Hepatitis B Virus Surface Antigen Levels Research Articles

A Phase 3, Randomized Trial of Bulevirtide in Chronic Hepatitis D

BackgroundCoinfection with hepatitis D virus (HDV) accelerates the progression of liver disease associated with chronic hepatitis B. Bulevirtide inhibits the entry of HDV into hepatocytes.MethodsIn this ongoing phase 3 trial, patients with chronic hepatitis D, with or without compensated cirrhosis, were randomly assigned, in a 1:1:1 ratio, to receive bulevirtide subcutaneously at 2 mg per day (2-mg group) or 10 mg per day (10-mg group) for 144 weeks or to receive no treatment for 48 weeks followed by bulevirtide subcutaneously at 10 mg per day for 96 weeks (control group). Patients will complete 96 weeks of additional follow-up after the end of treatment. The primary end point was a combined response at week 48 of an undetectable HDV RNA level, or a level that decreased by at least 2 log10 IU per milliliter from baseline, and normalization of the alanine aminotransferase (ALT) level. The key secondary end point was an undetectable HDV RNA level at week 48, in a comparison between the 2-mg group and the 10-mg group.ResultsA total of 49 patients were assigned to the 2-mg group, 50 to the 10-mg group, and 51 to the control group. A primary end-point response occurred in 45% of patients in the 2-mg group, 48% in the 10-mg group, and 2% in the control group (P<0.001 for the comparison of each dose group with the control group). The HDV RNA level at week 48 was undetectable in 12% of patients in the 2-mg group and in 20% in the 10-mg group (P=0.41). The ALT level normalized in 12% of patients in the control group, 51% in the 2-mg group (difference from control, 39 percentage points [95% confidence interval {CI}, 20 to 56]), and 56% in the 10-mg group (difference from control, 44 percentage points [95% CI, 26 to 60]). Loss of hepatitis B virus surface antigen (HBsAg) or an HBsAg level that decreased by at least 1 log10 IU per milliliter did not occur in the bulevirtide groups by week 48. Headache, pruritus, fatigue, eosinophilia, injection-site reactions, upper abdominal pain, arthralgia, and asthenia were more common in the 2-mg and 10-mg groups combined than in the control group. No treatment-related serious adverse events occurred. Dose-dependent increases in bile acid levels were noted in the 2-mg and 10-mg groups.ConclusionsAfter 48 weeks of bulevirtide treatment, HDV RNA and ALT levels were reduced in patients with chronic hepatitis D. (Funded by Gilead Sciences; MYR 301 ClinicalTrials.gov number, NCT03852719.)

Immunomodulatory and Antiviral Therapy Improved Functional Cure Rate in CHB Patients with High HBsAg Level Experienced NA.

A functional cure, or hepatitis B virus (HBV) surface antigen (HBsAg) loss, is difficult to achieve in patients with hepatitis B virus e antigen (HBeAg)-positive chronic hepatitis B. The HBV vaccine and granulocyte-macrophage colony-stimulating factor (GM-CSF) have been reported to help reduce HBsAg levels and promote HBsAg loss. In this prospective randomized trial, we evaluated HBsAg loss in patients receiving pegylated interferon-α2b (PEGIFN-α2b) and tenofovir disoproxil fumarate (TDF), with and without GM-CSF and HBV vaccination. A total of 287 patients with HBeAg positive chronic hepatitis B and seroconversion after nucleot(s)ide analog treatment were assigned randomly to three treatment groups for 48 weeks, TDF alone (control), PEGIFN-α2b + TDF, and PEGIFN-α2b + TDF + GM-CSF + HBV vaccine. The primary endpoints were the proportions of patients with HBsAg loss and seroconversion at 48 and 72 weeks. The cumulative HBsAg loss rates in the control, PEGIFN-α2b + TDF, and PEGIFN-α2b + TDF + GM-CSF + HBV vaccine groups at week 48 were 0.0%, 28.3%, and 41.1%, respectively. The cumulative HBsAg seroconversion rates in these groups at week 48 were 0.0%, 21.7%, and 33.9%, respectively. Multivariate regression analysis showed that GM-CSF use plus HBV vaccination was significantly associated with HBsAg loss (p=0.017) and seroconversion (p=0.030). In patients with HBeAg-positive chronic hepatitis B and seroconversion after nucleot(s)ide analog treatment, immunomodulatory/antiviral treatment regimens effectively improved HBsAg loss, and the regimen including GM-CSF and HBV vaccination was most effective.

Apolipoprotein H induces sex-specific steatohepatitis and gut dysbiosis during chronic hepatitis B infection.

