Antigen Hepatitis Research Articles

Dendritic cells derived from induced pluripotent stem cells and stimulated by antigens of hepatitis C virus efficiently activate T-lymphocytes

Dendritic cells derived from induced pluripotent stem cells and stimulated by antigens of hepatitis C virus efficiently activate T-lymphocytes

Clinical performance of Circulating HBV RNA and iTACT-HBcrAg Assays in HBeAg-negative and HBsAg-cleared Chronic Hepatitis B Patients.

Hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg) have been reported to reflect the transcriptional activity of covalently closed circular HBV DNA. We retrospectively investigated the proportions of quantifiable serum HBV RNA and immunoassay for total antigen including complex via pretreatment-hepatitis B core-related antigen (iTACT-HBcrAg) in chronic hepatitis B patients negative for hepatitis B e antigen (HBeAg) and/or with hepatitis B surface antigen (HBsAg) seroclearance. This study included 246 HBeAg-negative HBV-infected patients, who comprised 13 with liver cirrhosis (LC, the LC group), 118 chronic hepatitis (CH, the CH group), and 115 inactive carriers (IC, the IC group), and 44 patients with HBsAg seroclearance. iTACT-HBcrAg and HBV RNA levels were determined using stored serum samples. Higher proportions of the patients had quantifiable iTACT-HBcrAg than HBV RNA in all groups of HBeAg-negative patients (iTACT-HBcrAg: 84.6%, 90.7%, 35.7%, HBV RNA: 23.1%, 26.3%, 14.8%, for the LC, CH, IC groups). With HBsAg seroclearance (HBsAg <0.05 IU/mL), the proportions of quantifiable samples for HBV RNA were also lower than iTACT-HBcrAg (0% for HBV RNA). Thus, iTACT-HBcrAg was more often detectable than circulating HBV RNA in this study population. Further long-term prospective evaluation of iTACT-HBcrAg is desirable for its utilization in clinical practice.

Design and Synthesis of Polyphenolic Imidazo[4,5-c]quinoline Derivatives to Modulate Toll Like Receptor-7 Agonistic Activity and Adjuvanticity.

TLR-7/8 agonists are a well-known class of vaccine adjuvants, with a leading example now included in Covaxin, a licensed human COVID-19 vaccine. This thereby provides the opportunity to develop newer, more potent adjuvants based on structure-function studies of these classes of compounds. Imidazoquinoline-based TLR7/8 agonists are the most potent, but when used as a vaccine adjuvant side effects can arise due to diffusion from the injection site into a systemic circulation. In this work, we sought to address this issue through structural modifications in the agonists to enhance their adsorption capacity to the classic adjuvant alum. We selected a potent TLR7-selective agonist, BBIQ (EC50 = 0.85 μM), and synthesized polyphenolic derivatives to assess their TLR7 agonistic activity and adjuvant potential alone or in combination with alum. Most of the phenolic derivatives were more active than BBIQ and, except for 12b, all were TLR7 specific. Although the synthesized compounds were less active than resiquimod, the immunization data on combination with alum, specifically the IgG1, IgG2b and IgG2c responses, were superior in comparison to BBIQ as well as the reference standard resiquimod. Compound 12b was 5-fold more potent (EC50 = 0.15 μM in TLR7) than BBIQ and induced double the IgG response to SARS-CoV-2 and hepatitis antigens. Similarly, compound 12c (EC50 = 0.31 μM in TLR7) was about 3-fold more potent than BBIQ and doubled the IgG levels. Even though compound 12d exhibited low TLR7 activity (EC50 = 5.13 μM in TLR7), it demonstrated superior adjuvant results, which may be attributed to its enhanced alum adsorption capability as compared with BBIQ and resiquimod. Alum-adsorbed polyphenolic TLR7 agonists thereby represent promising combination adjuvants resulting in a balanced Th1/Th2 immune response.

WED-362 Rapid hepatitis B surface antigen reduction in chronic hepatitis B virus infection: preliminary results from a phase I b study evaluating multiple ascending doses of HT-102, a neutralizing antibodies against hepatitis B surface antigen in chronic hepatitis B patients

WED-362 Rapid hepatitis B surface antigen reduction in chronic hepatitis B virus infection: preliminary results from a phase I b study evaluating multiple ascending doses of HT-102, a neutralizing antibodies against hepatitis B surface antigen in chronic hepatitis B patients

Kinetics of the hepatitis B core-related antigen and treatment responses in chronic hepatitis B patients treated with tenofovir alafenamide.

