Development of a quantitative real-time detection assay for hepatitis B virus DNA and comparison with two commercial assays

Synthesis and evaluation of highly potent HBV capsid assembly modulators (CAMs)

Chronic hepatitis B virus (HBV) infection remains a major global health burden. It affects more than 290 million individuals worldwide and is responsible for approximately 900,000 deaths annually. Anti-HBV treatment with a nucleoside analog in combination with pegylated interferon are considered first-line therapy for patients with chronic HBV infection and liver inflammation. However, because cure rates are low, most patients will require lifetime treatment. HBV Capsid Assembly Modulators (CAMs) have emerged as a promising new class of compounds as they can affect levels of HBV covalently closed-circular DNA (cccDNA) associated with viral persistence. SAR studies around the core structure of lead HBV CAM GLP-26 (Fig. 1B) was performed and led to the discovery of non-toxic compound 10a displaying sub-nanomolar anti-HBV activity. Advanced toxicity and cellular pharmacology profiles of compounds 10a were also established and the results are discussed herein.

Characterization of hepatitis B viral forms from patient plasma using velocity gradient: Evidence for an excess of capsids in fractions enriched in Dane particles

Hepatitis B virus (HBV) morphogenesis is characterized by a large over-production of subviral particles and recently described new forms in parallel of complete viral particles (VP). This study was designed to depict circulating viral forms in HBV infected patient plasmas, using velocity gradients and most sensitive viral markers. Plasmas from chronic hepatitis B (CHB) patients, HBeAg positive or negative, genotype D or E, were fractionated on velocity and equilibrium gradients with or without detergent treatment. Antigenic and molecular markers were measured in plasma and in each collected fraction. Fast Nycodenz velocity gradients revealed good reproducibility and provided additional information to standard equilibrium sucrose gradients. HBV-RNAs circulated as enveloped particles in all plasmas, except one, and at lesser concentrations than VP. Calculations based on standardized measurements and relative virion and subviral particle molecular stoichiometry allowed to refine the experimental approach. For the HBeAg-positive plasma, VP were accompanied by an overproduction of enveloped capsids, either containing HBs, likely corresponding to empty virions, or for the main part, devoid of this viral envelope protein. Similarly, in the HBeAg-negative sample, HBs enveloped capsids, likely corresponding to empty virions, were detected and the presence of enveloped capsids devoid of HBs protein was suspected but not clearly evidenced due to the presence of contaminating high-density subviral particles. While HBeAg largely influences HBcrAg measurement and accounts for two-thirds of HBcrAg reactivity in HBeAg-positive patients, it remains a 10 times more sensitive marker than HBsAg to characterize VP containing fractions. Using Nycodenz velocity gradients and standardized biomarkers, our study proposes a detailed characterization of circulating viral forms in chronically HBV infected patients. We provide evidence for an excess of capsids in fractions enriched in Dane particles, likely due to the presence of empty virions but also by capsids enveloped by an HBs free lipid layer. Identification of this new circulating viral particle sets the basis for studies around the potential role of these entities in hepatitis B pathogeny and their physiological regulation.

Discovery and structure activity relationship of glyoxamide derivatives as anti-hepatitis B virus agents

Chronic hepatitis B viral infection is a significant health problem world-wide, and currently available antiviral agents suppress HBV infections, but rarely cure this disease. It is presumed that antiviral agents that target the viral nuclear reservoir of transcriptionally active cccDNA may eliminate HBV infection. Through a series of chemical optimization, we identified a new series of glyoxamide derivatives affecting HBV nucleocapsid formation and cccDNA maintenance at low nanomolar levels. Among all the compounds synthesized, GLP-26 displays a major effect on HBV DNA, HBeAg secretion and cccDNA amplification. In addition, GLP-26 shows a promising pre-clinical profile and long-term effect on viral loads in a humanized mouse model.

