTAIL DE RECHERCHE