An association between hepatitis B core-related antigen (HBcrAg) kinetics and hepatocarcinogenesis during nucleoside (t)id analog (NA) treatment has recently been reported. HBcrAg kinetics and factors associated with HBcrAg response during tenofovir alafenamide (TAF) administration remain unclear. In this multicenter retrospective study, we aimed to clarify the efficacy and safety of TAF in treatment-naïve patients with chronic hepatitis B, focusing on the reduction in HBcrAg levels. Patients were treated with TAF monotherapy for 96weeks, and the kinetics of HBcrAg during treatment and the factors associated with HBcrAg response (defined as a change in HBcrAg of -1logIU/mL from baseline) were evaluated. The study population comprised 241 patients, 36.9% of whom were HBeAg-positive. The median baseline HBcrAg level was 4.7logIU/mL. The median change in HBcrAg from baseline was -1.1logIU/mL at 96weeks after treatment. The HBcrAg response rate at 96weeks was 56.6% (43/76). Multivariate analysis revealed high alanine transaminase level as an independent baseline factor associated with HBcrAg response at 96weeks of treatment (p=4.53×10-6). No correlation was found between the HBcrAg and hepatitis B surface antigen kinetics in patients treated with TAF monotherapy. In TAF monotherapy for patients with chronic hepatitis B, HBcrAg levels were significantly decreased and baseline alanine transaminase level is an important factor associated with HBcrAg reduction. As no correlation was found between HBcrAg and reduced hepatitis B surface antigen levels in this study, HBcrAg kinetics in addition to hepatitis B surface antigen may need to be monitored during TAF treatment.

Toward a SARS-CoV-2 VLP Vaccine: HBc/G as a Carrier for SARS-CoV-2 Spike RBM and Nucleocapsid Protein-Derived Peptides.

Virus-like particles (VLPs) offer an attractive possibility for the development of vaccines. Recombinant core antigen (HBc) of Hepatitis B virus (HBV) was expressed in different systems, and the E. coli expression system was shown to be effective for the production of HBc VLPs. Here, we used HBc of the HBV genotype G (HBc/G) as a technologically promising VLP carrier for the presentation of spike RBM and nucleocapsid protein-derived peptides of the SARS-CoV-2 Delta variant for subsequent immunological evaluations of obtained fusion proteins. The major immunodominant region (MIR) of the HBc/G protein was modified through the insertion of a receptor binding motif (RBM) from the S protein or B-cell epitope-containing peptide from the N protein. The C-terminus of the two truncated HBc/G proteins was used for the insertion of a group of five cytotoxic T lymphocyte (CTL) epitopes from the N protein. After expression in E. coli, the MIR-derived proteins were found to be insoluble and were recovered through step-wise solubilization with urea, followed by refolding. Despite the lack of correct VLPs, the chimeric proteins induced high levels of antibodies in BALB/c mice. These antibodies specifically recognized either eukaryotically expressed hRBD or bacterially expressed N protein (2-220) of SARS-CoV-2. CTL-epitope-containing proteins were purified as VLPs. The production of cytokines was analyzed through flow cytometry after stimulation of T-cells with target CTL peptides. Only a protein with a deleted polyarginine (PA) domain was able to induce the specific activation of T-cells. At the same time, the T-cell response against the carrier HBc/G protein was detected for both proteins. The neutralization of SARS-CoV-2 pseudotyped murine retrovirus with anti-HBc/G-RBM sera was found to be low.

Comparison between Quantitative Hepatitis B DNA and HBeAg Positivity to Detect Active Viral Replication among Patients with Hepatitis B infection in a Tertiary Care Hospital

To study the correlation between quantitative Hepatitis B DNA and HBeAg positivity among HBsAg positive patients in a tertiary care hospital. To detect HBsAg, HBeAg levels by CMIA (Chemiluminescent microparticle immunoassay). To perform quantitative Hepatitis B virus DNA assay using Real Time Polymerase Chain Reaction. The study took place between July and December 2022 for 6 months. Sixty four patients were included in the study for whom HBsAg was positive by CMIA and for whom HBeAg (detected by CMIA) and Hepatitis B Virus DNA by quantitative Real Time PCR was performed. Of the 64 HBsAg reactive patients, the ‘e’ antigen of Hepatitis B virus was positive in six patients. In all the six HBeAg positive patients, HBV DNA was detected with a range of 78-10,288 IU/ml with 66% having levels more than 2000 IU/ml and requiring treatment. Among the 58 patients who were negative for the ‘e’ antigen of Hepatitis B virus, the Hepatitis B Viral DNA was detected in 27 patients with a range of 10-1,76,000 IU/ml, with 21% of patients having levels more than 2000 IU/ml. HBeAg is a good serological test to detect viral replication. However, it alone might not be sufficient as quantitative HBV DNA levels are more accurate and it does identify more patients who may require treatment.