Simple Detection of Hepatitis B Virus in Using Loop-Mediated Isothermal Amplification Method

INTRODUCTION

US Military and civilian personnel regularly deploy to regions that are endemic for the Hepatitis B virus (HBV), including the Western Pacific, Africa, Eastern Mediterranean, Southeast Asia, and Europe. When patients have life-threatening injuries that require any blood component that is not immediately available, they are typically transfused with locally collected fresh whole blood from a walking blood bank. Currently, there is no simple and easy method for sensitively screening fresh blood in deployed theaters of conflict.

MATERIALS AND METHODS

In order to fill the gap, we have developed a loop-mediated isothermal amplification (LAMP) assay to detect the presence of HBV in blood products. The primers were designed to target the gene of the pre-Surface/Surface antigen region of HBV. The amplification reaction mixture was incubated at 60°C for 60 min. The amplicon can be detected by a handheld fluorescence tube scanner or an immune-chromatography test strip.

RESULTS

We were able to detect down to 10 copies of viral DNA by LAMP reaction for HBV DNA extracted from HBV-positive plasma. We also identified the optimal heat treatment condition (125°C for 10 min) for plasma specimens without requiring DNA extraction for the LAMP assay. The sensitivity of the assay was evaluated with polymerase chain reaction (PCR) confirmed HBV-positive samples. Using LAMP, we detected HBV in 107 out of 127 (84%) samples.

CONCLUSION

This LAMP assay has the potential to be used in resource-limited settings to improve the safety of locally collected blood in endemic regions.

Comparison of two real-time polymerase chain reaction assays for the detection of severe acute respiratory syndrome-CoV-2 from combined nasopharyngeal-throat swabs

CONTEXT

In the absence of effective treatment or vaccine, the current strategy for the prevention of further transmission of severe acute respiratory syndrome (SARS) CoV-2 (COVID-19) infection is early diagnosis and isolation of cases. The diagnosis of SARS-CoV-2 is done by detecting viral RNA in the nasopharyngeal and throat swabs by real-time polymerase chain reaction (PCR). Many commercial assays are now available for performing the PCR assay.

AIMS

The aim was to evaluate the performance of the SD Biosensor nCoV real-time detection kit with the real-time PCR kit provided by the Indian Council of Medical Research-National Institute of Virology (ICMR-NIV), Pune (NIV Protocol).

SUBJECTS AND METHODS

A total of 253 pairs of nasopharyngeal-oropharyngeal swabs combined in a single viral transport medium were tested for viral RNA by both the protocols. The sensitivity and specificity of the SD Biosensor were calculated considering the ICMR-NIV kit as the gold standard. Matched pairs of recorded cycle threshold values (Ct values) were compared by Pearson's correlation coefficient.

RESULTS

Concordant COVID-19 negative and positive PCR results were reported for 113 and 77 samples, respectively. The SD Biosensor kit additionally detected 62 cases, which were found negative by the NIV protocol. In all discordant positive results by the SD Biosensor kit, the average Ct values were higher than the concordant positive results. A total of forty samples tested positive for E gene by SD Biosensor and having Ct values <25 had 100% concordance with NIV protocol results and 39 samples tested positive for E gene by SD Biosensor having Ct value >32 were all found negative by the NIV protocol.

CONCLUSIONS

The results highlight the need for careful evaluation of commercial kits before being deployed for screening of COVID-19 infections.

Novel Hepatitis B Virus Capsid Assembly Modulator Induces Potent Antiviral Responses In Vitro and in Humanized Mice

Hepatitis B virus (HBV) affects an estimated 250 million chronic carriers worldwide. Though several vaccines exist, they are ineffective for those already infected. HBV persists due to the formation of covalently closed circular DNA (cccDNA)-the viral minichromosome-in the nucleus of hepatocytes. Current nucleoside analogs and interferon therapies rarely clear cccDNA, requiring lifelong treatment. Our group identified GLP-26, a novel glyoxamide derivative that alters HBV nucleocapsid assembly and prevents viral DNA replication. GLP-26 exhibited single-digit nanomolar anti-HBV activity, inhibition of HBV e antigen (HBeAg) secretion, and reduced cccDNA amplification, in addition to showing a promising preclinical profile. Strikingly, long term combination treatment with entecavir in a humanized mouse model induced a decrease in viral loads and viral antigens that was sustained for up to 12 weeks after treatment cessation.