Apolipoprotein H (APOH) is involved in lipid metabolism and functions as an acute-phase protein during hepatitis B virus (HBV) infection. Herein, we explored whether APOH acts on the development of fatty liver upon chronic HBV infection. Serum APOH level was significantly lower in cirrhosis patients than in healthy controls or patients with chronic infection. It showed sex bias, with elevated levels in female patients with chronic infection. Also, serum APOH levels were negatively correlated with HBV surface antigen (HBsAg) but positively correlated with albumin and triglyceride levels. In Invitro HBV infection model, HBV upregulated APOH expression in a non-temporal manner, and HBsAg levels were elevated by silencing APOH. RNA sequencing (RNA-seq) demonstrated bidirectional expression of APOH, which impacted the immunoregulation upon infection or the metabolic regulation in HepG2.2.15 cells. Then, ApoH -/- mice with persistent HBV replication displayed steatohepatitis and gut microbiota dysbiosis with synergistic sex differences. Our study deciphers the roles of APOH in chronic liver diseases.

Hepatitis B Virus Utilizes a Retrograde Trafficking Route via the Trans-Golgi Network to Avoid Lysosomal Degradation

Hepatitis B virus (HBV) infection is difficult to cure owing to the persistence of covalently closed circular viral DNA (cccDNA). We performed single-cell transcriptome analysis of newly established HBV-positive and HBV-negative hepatocellular carcinoma cell lines and found that dedicator of cytokinesis 11 (DOCK11) was crucially involved in HBV persistence. However, the roles of DOCK11 in the HBV lifecycle have not been clarified. The cccDNA levels were measured by Southern blotting and real-time detection polymerase chain reaction in various hepatocytes including PXB cells by using an HBV-infected model. The retrograde trafficking route of HBV capsid was investigated by super-resolution microscopy, proximity ligation assay, and time-lapse analysis. The downstream molecules of DOCK11 and underlying mechanism were examined by liquid chromatography-tandem mass spectrometry, immunoblotting, and enzyme-linked immunosorbent assay. The cccDNA levels were strongly increased by DOCK11 overexpression and repressed by DOCK11 suppression. Interestingly, DOCK11 functionally associated with retrograde trafficking proteins in the trans-Golgi network (TGN), Arf-GAP with GTPase domain, ankyrin repeat, and pleckstrin homology domain-containing protein 2 (AGAP2), and ADP-ribosylation factor 1 (ARF1), together with HBV capsid, to open an alternative retrograde trafficking route for HBV from early endosomes (EEs) to the TGN and then to the endoplasmic reticulum (ER), thereby avoiding lysosomal degradation. Clinically, DOCK11 levels in liver biopsies from patients with chronic hepatitis B were significantly reduced by entecavir treatment, and this reduction correlated with HBV surface antigen levels. HBV uses a retrograde trafficking route via EEs-TGN-ER for infection that is facilitated by DOCK11 and serves to maintain cccDNA. Therefore, DOCK11 is a potential therapeutic target to prevent persistent HBV infection.

Hepatocyte-targeted delivery of imiquimod reduces hepatitis B virus surface antigen.

Hepatitis B virus (HBV) can rapidly replicate in the hepatocytes after transmission, leading to chronic hepatitis, liver cirrhosis and eventually hepatocellular carcinoma. Interferon-α (IFN-α) is included in the standard treatment for chronic hepatitis B (CHB). However, this therapy causes serious side effects. Delivering IFN-α selectively to the liver may enhance its efficacy and safety. Imiquimod (IMQ), a Toll-Like Receptor (TLR) 7 agonist, stimulates the release of IFN-α that exhibits potent antiviral activity. However, the poor solubility and tissue selectivity of IMQ limits its clinical use. Here, we demonstrated the use of lipid-based nanoparticles (LNPs) to deliver IMQ and increase the production of IFN-α in the liver. We encapsulated IMQ in two liver-targeted LNP formulations: phospholipid-free small unilamellar vesicles (PFSUVs) and DSPG-liposomes targeting the hepatocytes and the Kupffer cells, respectively. In vitro drug release/retention, in vivo pharmacokinetics, intrahepatic distribution, IFN-α production, and suppression of serum HBV surface antigen (HBsAg) were evaluated and compared for these two formulations. PFSUVs provided >95% encapsulation efficiency for IMQ at a drug-to-lipid ratio (D/L) of 1/20 (w/w) and displayed stable drug retention in the presence of serum. DSPG-IMQ showed 79% encapsulation of IMQ at 1/20 (D/L) and exhibited ∼30% burst release when incubated with serum. Within the liver, PFSUVs showed high selectivity for the hepatocytes while DSPG-liposomes targeted the Kupffer cells. Finally, in an experimental HBV mouse model, PFSUVs significantly reduced serum levels of HBsAg by 12-, 6.3- and 2.2-fold compared to the control, IFN-α, and DSPG-IMQ groups, respectively. The results suggest that the hepatocyte-targeted PFSUVs loaded with IMQ exhibit significant potential for enhancing therapy of CHB.