The Study of Performance of a Nanoribbon Biosensor, Sensitized with Aptamers and Antibodies, upon Detection of Core Antigen of Hepatitis C Virus.

The development of highly sensitive diagnostic systems for the early revelation of diseases in humans is one of the most important tasks of modern biomedical research, and the detection of the core antigen of the hepatitis C virus (HCVcoreAg)-a protein marker of the hepatitis C virus-is just the case. Our study is aimed at testing the performance of the nanoribbon biosensor in the case of the use of two different types of molecular probes: the antibodies and the aptamers against HCVcoreAg. The nanoribbon sensor chips employed are based on "silicon-on-insulator structures" (SOI-NR). Two different HCVcoreAg preparations are tested: recombinant β-galactosidase-conjugated HCVcoreAg ("Virogen", Watertown, MA, USA) and recombinant HCVcoreAg ("Vector-Best", Novosibirsk, Russia). Upon the detection of either type of antigen preparation, the lowest concentration of the antigen detectable in buffer with pH 5.1 was found to be approximately equal, amounting to ~10-15 M. This value was similar upon the use of either type of molecular probes.

SAT-162 - The different immune response of B cells specific for hepatitis B virus core and envelope antigen in chronic hepatitis B patients with pegylated interferon-alpha treatment

SAT-162 - The different immune response of B cells specific for hepatitis B virus core and envelope antigen in chronic hepatitis B patients with pegylated interferon-alpha treatment

CD8 T cell-mediated depletion of HBV surface-antigen-expressing, bilineal-differentiated liver carcinoma cells generates highly aggressive escape variants

ABSTRACT The expression of viral antigens in chronic hepatitis B virus (HBV) infection drives continuous liver inflammation, one of the main risk factors to develop liver cancer. HBV developed immune-suppressive functions to escape from the host immune system, but their link to liver tumor development is not well understood. Here, we analyzed if and how HBV surface antigen (HBs) expression in combined hepatocellular-cholangiocarcinoma (cHCC/iCCA) cells influences their antigenicity for CD8 T cells. We randomly isolated liver tumor tissues from AlfpCre+-Trp53fl/fl/Alb-HBs+ tg mice and established primary carcinoma cell lines (pCCL) that showed a bilineal (CK7+/HNF4α+) cHCC/iCCA phenotype. These pCCL uniformly expressed HBs (HBshi), and low levels of MHC-I (MHC-Ilo), and were transiently convertible to a high antigenicity (MHC-Ihi) phenotype by IFN-γ treatment. HBshi/pCCL induced HBs/(Kb/S190–197)-specific CD8 T cells and developed slow-growing tumors in subcutaneously transplanted C57Bl/6J (B6) mice. Interestingly, pCCL-ex cells, established from HBshi/pCCL-induced and re-explanted tumors in B6 but not those in immune-deficient Rag1−/− mice showed major alterations, like an MHC-Ihi phenotype, a prominent growth-biased gene expression signature, a significantly decreased HBs expression (HBslo) and a switch to fast-growing tumors in re-transplanted B6 or PD-1−/− hosts with an unlocked PD-1/PD-L1 control system. CD8 T cell-mediated elimination of HBshi/pCCL, together with the attenuation of the negative restraints of HBs in the tumor cells, like ER-stress, reveals a novel mechanism to unleash highly aggressive HBslo/pCCL-ex immune-escape variants. Under certain conditions, HBs-specific CD8 T-cell responses thus potentiate tumor growth, an aspect that should be considered for therapeutic vaccination strategies against chronic HBV infection and liver tumors.