Tripartite motif protein 52 (TRIM52) promoted fibrosis in LX-2 cells through PPM1A-mediated Smad2/3 pathway

To investigate the roles of tripartite motif containing 52 (TRIM52) in human hepatic fibrosis in vitro, human hepatic stellate cell line LX-2 cells were transfected with hepatitis B virus (HBV) replicon to establish HBV-induced fibrosis in LX-2 cells, and then treated with small interfering RNA-mediated knockdown of TRIM52 (siTRIM52). LX-2 cells without HBV replicon transfection were treated with lentiviruses-mediated overexpression of TRIM52 and phosphatase magnesium dependent 1A (PPM1A). Fibrosis response of LX-2 cells were assessed by the production of hydroxyproline (Hyp) and collagen I/III, as well as protein levels of α-smooth muscle actin (α-SMA). PPM1A and phosphorylated (p)-Smad2/3 were measured to assess the mechanism. The correlation between TRIM52 and PPM1A was determined using co-immunoprecipitation, and whether and how TRIM52 regulated the degradation of PPM1A were determined by ubiquitination assay. Our data confirmed HBV-induced fibrogenesis of LX-2 cells, as evidenced by significant increase in Hyp and collagen I/III and α-SMA, which was associated with reduction of PPM1A and elevation of transforming growth factor-β (TGF-β), p-Smad2/3, and p-Smad3L. However, those changes induced by HBV were significantly attenuated with additional siTRIM52 treatment. Similar to HBV, overexpression of TRIM52 exerted promoted effect in the fibrosis of LX-2 cells. Interestingly, TRIM52 induced the fibrogenesis of LX-2 cells and the activation of TGF-β/Smad pathway were significantly reversed by PPM1A overexpression. Furthermore, our data confirmed TRIM52 as a deubiquitinase that influenced the accumulation of PPM1A protein, and subsequently regulated the fibrogenesis of LX-2 cells. TRIM52 was a fibrosis promoter in hepatic fibrosis in vitro, likely through PPM1A-mediated TGF-β/Smad pathway.

Distinct dual antiviral mechanism that enhances hepatitis B virus mutagenesis and reduces viral DNA synthesis

Reverse transcriptase (RT) is an essential enzyme for the replication of retroviruses and hepadnaviruses. Current therapies do not eliminate the intracellular viral replication intermediate termed covalently closed circular (ccc) DNA, which has enhanced interest in hepatitis B virus (HBV) reverse transcription and cccDNA formation. The HBV cccDNA is generated as a plasmid-like episome in the host cell nucleus from the protein-linked relaxed circular (rc) DNA genome in incoming virions during HBV replication. The creation of the cccDNA via conversion from rcDNA remains not fully understood. Here, we sought to investigate whether viral mutagens can effect HBV replication. In particular, we investigated whether nucleoside analogs that act as viral mutagens with retroviruses could impact hepadnaviral DNA synthesis. We observed that a viral mutagen (e.g., 5-aza-2'-deoxycytidine, 5-aza-dC or 5-azacytidine, 5-aza-C) severely diminished the ability of a HBV vector to express a reporter gene following virus transfer and infection of target cells. As predicted, the treatment of 5-aza-dC or 5-aza-C elevated the HBV rcDNA mutation frequency, primarily by increasing the frequency of G-to-C transversion mutations. A reduction in rcDNA synthesis was also observed. Intriguingly, the cccDNA nick/gap region transcription was diminished by 5-aza-dC, but did not enhance viral mutagenesis. Taken together, our results demonstrate that viral mutagens can impact HBV reverse transcription, and propose a model in which viral mutagens can induce mutagenesis during rcDNA formation and diminish viral DNA synthesis during both rcDNA formation and the conversion of rcDNA to cccDNA.