Effects of hepatitis B vaccination on hepatitis B surface antigen in neonates and its change in vivo.

Vaccination is effective to prevent hepatitis B virus (HBV) infection. However, there is still a risk of infection after vaccination. In clinical work, we found that newborns were positive for HBV surface antigen (HBsAg) after vaccination. To determine the effect of hepatitis B vaccination on the detection of HBsAg trend in newborns. We collected data at birth, history of vaccination for hepatitis B, quantitative HBsAg results, and other information about newborns born in our hospital from July 2017 to July 2020. Serum samples from healthy neonates were randomly selected to be supplemented with recombinant hepatitis B vaccine on a concentration gradient, and HBsAg was measured quantitatively. Data from 1417 neonates were included in the study; 306 (21.6%) were HBsAg positive within 8 d after vaccination, with levels ranging from 0.104 IU/mL to 0.339 IU/mL. The proportion of neonates with HBsAg-positive serum was significantly correlated with the level of hepatitis B surface antibodies (anti-HBs) in the serum of their mothers (P < 0.01). Experiments in vitro showed that the proportion of neonates with HBsAg-positive serum was correlated with the dose of the hepatitis B vaccine, and when the concentration of the hepatitis B vaccine reached 5 ng/mL and 10 ng/mL, the serum HBsAg levels showed a significant negative correlation with the original concentration of serum anti-HBs. Hepatitis B vaccination can affect the level of HBsAg detected in neonatal serum, and the effect could be mitigated by delaying the measurement. Moreover, maternal anti-HBs offset the effects of neonatal vaccination on HBsAg serum levels.

Integrated hepatitis B virus DNA maintains surface antigen production during antiviral treatment.

The focus of hepatitis B functional cure, defined as sustained loss of hepatitis B virus (HBV) surface antigen (HBsAg) and HBV DNA from blood, is on eliminating or silencing the intranuclear template for HBV replication, covalently closed circular DNA (cccDNA). However, HBsAg also derives from HBV DNA integrated into the host genome (iDNA). Little is known about the contribution of iDNA to circulating HBsAg with current therapeutics. We applied a multiplex droplet digital PCR assay to demonstrate that iDNA is responsible for maintaining HBsAg quantities in some individuals. Using paired bulk liver tissue from 16 HIV/HBV-coinfected persons on nucleos(t)ide analog (NUC) therapy, we demonstrate that people with larger HBsAg declines between biopsies derive HBsAg from cccDNA, whereas people with stable HBsAg levels derive predominantly from iDNA. We applied our assay to individual hepatocytes in paired tissues from 3 people and demonstrated that the individual with significant HBsAg decline had a commensurate loss of infected cells with transcriptionally active cccDNA, while individuals without HBsAg decline had stable or increasing numbers of cells producing HBsAg from iDNA. We demonstrate that while NUC therapy may be effective at controlling cccDNA replication and transcription, innovative treatments are required to address iDNA transcription that sustains HBsAg production.

Targeting lipid biosynthesis pathways for hepatitis B virus cure.

Chronic hepatitis B virus (HBV) infection is characterized by the presence of high circulating levels of non-infectious lipoprotein-like HBV surface antigen (HBsAg) particles thought to contribute to chronic immune dysfunction in patients. Lipid and metabolomic analysis of humanized livers from immunodeficient chimeric mice (uPA/SCID) revealed that HBV infection dysregulates several lipid metabolic pathways. Small molecule inhibitors of lipid biosynthetic pathway enzymes acetyl-CoA carboxylase (ACC), fatty acid synthase, and subtilisin kexin isozyme-1/site-1 protease in HBV-infected HepG2-NTCP cells demonstrated potent and selective reduction of extracellular HBsAg. However, a liver-targeted ACC inhibitor did not show antiviral activity in HBV-infected liver chimeric mice, despite evidence of on-target engagement. Our study suggests that while HBsAg production may be dependent on hepatic de novo lipogenesis in vitro, this may be overcome by extrahepatic sources (such as lipolysis or diet) in vivo. Thus, a combination of agents targeting more than one lipid metabolic pathway may be necessary to reduce HBsAg levels in patients with chronic HBV infection.

Liver Disease Screening and Hepatitis C Virus Elimination in Taiwan Rural Indigenous Townships: Village-By-Village Screening and Linking to Outreach Hepatology Care.