Development of lipid nano particles RNA vaccine against hepatitis B surface antigens of hepatitis B virus

Development of lipid nano particles RNA vaccine against hepatitis B surface antigens of hepatitis B virus

The effectiveness of hepatitis B vaccine in toddlers based on the five-year period national basic health research (Riskesdas 2007, 2013 and 2018) in Indonesia.

Hepatitis B is a viral infection that has a high prevalence in Indonesia. The Ministry of Health of Indonesia has conducted a national vaccination program for hepatitis B. In order to evaluate the success of the hepatitis B vaccination in Indonesia, a community study based on basic health research (Riskesdas) was performed nationwide since 2007 for five year period in 2007, 2013, and 2018. Further statistical analysis was performed specifically for the children under 59 months old (toddlers) immunized in both urban and rural areas in 2007, 2013, and 2018 based on certain characteristics by examining antibodies against HBsAg (anti-HBs), IgG antibodies against the core antigen (HBcAb), surface antigen (HBsAg) of hepatitis B virus (HBV). The data obtained from the data management laboratory of Ministry of Health, Indonesia, was analyzed with Bivariate analysis with continuity correction chi-square or Pearson chi-square using Stata software version 16. This study showed an increase in hepatitis B coverage of complete immunization (30% in 2007, 60.3% in 2013, and 57% in 2018), which was also influenced by mothers' level of education (Pearson chi-square , p ¡ 0.05) and access to health service points within 30 minutes (OR = 1.3-2.8, p ¡ 0.05). The trend of the percentage of immune status (anti-HBs) was increased (41.8% in 2007; 56.1% in 2013; and 79.1% in 2018). The higher anti-HBs was found in complete hepatitis B immunization status (OR = 1.5-2, p ¡ 0.05) and in good nutritional status (p ¡ 0.05). However, the anti-HBs was found decreased with increasing age (p ¡ 0.05). The trend of positive HBcAb (exposure to HBV infection) showed a decrease gradually of almost ten times from 2007 (8.6%-13.5%) compared to 2013 (2.6%-11.1%) and 2018 (1.1%-2%). Urban areas were at higher risk of hepatitis B exposure (OR = 1.4-2.2) than rural areas (OR = 0.37-0.80). The HBsAg data were only available in 2013 and 2018. Riskesdas data analysis showed the prevalence of hepatitis B (HBsAg) was lower in complete immunization status than that in incomplete one (p ¡ 0.05), but with an increase from 3.9% (2013) to 9.3% (2018), possibly due to inappropriate implementation of birth dose immunization or a vaccine-escape mutant from the HBV variants. The effectiveness of hepatitis B vaccine obtained from the three Riskesdas periods in Indonesia showed an improvement, with an increase in immune status, reduced exposure to HBV and a lower prevalence of hepatitis B in children with complete vaccination. However, there is still an increase in hepatitis B infection, especially in urban areas. Therefore, a long-term evaluation of immunization coverage especially ensuring that the initial dose of immunization was given within the first 24 h of birth, HBsAg and HBcAb, nutritional status, genomic surveillance of HBV, and other aspects of program quality evaluation are needed to ensure that elimination efforts have been implemented properly.

Recovery of host adaptive immune function promoted the reduction of hepatitis B surface antigen in nucleoside analog-experienced chronic hepatitis B patients with low hepatitis B surface antigen levels.

Hepatitis B surface antigen (HBsAg) seroclearance is an optimal therapeutic endpoint, as it reflects the amount of covalently closed circular DNA. The exact mechanisms that contribute to HBsAg reduction are not completely understood. We evaluated adaptive immunity in nucleoside analog-experienced chronic hepatitis B (CHB) patients with low HBsAg levels who received oral antiviral therapy. One hundred and ninety-five CHB patients had hepatitis B virus (HBV) DNA≤1000IU/ml and HBsAg<3000IU/ml for longer than one year of antiviral therapy. According to HBsAg levels, they were divided into Group 1 (HBsAg reduction≥0.5 log10) and Group 2 (HBsAg reduction<0.5 log10). Cytokines, adaptive immune cells, and molecular markers in peripheral blood were detected at follow-up times. In total, 38 (19.5%) of the 195 patients achieved HBsAg reduction≥0.5 log10. IL4, IL5, IL10, TGF β, IL17, and PD-1 decreased gradually in these patients. HBsAg reduction had a link to the change in ICOSL+CD19+ B cells and CD40L+CXCR5+CD4+ Tfh cells. More CD8+ naive T lymphocytes differentiated into CD4+ TCMs, CD8+ TCMs and CD8+ TEMs in Group 1. Meanwhile, Group 1 exhibited elevated Th1 and Th1/Th2 levels and reduced levels of Treg versus those in Group 2. With the reduction in HBsAg, the imbalance of T-cell subsets was partially corrected; the immune activity of T cells was enhanced, and the state of immune exhaustion was alleviated to a certain extent.