Relationship between hepatitis B core-related antigen levels and sustained HBeAg seroconversion in patients treated with nucleo(s)tide analogues

Hepatitis B e antigen (HBeAg) seroconversion experienced during nucleo(s)tide analogue (NUC) therapy is often not sustained. We aimed to study whether hepatitis B core-related antigen (HBcrAg) levels predict sustained HBeAg seroconversion in patients treated with NUCs. We studied HBeAg-positive patients treated with NUCs for at least 6 months. We quantified HBcrAg at baseline and at the time of HBeAg seroconversion and studied the relationship with HBeAg seroconversion and subsequent relapse. HBcrAg was quantified at baseline in 196 patients; levels varied significantly by HBV genotype and correlated with HBsAg, HBV DNA and HBeAg. Baseline HBcrAg levels were lower in patients who achieved HBeAg seroconversion than in those who did not; the unadjusted hazard ratio (HR) was 0.802 (95% CI: 0.656-0.980, P = 0.031); and this association was not sustained in multivariate analysis. HBcrAg remained detectable in all patients at the time of HBeAg seroconversion. Higher HBcrAg at the time of seroconversion was an independent predictor of relapse (adjusted HR: 1.855 (95% CI: 1.099-3.133, P = 0.021), and none of the patients with HBcrAg < 4.90 log U/mL experienced relapse. Baseline HBcrAg is not an independent predictor of HBeAg seroconversion during NUC therapy. HBcrAg remains detectable in patients after HBeAg seroconversion. Patients with lower levels at the time of seroconversion have a higher probability of sustained HBeAg seroconversion.

Performance evaluation of TRUPCR® HBV Real-time PCR assay for Hepatitis B virus DNA quantification in clinical samples: report from a tertiary care liver centre

Quantitative Real-time PCR (qPCR) based Hepatitis B virus (HBV) DNA load estimation is crucial for the initiation of treatment and serves as a strong predictor of liver disease progression in HBV infected individuals. HBV DNA quantification has been ever evolving with the addition of new qPCR based kits on a regular basis. The study was carried with an objective to evaluate the performance characteristics of a commercially available qPCR kit (TRUPCR^®, 3B Black Bio Biotech, India Ltd.) and compare with CE approved qPCR kit (Artus HBV Real-time PCR, Qiagen, Germany). 121 HBV infected patients were prospectively enrolled from July to December 2016. Aliquots of serum samples were tested in parallel by TRUPCR^® and Artus for HBV DNA levels. Genotype D was most predominant genotype in 36.9% (38/121) of patients followed by genotype A in 14.6% (15/121) patients. Median viral load as seen by Artus was log₁₀IU/ml 3.37 (interquartile range log₁₀IU/ml 2.10-10.89) as compared to TRUPCR^® where it was log₁₀IU/ml 3.54 (interquartile range log₁₀IU/ml 2.67-11.52). A very good correlation was seen between the two assays (R² = 0.964) with a concordance rate of 92.6% (112/121). The TRUPCR^® qPCR HBV kit is capable of providing reliable and rapid HBV DNA quantitation and together with its much lower costs, presents itself as a good alternative.

Risk factors for hepatitis B transmission in South Brazil

BACKGROUND

Hepatitis B virus (HBV) infection is a major public health problem in Brazil. Several risk factors are involved in HBV infection and their identification by a rational and essential approach is required to prevent the transmission of this infection in Brazil.

OBJECTIVES

To evaluate risk factors associated with HBV infection in South Brazil.

METHODS

A total of 260 patients with HBV and 260 controls from Caxias do Sul (state of Rio Grande do Sul, Brazil) participated in this study. All participants were given a standard questionnaire to yield the sociodemographic information and to identify HBV risk factors. HBV infection was detected by HBsAg test in all participants.

FINDINGS

HBV infection in these cases was strongly associated with history of a family member HBV-infected, mainly mother [odds ratio (OR) = 4.86; 95% confidence intervals (CI): 1.69-13.91], father (OR = 5.28; 95% CI: 1.58-17.71), and/or siblings (OR = 22.16; 95% CI: 9.39-52.25); sharing personal objects (OR = 1.40; 95% CI: 1.37-2.38); and having history of blood transfusion (OR = 2.05; 95% CI: 1.10-2.84).