Medical resources are limited for hepatitis C virus (HCV) elimination in rural indigenous areas of Taiwan. This study aimed to investigate liver disease risk and conduct a HCV elimination program in two rural indigenous townships. A program of village-by-village screening tests was conducted including hepatitis B virus surface antigen (HBsAg), antibody to HCV (anti-HCV) and gamma-glutamyl transferase (GGT), linking to outreach hepatology care at two indigenous townships (Laiyi and Mudan). Adult residents were invited to join this program. One hepatology specialist assessed liver disease risk, provided HCV treatment counselling and initiated direct acting antivirals (DAA) at an outreach hepatology clinic in primary health centers. A total of 3503 residents attended this program with a screening coverage of 73.5%. The prevalence of HBsAg, anti-HCV, and high GGT level was 8.2%, 10.0% and 19.5%, respectively. Laiyi had significantly higher prevalence of anti-HCV than Mudan. While males had significantly higher prevalence of HBsAg and high GGT in both townships, females in Laiyi had higher anti-HCV prevalence. HBsAg and high GGT prevalence peaked at 40–59 years of age and anti-HCV prevalence increased significantly with age. Two hundred and sixty-three residents visited the outreach hepatology clinic for HCV treatment evaluation, with 121 (46%) residents having active HCV, while 116 received DAA, with 111 (95.7%) achieving HCV elimination. For rural indigenous townships in southern Taiwan, HCV infection and alcohol consumption were two major liver disease risks. While HCV infection was predominant in old females, chronic hepatitis B virus infection and habitual alcohol consumptions predominated in middle-aged males. HCV elimination was achieved by the village-by-village screening model and linked to outreach hepatology care.

Follow-Up of 108 Patients with Chronic Hepatitis B Virus Infection Treated with Polyethylene Glycol-Conjugated Derivatives of Interferon-Alpha and Monitoring of Off-Treatment Virological Relapse.

BackgroundThis single center study, which enrolled 108 patients with chronic hepatitis B virus infection treated with pegylated interferon-alpha (PEG-IFN-α), aimed to follow up and monitor off-treatment responses, including virological relapse, and analyze predictors of long-term efficacy of the PEG-IFN-α regimen.Material/MethodsIn total, 108 hepatitis B e antigen (HBeAg)-positive patients with chronic hepatitis B who had completed the PEG-IFN-α regimen and achieved virological suppression were enrolled. The patients were followed up for 5 years to monitor off-treatment responses. Twenty-eight relevant factors, including the history of antiviral therapy and HBeAg seroconversion, were analyzed using the Cox proportional hazards regression model.ResultsThe cumulative rates of virological suppression were 75.70%, 68.68%, 65.25%, 63.91%, and 63.91% at 1, 2, 3, 4, and 5 years of the follow-up period, respectively. Compared with the rates of virological suppression, the cumulative rates of clinical suppression were 88.41%, 79.83%, 78.59%, 75.65%, and 75.65%, respectively, for the 5 years. Alanine aminotransferase (ALT) normalization at 24 weeks after off-therapy (relative risk [RR]=3.430, P=0.013) was a potential predictor for sustained virological suppression, and the history of anti-viral therapy (RR=0.164, P=0.004), quantitative value of hepatitis B virus surface antigen (HBsAg) at 48 weeks of anti-viral therapy (RR=2.697, P=0.039), and ALT normalization at 24 weeks after off-therapy (RR=5.467, P=0.004) were potential predictors for sustained clinical suppression.ConclusionsOur results suggested that increased HBsAg levels at 48 weeks and normalization of ALT at 24 weeks after off-therapy might be predictive factors for long-term treatment efficacy.

Molecular and Serological Characterization of Hepatitis B Virus (HBV)-Positive Samples with Very Low or Undetectable Levels of HBV Surface Antigen.