A longitudinal study to detect hepatitis B surface and core-related antigens in chronic hepatitis B patients with hepatitis B surface antigen seroclearance using highly sensitive assays.

This study aimed to evaluate the usefulness of two novel assays, namely the iTACT-hepatitis B surface antigen (iTACT-HBsAg) and iTACT-hepatitis B core-related antigen (iTACT-HBcrAg) assays, in chronic hepatitis B (CHB) patients with HBsAg seroclearance (SC) documented by standard assays. HBsAg and HBcrAg were measured by the two iTACT-assays in 556 serial sera collected from 96 CHB patients at 7 different time points spanning from 5 years before to 10 years after SC and 120 HBsAg-negative, anti-HBc-positive individuals. As controls, 60 seronegative individuals, who were negative for HBsAg, anti-HBc and anti-HBs, were tested. Using the iTACT-assays, HBsAg was detectable in 154/418 (36.8%) samples collected after SC. HBcrAg was detectable in 78.3% and 65.9% of samples collected before and after SC, respectively. The detectability rates of both HBsAg and HBcrAg progressively decreased over time after SC. At 10 years after SC, 20.4% and 64.5% of the patients still had detectable HBsAg and HBcrAg, respectively. 66 (71%) patients had detectable HBsAg and/or HBcrAg. Among the 120 HBsAg-negative, anti-HBc-positive individuals, 11 (9.2%) and 4 (3.3%) had detectable HBsAg and HBcrAg respectively. Both HBsAg and HBcrAg were undetectable in the controls. The iTACT assays detected a low level of HBsAg and/or HBcrAg in >70% of patients even at 10 years after SC, suggesting that CHB patients with SC still harbour a low level of HBV protein expression. The clinical significance of detectable viral proteins after SC with regard to disease progression and HBV reactivation deserves further investigations.

The Clinical and Laboratory Profiles of Immunocompetent Patients With Short-Duration Fever With Neutropenia in a Tertiary Care Hospital in Pune, India.

Background Management of a febrile patient is based on understanding the pathophysiology of an abnormal temperature and temperature regulation, impacts of fever, and its treatment. In the current study, we aimed to characterize and compare the epidemiological, etiologic, microbiological, serological, clinical, and outcome traits of febrile patientswith acute neutropenia admitted to a tertiary care center in Western Maharashtra. Methods Adult patientswith a history of fever of less than two weeks' duration and without any immunosuppressive state were screened with predefined inclusion and exclusion criteria. General anddemographic information (age andgender), and clinical examinations (type and duration of fever) were recorded. Biochemical, hematologic(total and differential cell counts), and immunologicmeasurements (rapid malaria, dengue, Leptospira, and viral hepatitis antigen antibodies) were performed. Data were analyzed using an appropriate statistical package. Results A total of 403 (214 males) young adults (aged: 29±11 years) with clinical presentation of fever were studied. The majority (n=361, 89.6%) had low-grade continuous fever with an average duration of 3±1 (mean±standard deviation (SD)) days. Headache and myalgia were the common symptoms present, and patients had an average hospital stay of 4±1 days. Dengue (55%) was the most common cause of febrile neutropenia, and all patients recovered well without antibiotics and granulocyte colony-stimulating factor. The mean C-reactive protein (CRP) level was 61.4±4.4 mg/L. CRP and procalcitonin (PCT) were directly correlated with the degree of neutropenia and inverselycorrelated with total leucocyte count (TLC). Conclusions It was highlighted from this study that antibiotics are not necessary for viral infections that have been diagnosed to stop the development of secondary bacterial infections. A clinician should be aware of "when not to use antibiotics,"or the world will soon have to deal with superbugs.

Population pharmacokinetic/pharmacodynamic models of JNJ-64794964, a toll-like receptor 7 agonist, in healthy adult participants.