CONCLUSIONS

HBV infection was strongly associated with having a family member infected with hepatitis B, sharing personal objects, and having history of blood transfusion.

Interferon-alpha treatment rapidly clears Hepatitis E virus infection in humanized mice

Antiviral treatment options for chronic Hepatitis E Virus (HEV) infections are limited and immunological determinants of viral persistence remain largely unexplored. We studied the antiviral potency of pegylated interferon-α (pegIFNα) against HEV infections in humanized mice and modelled intrahepatic interferon stimulated gene (ISG) responses. Human gene expression levels in humanized mouse livers were analyzed by qPCR and Nanostring. Human CXCL10 was measured in mouse serum. HEV genotype 3 (gt3) infections were cleared from liver and feces within 8 pegIFNα doses in all mice and relapsed after a single pegIFNα injection in only half of treated animals. Rapid viral clearance by pegIFNα was confirmed in HEV gt1, but not in Hepatitis B Virus infected animals. No ISG induction was observed in untreated HEV gt3 and gt1 infected humanized livers compared to control chimeric mice, irrespective of the human hepatocyte donor, viral isolate or HEV infection duration. Human specific ISG transcript levels in mouse liver increased significantly after pegIFNα treatment and induced high circulating human CXCL10 in mouse serum. In conclusion, HEV gt1 and gt3 infections do not elicit innate intrahepatic immune responses and remain highly sensitive to pegIFNα in immunocompromised humanized mice.

Ultrasensitive detection of serum hepatitis B virus by coupling ultrafiltration DNA extraction with real-time PCR

Background

A simple and reliable DNA extraction of hepatitis B virus (HBV) is critical in developing an ultrasensitive detection method for HBV infection. Current commercially available serum Hepatitis B Virus (HBV) DNA extraction methods are time-consuming, expensive and/or require specialized equipment, which hinders wide adoption of clinical laboratories. This study offers a report on an ultrasensitive HBV DNA detection method by coupling serum HBV DNA extraction by ultrafiltration (UF) with real-time PCR (qPCR) detection.

Methods

Serum proteins were precipitated by phenol to release HBV DNA in the supernatant which was then transferred to the UF devices. The resultant DNA concentrate was eluted and released into qPCR pre-mixture. The UF-qPCR assay performance, including recovery rate, linearity, detection sensitivity, precision and diagnostic accuracy that compared to the CAP-CTM V2.0 assay by analyzing batched low viral load clinical samples was evaluated.

Results

The recovery rate of the UF-based HBV DNA extraction method was above 80%. The assay linearity was demonstrated with a slope of 0.95 and R² values of 0.99. Limit-of-detection (LOD) of the UF-qPCR assay was determined to be 12.1IU/ml. The coefficient of variation (CV) of HBV quantitation for high, low and limit titer samples was 2.28%, 5.77% and 25.59%, respectively. Accuracy of the UF-qPCR assay was confirmed with the reference panel, and there was a strong correlation between these two methods (R² = 0.55, p < 0.01).

Conclusions

The UF-qPCR assay is reliable, highly sensitive, affordable and time-saving, and the method can be used for ultrasensitive detection of serum HBV.

A novel hepatitis B virus subgenotype D10 circulating in Ethiopia

Hepatitis B virus (HBV) is genetically highly divergent and classified in ten genotypes and forty subgenotypes in distinct ethno-geographic populations worldwide. Ethiopia is a country with high HBV prevalence; however, little is known about the genetic variability of HBV strains that circulate. Here, we characterize the complete genome of 29 HBV strains originating from five Ethiopian regions, by 454 deep sequencing and Sanger sequencing. Phylogenetically, ten strains were classified as genotype A1 and nineteen as genotype D. Fifteen genotype D strains, provisionally named subgenotype D10, showed a novel distinct cluster supported by high bootstrap value and >4% nucleotide divergence from other known subgenotypes. In addition, the novel D10 strains harboured nine unique amino acid signatures in the surface, polymerase and X genes. Seventy-two per cent of the genotype D strains had the precore premature stop codon G1896A. In addition, 63% genotype A and 33% genotype D strains had the basal core promoter mutations, A1762T/G1764A. Furthermore, four pre-S deletion variants and two recombinants were identified in this study. In conclusion, we identified a novel HBV subgenotype D10 circulating in Ethiopia, underlining the high genetic variability of HBV strains in Africa.