Background: Gaps remain in the detection of nucleic acid test (NAT) yield and occult hepatitis B virus (HBV) infection (OBI) by current HBV surface antigen (HBsAg) assays. The lack of detection may be due to HBsAg levels below current assay detection limits, mutations affecting HBsAg assays or HBsAg levels, or the masking of HBsAg by antibody to HBsAg (anti-HBs). In this study, we evaluate the incremental detection of NAT yield and OBI from five diverse geographic areas by an improved sensitivity HBsAg assay and characterize the samples relative to the viral load, anti-HBs status, and PreS1–S2–S mutations. Included is a comparison population with HBV DNA levels comparable to OBI, but with readily detectable HBsAg (High Surface–Low DNA, HSLD). Methods: A total of 347 samples collected from the USA, South Africa, Spain, Cameroon, Vietnam, and Cote D’Ivoire representing NAT yield (HBsAg(−), antibody to HBV core antigen (anti-HBc)(−), HBV DNA(+), N = 131), OBI (HBsAg(−), anti-HBc(+), HBV DNA(+), N = 188), and HSLD (HBsAg(+), anti-HBc(+), HBV DNA(+), N = 28) were tested with ARCHITECT HBsAg NEXT (HBsAgNx) (sensitivity 0.005 IU/mL). The sequencing of the PreS1–S2–S genes from a subset of 177 samples was performed to determine the genotype and assess amino acid variability, particularly in anti-HBs(+) samples. Results: HBsAgNx detected 44/131 (33.6%) NAT yield and 42/188 (22.3%) OBI samples. Mean HBV DNA levels for NAT yield and OBI samples were lower in HBsAgNx(−) (50.3 and 25.9 IU/mL) than in HBsAgNx(+) samples (384.1 and 139.5 IU/mL). Anti-HBs ≥ 10 mIU/mL was present in 28.6% HBsAgNx(+) and 45.2% HBsAgNx(−) OBI, and in 3.6% HSLD samples. The genotypes were A1, A2, B, C, D, E, F, and H. There was no significant difference between HBsAgNx(−) and HBsAgNx(+) in the proportion of samples harboring substitutions or in the mean number of substitutions per sample in PreS1, PreS2, or S for the NAT yield or OBI (p range: 0.1231 to >0.9999). A total of 21/27 (77.8%) of HBsAgNx(+) OBI carried S escape mutations, insertions, or stop codons. HSLD had more PreS1 and fewer S substitutions compared to both HBsAgNx(−) and HBsAgNx(+) OBI. Mutations/deletions associated with impaired HBsAg secretion were observed in the OBI group. Conclusions: HBsAgNx provides the improved detection of NAT yield and OBI samples. Samples that remain undetected by HBsAgNx have exceptionally low HBsAg levels below the assay detection limit, likely due to low viremia or the suppression of HBsAg expression by host and viral factors.

GATA binding protein 4 promotes the expression and transcription of hepatitis B virus by facilitating hepatocyte nuclear factor 4 alpha in vitro

BackgroundGATA binding protein 4 (GATA4) has been reported as a potential target of gene therapy for hepatocellular carcinoma (HCC). It is well known that the main cause of HCC is the chronic infection of hepatitis B virus (HBV). However, whether the effect of GATA4 on HBV has not yet been reported.MethodsIn this study, the regulation of GATA4 on HBV was analyzed in vitro. In turn, the effect of HBV on GATA4 was also observed in vitro, in vivo, and clinical HCC patients. Subsequently, we analyzed whether the effect of GATA4 on HBV was related to hepatocyte nuclear factor 4 alpha (HNF4α) in vitro.ResultsThe results showed that GATA4 significantly promoted the secretion of HBV surface antigen (HBsAg) and HBV e antigen in the cell culture medium, improved the replication of HBV genomic DNA, and increased the level of HBV 3.5 kb pre-genomic RNA and HBV total RNA (P < 0.05). Moreover, it was showed that HBV had no significant effect on GATA4 in vitro and in vivo (P > 0.05). At the same time, GATA4 expression was decreased in 78.9% (15/19) of HCC patients regardless of the HBV and HBsAg status. Among them, there were 76.9% (10/13) in HBV-associated patients with HCC (HBV-HCC), and 83.3% (5/6) in non-HBV-HCC patients. In addition, the expression of HNF4α was also up-regulated or down-regulated accordingly when stimulating or interfering with the expression of GATA4. Furthermore, stimulating the expression of HNF4α could only alleviate the HBsAg level and HBV transcription levels, but had no significant effect on GATA4.ConclusionsIn summary, this study found that GATA4 has a positive effect on HBV, and the potential pathway may be related to another transcription factor HNF4α that regulates HBV.

Hepatoselective Dihydroquinolizinone Bis-acids for HBsAg mRNA Degradation.

Chronic hepatitis B (CHB) is characterized by high levels of hepatitis B virus (HBV) surface antigen (HBsAg) in blood circulation. A major goal of CHB interventions is reducing or eliminating this antigenemia; however, there are currently no approved methods that can do this. A novel family of compounds with a dihydroquinolizinone (DHQ) scaffold has been shown to reduce circulating levels of HBsAg in animals, representing a first for a small molecule. Reductions of HBsAg were a result of the compound's effect on HBsAg mRNA levels. However, commercial development by Roche of a DHQ lead compound, RG-7834, was stopped due to undisclosed toxicity issues. Herein we report our effort to convert the systemic RG7834 compound to a hepatoselective DHQ analog to limit its distribution to the bloodstream and thus to other body tissues.