JNJ-4964 is a TLR7 agonist, which, via a type I interferon (IFN)-dependent mechanism, may enhance host immunity suppressed by persistent exposure to hepatitis B antigens in chronic hepatitis B. PK and PD data were pooled from 2 studies involving 90 participants (n = 74 JNJ-4964, dose range 0.2-1.8 mg; n = 16 placebo) in a fasted state. Food effects on PK were studied in 24 participants (1.2 or 1.25mg). A population PK model and PK/PD models were developed to characterize the effect of JNJ-4964 plasma levels on the time course of IFN-α, IFN-γ-inducible protein 10 (IP-10 or CXCL10), IFN-stimulated gene 15 (ISG15), neopterin and lymphocytes following single and weekly dosing in healthy adults. Covariate effects, circadian rhythms and negative feedback were incorporated in the models. A 3-compartment linear PK model with transit absorption adequately described JNJ-4964 PK. Bioavailability was 44.2% in fed state relative to fasted conditions. Indirect response models with maximum effect (Emax) stimulation on production rate constant (kin) described IFN-α, IP-10, ISG15 and neopterin, while a precursor-dependent indirect response model with inhibitory effect described the transient lymphocyte reduction. Emax, EC50 and γ (steepness) estimates varied according to PD markers, with EC50 displaying substantial between-subject variability. Female and Asian race exhibited lower EC50, suggesting higher responsiveness. PK/PD models well characterized the time course of immune system markers in healthy adults. Our results supported sex and race as covariates on JNJ-4964 responsiveness, as well as circadian rhythms and negative feedback as homeostatic mechanisms that are relevant in TLR7-induced type I IFN responses.

Sero-prevalence of hepatitis B infection among antenatal patients at tertiary care hospital - A prospective study

Hepatitis B infection in a neonate leads to chronic forms of the infection in 90% of the cases associated with the high risk of complications. This is due to transplacental transmission of HBV to the neonates. Early intervention can prevent the infection in the neonates or prevent them to succumb to a chronic infection. The present study aims to explore the seroprevalence of the HBsAg in the blood samples from healthy pregnant women patients.: A total of 200 blood samples were collected from pregnant women attending anti-natal clinic at ZMCH Dahod. HbsAg ELISA and rapid antigen test (HEPA CARD) were used to detect the surface antigen of hepatitis B virus.The age wise distribution of hepatitis B infection in pregnant women using HBsAg specific ELISA shows a total prevalence of 5.26% of hepatitis B infection among pregnant women of different age groups. The prevalence of hepatitis B infection among women of age groups 18-27 years to be 4.76%, followed with 6.89% in age group 28-37 years. The present study shows a prevalence range of 4% to 5.26% of hepatitis B infection among antenatal women.

Relation of Hepatitis B Viral Load with Hepatitis B Envelope Antigen in Hepatitis B Positive Cases

Background: Despite of effective vaccineand impressive treatment, number of cases of hepatitis b virus rising dayby day. The reasons include low antibody titre in blood after vaccination, needle stick injury in medical personnel,lack of awareness in general public about the mode of transmissions and prevention. Also the treatment part isexpensive and monitored by repeated viral load and envelope antigen estimation.We are conducted a study todecrease the cost of diagnosis and monitoring of treatment by analyse if anyrelationship between viral load andenvelope antigen.Method: Total number of 54 blood samples of hepatitis b positive patients who were known to be infected the timeof withdrawn of blood, collected in a period of one year.The serums separated by centrifugation and preserved.All samples were tested for viral load by Thermo Fisher PCR kit and also for estimation of hepatitis b envelopeantigen by indirect ELISA. Results were analysed.Conclusion: On the basis of this study we can conclude that there is a relationship between hepatitis b envelopeantigen and viral load. When viral load reached in a patient up to a particular level antigen start rising andthen both proportionally increasing. In our study that particular level of viral loadis &gt;106 copies/ml. It shows ifenvelope antigen of hepatitis b virus present in blood, the value of viral load should be more than 106copies/ml.In the scarcity of PCR only Elisa for envelope antigen can draw an approximate estimation of viral load.