In-house quantitative real-time PCR for the diagnosis of hepatitis B virus and hepatitis C virus infections

The quantification of viral nucleic acids in serum by real-time PCR plays an important role in diagnosing hepatitis B virus and hepatitis C virus infection. In this study, we developed an assay using specific primers and probes to quantify hepatitis B virus DNA or hepatitis C virus RNA in serum from infected patients. For standardization and validation of the assay, an international panel of hepatitis B virus/hepatitis C virus and standard plasmids was used. A correlation coefficient of 0.983 and 0.963 for hepatitis B virus and hepatitis C virus, respectively, was obtained based on cycle threshold values and concentrations of DNA or RNA. The standard curve showed a linear relationship from 19 IU/mL to 1.9 × 10⁹ IU/mL of serum, with a coefficient of determination (r²) of 0.99. In sera from patients infected with hepatitis B virus or hepatitis C virus viral loads (19 IU/mL and 1.9 × 10⁹ IU/mL), we quantified viral loads with a detection limit of 1.9 × 10² IU/mL. The real-time quantitative PCR assay developed in this study provides an ideal system for routine diagnosis and confirmation of indeterminate serological results, especially in immunosuppressed patients.

Molecular epidemiology and genetic diversity of hepatitis B virus in Ethiopia

Although hepatitis B virus (HBV) infection is hyperendemic in Ethiopia and constitutes a major public health problem, little is known about its genetic diversity, genotypes, and circulation. The aim of this study was to determine the molecular epidemiology and genetic diversity of HBV in Ethiopia, using 391 serum samples collected from HBsAg-positive blood donors living in five different geographic regions. The HBV S/pol gene was amplified, sequenced, and HBV genotypes, subgenotypes, serotypes, and major hydrophilic region (MHR) variants were determined. Phylogenetic analysis of 371 samples (95%) revealed the distribution of genotypes A (78%) and D (22%) in Ethiopia. Further phylogenetic analysis identified one subgenotype (A1) within genotype A, and 4 subgenotypes within genotype D (D1; 1.3%, D2; 55%, D4; 2.5%, and D6; 8.8%). Importantly, 24 isolates (30%) of genotype D formed a novel phylogenetic cluster, distinct from any known D subgenotypes, and two A/D recombinants. Analysis of predicted amino-acid sequences within the HBsAg revealed four serotypes: adw2 (79%), ayw1 (3.1%), ayw2 (7.8%), and ayw3 (11.6%). Subsequent examination of sequences showed that 51 HBV isolates (14%) had mutations in the MHR and 8 isolates (2.2%) in the reverse transcriptase known to confer antiviral resistance. This study provides the first description of HBV genetic diversity in Ethiopia with a predominance of subgenotypes A1 and D2, and also identified HBV isolates that could represent a novel subgenotype. Furthermore, a significant prevalence of HBsAg variants in Ethiopian population is revealed.