A210 DECLINE IN HEPATITIS B QUANTITATIVE SURFACE ANTIGEN LEVELS IN CHRONIC HEPATITIS B PATIENTS ON TREATMENT WITH NUCLEOS(T)IDE ANALOGUES

Abstract Background The Hepatitis B virus (HBV) affects over 250 million people worldwide and can lead to cirrhosis and hepatocellular carcinoma. HBV surface antigen (HBsAg) quantification is increasingly used to predict disease activity and treatment response. As there is no virologic cure, clinicians are seeking a “functional cure”, or HBsAg loss, as a guide to safely stopping nucleos(t)ide analogue therapy. Tenofovir Disoproxil Fumarate (TDF) and Entecavir (ETV) are first line therapy but require prolonged treatment to achieve HBsAg clearance. Aims To assess the association between nucleos(t)ide therapy and decline in quantitative HBsAg (qHBsAg) in patients with HBV from Calgary, Alberta. Methods A retrospective review of adult patients with chronic HBV, followed at the University of Calgary Liver Clinic, was conducted between January 2012 and October 2020. Patients were excluded if treatment was discontinued or changed, only had a single qHBsAg measurement, or were co-infected with hepatitis C virus, hepatitis delta virus, or HIV. Patients were stratified according to therapy with TDF, ETV, or no treatment. To identify associations between mean changes in qHBsAg by medication exposure, one-way ANOVAs and t-tests were performed. Results were reported as means and 95% confidence intervals (CI). The median time from initial qHBsAg to most-recent was calculated. Results 187 patients were included in the final analysis (Table 1). 77 were excluded for being on more than one medication over the study period, 10 were excluded due to discontinuation of treatment, and 195 were excluded for single qHBsAg measurements. The mean qHBsAg decline was -750.04 IU/mL (95% CI -1311.58, -188.50) in the TDF group (n=45) and -309.20 IU/mL (95% CI -600.90, -17.50) in the ETV group (n=35) (p=0.20). In the no treatment group (n=107), the mean qHBsAg increased by 711.29 IU/mL (95% CI -600.78, 2023.80)(Figure 1). The median time from initial qHBsAg to most-recent was 980 days. Conclusions Quantitative HBsAg levels declined in patients on TDF and ETV, but increased in untreated patients. Although HBsAg levels showed a trend for greater decline in TDF-treated patients, results failed to reach statistical significance, and may be affected by overall treatment duration. Future studies will explore medication use as a time-varying covariate to identify how change in treatment influences changes in HBsAg over time. Funding Agencies None

Manganese Breaks the Immune Tolerance of HBs-Ag.

BackgroundManganese (Mn2+) has been shown to promote type I interferon (IFN) production and activate the cyclic GMP-AMP synthase (cGAS)/Stimulator of Interferon Genes (STING) signaling pathway, suggesting that Mn2+ could be used as an adjuvant for vaccination. MethodsIn present study, the effects of Mn2+ on vaccination against hepatitis B virus (HBV) were evaluated. We treated mouse hepatocytes and kuppfer cells with Mn2+ with or without adeno-associated virus (AAV)–HBV infection. Expression of IFN-α and IFN-β and activation of TBK1 and IRF3 were monitored. Wild-type and STING-/- mice were treated with Mn2+ and then infected with AAV-HBV. Serum levels of HBV surface antigen (HBsAg), alanine aminotransferase (ALT) activity, IFN-α, and IFN-β were detected. Lymphocyte infiltration in the liver was evaluated. HBsAg-Tg mice were vaccinated with Mn2+ and HBsAg. The serum levels of HBsAg antibody, alanine transaminase activity, and IFN-β were monitored after vaccination. ResultsMn2+ promoted IFN-α and IFN-β production in mouse hepatocytes and kuppfer cells. Mn2+ failed to promote IFN-α and IFN-β production in kuppfer cells deficient in STING. Mn2+ promoted activation/phosphorylation of TBK1 and IRF3 during AAV-HBV infection. Mn2+ decreased serum levels of HBsAG, increased serum levels of alanine aminotransferase (ALT), IFN-α and IFN-β, and enhanced lymphocyte infiltration and the percentage of IFN-γ-producing CD8+ T cells in the liver of AAV-HBV-infected mice. In contrast, Mn2+ treatment did not affect serum levels of HBsAG, ALT, IFN-α, or IFN-β in STING-deficient mice. ConclusionsMn2+ promoted HBsAG antibody, ALT, and IFN-β production after HBsAG immunization. Mn2+ promoted type I IFN production in AAV-HBV infection and HBsAG immunization and could be used as an adjuvant for vaccination.