Intrahepatic quantification of HBV antigens in chronic hepatitis B reveals heterogeneity and treatment-mediated reductions in HBV core-positive cells

Patterns of liver HBV antigen expression have been described but not quantified at single-cell resolution. We applied quantitative techniques to liver biopsies from individuals with chronic hepatitis B and evaluated sampling heterogeneity, effects of disease stage, and nucleos(t)ide (NUC) treatment, and correlations between liver and peripheral viral biomarkers. Hepatocytes positive for HBV core and HBsAg were quantified using a novel four-plex immunofluorescence assay and image analysis. Biopsies were analysed from HBeAg-positive (n= 39) and HBeAg-negative (n= 75) participants before and after NUC treatment. To evaluate sampling effects, duplicate biopsies collected at the same time point were compared. Serum or plasma samples were evaluated for levels of HBV DNA, HBsAg, hepatitis B core-related antigen (HBcrAg), and HBV RNA. Diffusely distributed individual HBV core+ cells and foci of HBsAg+ cells were the most common staining patterns. Hepatocytes positive for both HBV core and HBsAg were rare. Paired biopsies revealed large local variation in HBV staining within participants, which was confirmed in a large liver resection. NUC treatment was associated with a >100-fold lower median frequency of HBV core+ cells in HBeAg-positive and HBeAg-negative participants, whereas reductions in HBsAg+ cells were not statistically significant. The frequency of HBV core+ hepatocytes was lower in HBeAg-negative participants than in HBeAg-positive participants at all time points evaluated. Total HBV+ hepatocyte burden correlated with HBcrAg, HBV DNA, and HBV RNA only in baseline HBeAg-positive samples. Reductions in HBV core+ hepatocytes were associated with HBeAg-negative status and NUC treatment. Variation in HBV positivity within individual livers was extensive. Correlations between the liver and the periphery were found only between biomarkers likely indicative of cccDNA (HBV core+ and HBcrAg, HBV DNA, and RNA). HBV infects liver hepatocyte cells, and its genome can exist in two forms that express different sets of viral proteins: a circular genome called cccDNA that can express all viral proteins, including the HBV core and HBsAg proteins, or a linear fragment that inserts into the host genome typically to express HBsAg, but not HBV core. We used new techniques to determine the percentage of hepatocytes expressing the HBV core and HBsAg proteins in a large set of liver biopsies. We find that abundance and patterns of expression differ across patient groups and even within a single liver and that NUC treatment greatly reduces the number of core-expressing hepatocytes.

HBs Antigen Seroprevalence of the Hepatitis B Virus in Blood Donors using Enzyme Linked Immunosorbent Assay at the Essos Hospital Centre of Yaounde, Cameroon

Background: Hepatitis B virus (HBV) is one of the most common infectious pathogens worldwide particularly in sub Saharan African (SSA). In Cameroon, HBV is highly endemic (HBsAg &gt;8%), suggesting a rigorous transfusion safety policy on the national territory. This study aimed to determine HBs antigen (HBsAg) seroprevalence of the HBV in blood donors using Enzyme Linked Immunosorbent (ELISA) at the Essos Hospital Centre (EHC) in Yaounde, Cameroon. Methods: From January, 18th to May 31st, 2021, we carried out a quantitative, cross-sectional and descriptive study among 326 volunteer blood donors attending EHC of Yaounde, Cameroon. The socio-demographic data of the participants was described while the surface antigen of hepatitis B virus (HBsAg) was determined using qualitative ELISA (Rapid Labs HBsAg) technique in the sera or plasma. The data was analyzed using the IBM Statistical Package for the Social Sciences (SPSS) v. 22. The difference between two proportions was considered significant when the probability of error was less than 0.05 (p&lt;0.05). Results: The median age of blood donors was 25 years (min-max: 12-52 years), the male were more represented with 96.32% (314/326) and the sex ratio (M/F) was 26.2. Globally, the HBsAg seroprevalence among blood donors was 13.19% (95% CI: 9.7%-17.4%; 43/326). The seroprevalence of HBV (HBsAg) was not statistically associated with sociodemographic characteristics of the study population (p&lt;0.05). Meanwhile, this seroprevalence was high in male (95.35%; n=41), in the blood donors aged between 18 and 26 years old (51.16%; n=22), in single (83.72%; n=36) in blood donors with secondary education (74.42%; n=32). In addition, informal (55.81%; n=24), catholic (100.0%) and family blood donors (100.0%) were more infected. Conclusion: This study revealed a very high HBs antigen seroprevalence in blood donors attending the EHC in Yaounde, Cameroon. However, none of the sociodemographic characteristics was not significantly associated with HBV infection in the study population. Thus, reducing the frequency of post-transfusion hepatitis B remains a permanent challenge in Cameroon.