1055. Assessing the Impact of the Routine Childhood Hepatitis B Immunization and the Need for Hepatitis B Vaccine Birth Dose in Sierra Leone, 2018

BackgroundAll African countries recommend 3 doses of hepatitis B vaccine (HepB3), most at 6, 10, and 14 weeks of age, but few recommend a HepB birth dose (HepB-BD). To evaluate the role of mother to child transmission (MTCT) of hepatitis B virus (HBV) with the 3 dose HepB schedule, we conducted a serosurvey in Sierra Leone among 4–30 month old children and their mothers, and 5–9 year old children.MethodsWe conducted a multi-stage cluster survey in 3 districts. Enumeration areas (EA) were selected by probability proportional to size, followed by random selection of eligible households to identify 1901 children per age group. We tested all participants for HBV surface antigen (HBsAg) by rapid test and collected children’s HepB vaccination history. Serum from all HBsAg+ mothers and 1 HBsAg- mother per EA was tested for total antibodies to HBV core antigen (anti-HBc), HBsAg, HBV e antigen (HBeAg), and HBV DNA. We assessed the association of HBsAg prevalence with HepB vaccination and maternal HBV markers.ResultsAmong 1889 children aged 4–30 months, 20 (1.3%; 95% CI:0.8%–2.0%) were HBsAg+; HepB3 coverage was 85%. Among 2025 children aged 5–9 years, 32 (1.6%; 95% CI:1.1%–2.3%) were HBsAg+; HepB3 coverage was 77%. Of HBsAg+ children, 70% (14/20) of younger and 56% (18/32) of older children received HepB3. Among 1776 mothers of younger children, 169 (9.8%; 95% CI:8.1%–11.7%) were HBsAg+. HBsAg prevalence for children with HBsAg+ mothers was 5.9% (10/169) and 0.7% (6/1605) for those with HBsAg- mothers (adjusted OR=10.6 [95% CI:2.8–40.8]). Of 139 HBsAg+ mothers, 13 (9%) were HBeAg+ and 126 (91%) had detectable HBV DNA. Maternal HBsAg (p=0.026), HBeAg (p< 0.001), and HBV DNA levels ≥ 200,000 IU/mL (p< 0.001) were associated with HBsAg positivity in younger children (Table 1).Table 1: Association of maternal HBV serological and molecular markers with HBsAg positivity in 4–30-month old children — Sierra Leone hepatitis B serosurvey, 2018 ConclusionHBsAg prevalence was much lower among children than among mothers, for whom HepB would not have been available, indicating that routine infant HepB vaccination has substantially lowered HBV burden. Increasing HepB3 coverage could further reduce HBsAg prevalence among children. As HBsAg positivity in young children was strongly associated with having a mother with active HBV infection and > 50% of HBsAg+ children received HepB3, HepB-BD is needed to prevent MTCT of HBV and chronic HBV infections in children.Disclosures All Authors: No reported disclosures

Upconverting nanoparticle reporter\u2013based highly sensitive rapid lateral flow immunoassay for hepatitis B virus surface antigen

Detection of hepatitis B Virus surface antigen (HBsAg) is an established method for diagnosing both acute and chronic hepatitis B virus (HBV) infection. In addition to enzyme immunoassays (EIAs), rapid diagnostic tests (RDTs) are available for the detection of HBsAg in resource-poor settings. However, the available RDTs have inadequate sensitivity and therefore are not suitable for diagnosis of patients with low levels of HBsAg and for blood screening. To provide a high-sensitivity RDT, we developed a lateral flow immunoassay (LFIA) for HBsAg utilizing upconverting nanoparticle (UCNP) reporter. The UCNP-LFIA can use whole blood, serum, or plasma and the results can be read in 30 min using a reader device. When compared with a commercial conventional visually read LFIA, the developed UCNP-LFIA had a Limit of Detection (LoD) of 0.1 IU HBsAg/ml in spiked serum, whereas the LoD of the conventional LFIA was 3.2 IU HBsAg/ml. The developed UCNP-LFIA fulfills the WHO criterion for blood screening (LoD ≤ 0.13 IU HBsAg/ml) in terms of LoD. The UCNP-LFIA and conventional LFIA were evaluated with well-characterized sample panels. The UCNP-LFIA detected 20/24 HBsAg-positive samples within the HBsAg Performance Panel and 8/10 samples within the Mixed Titer Performance Panel, whereas the conventional LFIA detected 8/24 and 4/10 samples in these panels, respectively. The performance of the assays was further evaluated with HBsAg-positive (n = 108) and HBsAg-negative (n = 315) patient samples. In comparison with a central laboratory test, UCNP-LFIA showed 95.4% (95% CI: 89.5–98.5%) sensitivity whereas sensitivity of the conventional LFIA was 87.7% (95%CI: 79.9–93.3%).

Cre/LoxP-HBV plasmids generating recombinant covalently closed circular DNA genome upon transfection

New therapies against hepatitis B virus (HBV) require the elimination of covalently closed circular DNA (cccDNA), the episomal HBV genome. HBV plasmids containing an overlength 1.3-mer genome and bacterial backbone (pHBV1.3) are used in many different models, but do not replicate the unique features of cccDNA. Since the stable cccDNA pool is a barrier to HBV eradication in patients, we developed a recombinant circular HBV genome (rcccDNA) to mimic the cccDNA using Cre/LoxP technology. We validated four LoxP insertion sites into the HBV genome using hydrodynamic tail vein injection into murine liver, demonstrating high levels of HBV surface antigen (HBsAg) and HBV DNA expression with rcccDNA formation. HBsAg expression from rcccDNA was >30,000 ng/mL over 78 days, while HBsAg-expression from pHBV1.3 plasmid DNA declined from 2753 ng/mL to 131 ng/mL over that time in immunodeficient mice (P < 0.001), reflective of plasmid DNA silencing. We then cloned Cre-recombinase in cis on the LoxP-HBV plasmids, achieving plasmid stability in bacteria with intron insertion into Cre and demonstrating rcccDNA formation after transfection in vitro and in vivo. These cis-Cre/LoxP-HBV plasmids were then used to create HBx-mutant and GFP reporter plasmids to further probe cccDNA biology and antiviral strategies against cccDNA. Overall, we believe these auto-generating rcccDNA plasmids will be of great value to model cccDNA for testing new therapies against HBV infection.

Honey Bee Dry Venom Reduces Hepatitis B Virus Surface Antigen Secretion in PLC/PRF/5 Cell Line

Background and Aims: Currently, many efforts are directed toward functional Hepatitis B virus (HBV) treatment. This is achievable by suppression of HBV surface antigen (HBsAg) secretion. In this regard, use of natural products has been the areas of interest by scientific communities. Materials and Methods: Dried Honey Bee venom was extracted for assessing its anti-HBsAg secretion potential. Hepatoma cell-derived PLC/PRF/5 was propagated in complete medium. The cell line was treated by a serial dilution of Bee venom. Cell cytotoxicity (IC50) was measured by MTT colorimetric assay at three post-treatment times. HBsAg secretion was evaluated from PLC/PRF/5 supernatant treated by under-cytotoxic concentrations of Bee venom by using enzyme-linked immunosorbent assay. Results: The results indicated that dried Bee venom extract is able to reduce secretion of HBsAg from the cell line with Selectivity Index (SI) of eight. Reduced levels of HBsAg were in dose-dependent manner and it was in its lower concentrations at 8 ppm after 12 hr post treatment. The IC50 was observed to be 63.78 ppm. Conclusions: The Bee venom has anti-HBV activity. The way we used under-cytotoxic concentration of Bee venom, the HBsAg secretion was restored after 24 hr post treatment. Furthermore, mechanism of action of Bee venom in reducing HBsAg level needs to be further investigated.

Protective immunity against hepatitis B virus infection in a group of vaccinated Sri Lankan military service men following a complete course of vaccination.

Vaccination is the appropriate measure to protect military personnel against the hepatitis B virus (HBV) infection. Testing the military personnel for anti-HBs levels after vaccination is vital in re-vaccinating those that have not developed protective immunity. The aim of the current study was to determine the immunity in a group of vaccinated Sri Lankan military personnel (n = 150; age = 26-44years) following a complete course of hepatitis B virus surface antigen (HBsAg) vaccination by assessing the antibodies against HBsAg (anti-HBs) levels. Three months after the last dose of the vaccination, blood samples were collected from the study population and tested for anti-HBs levels using a commercially available ELISA. Of the 150 military service men tested, 139 (92.67%) had anti-HBs levels higher than 10mIU/mL, WHO approved levels for protective immunity against HBV infection. Of the 139 that had sufficient anti-HBs levels, 24% (36/150) had anti-HBs levels between 10 and 100mIU/mL and 68.67% (103/150) had anti-HBs levels > 100mIU/mL. Overall, 7.33% (11/150) participants had anti-HBs levels < 10mIU/mL. Sero-conversion to > 10mIU/mL anti-HBs was more than 90% in those that were less than 40years of age and it was less than 90% in those that were more than 40years of age.