Usefulness of in-house PCR methods for hepatitis B virus DNA detection

The aim of the present study was to evaluate the performance of three in-house PCR techniques for HBV DNA detection and compare it with commercial quantitative methods to evaluate the usefulness of in-house methods for HBV diagnosis. Three panels of HBsAg reactive sera samples were evaluated: (i) 50 samples were examined using three methods for in-house qualitative PCR and the Cobas Amplicor HBV Monitor Assay; (ii) 87 samples were assayed using in-house semi-nested PCR and the Cobas TaqMan HBV test; (iii) 11 serial samples obtained from 2 HBV-infected individuals were assayed using the Cobas Amplicor HBV test and semi-nested PCR. In panel I, HBV DNA was detected in 44 samples using the Cobas Amplicor HBV test, 42 samples using semi-nested PCR (90% concordance with Cobas Amplicor), 22 samples using PCR for the core gene (63.6% concordance) and 29 samples using single-round PCR for the pre-S/S gene (75% concordance). In panel II, HBV DNA was quantified in 78 of the 87 HBsAg reactive samples using Cobas TaqMan but 52 samples using semi-nested PCR (67.8% concordance). HBV DNA was detected in serial samples until the 17th and 26th week after first donation using in-house semi-nested PCR and the Cobas Amplicor HBV test, respectively. In-house semi-nested PCR presented adequate concordance with commercial methods as an alternative method for HBV molecular diagnosis in low-resource settings.

Suppression of hepatitis B virus DNA accumulation in chronically infected cells using a bacterial CRISPR/Cas RNA-guided DNA endonuclease

Hepatitis B virus (HBV) remains a major human pathogen, with over 240 million individuals suffering from chronic HBV infections. These can persist for decades due to the lack of therapies that can effectively target the stable viral covalently closed circular (ccc) DNA molecules present in infected hepatocytes. Using lentiviral transduction of a bacterial Cas9 gene and single guide RNAs (sgRNAs) specific for HBV, we observed effective inhibition of HBV DNA production in in vitro models of both chronic and de novo HBV infection. Cas9/sgRNA combinations specific for HBV reduced total viral DNA levels by up to ~1000-fold and HBV cccDNA levels by up to ~10-fold and also mutationally inactivated the majority of the residual viral DNA. Together, these data provide proof of principle for the hypothesis that CRISPR/Cas systems have the potential to serve as effective tools for the depletion of the cccDNA pool in chronically HBV infected individuals.

Development of cost-effective real-time PCR test: to detect a wide range of HBV DNA concentrations in the western Amazon region of Brazil

Background

Currently there is a significant risk of infection with hepatitis B virus (HBV) during blood transfusion in high epidemic area. This is due to the pre-seroconversion window period, immunovariant viral strains and the presence of occult HBV infection (OBI). The aim of this study was to develop an in-house real-time PCR-based method, which was both ultra-sensitive and efficient offering an alternative method for nucleic acid testing (NAT).

Methods

A precore fragment with 109 bp was cloned and serial diluted to standard curve construction. The calibration of the HBV - DNA values was performed against OptiQuant® HBV-DNA Quantification Panel, Acrometrix Europe B.V.).

Results

From our in-house plasmid we prepared serial dilutions ranging from 2 × 10³ – 2 × 10⁹ copies/ml. The threshold was adjusted automatically during analysis and the data collected were analyzed by linear regression (r² = 0.99). The limit of detection for the assay with pHBVRO standards was 2000/ml in a total reaction volume of 30 μl. We found a strong correlation between the two methods (r² = 0.9965 and p < 0.0001). The regression line give us the following equation: Log 10 (IU/mL) = 0.9038Log 10 (copies/mL) − 1.0643, suggesting that 1 IU/mL = 15 copies/mL.

Conclusions

Therefore, we can affirm that the qHBVRO PCR can detect HBV DNA in individuals with hepatitis B at any stage of the disease showing high capacity for NAT screening in hepatitis b donors. This results of sensitivity could provide an advance for automation in blood banks and increasing safety of patients who receive blood transfusions.

Hepatitis B virus prevalence, risk factors and genotype distribution in HIV infected patients from West Java, Indonesia

BACKGROUND

Indonesia currently faces both an increasing HIV incidence and a high hepatitis B virus (HBV) burden.

OBJECTIVE

The objective of our study is to examine the prevalence, risk factors, and genotypic distribution of HBV infection among HIV infected patients in West Java, Indonesia.

STUDY DESIGN

A cross sectional study was conducted among a cohort of HIV infected patients in 2008. Demographic and disease related variables were compared between HBV negative and positive patients. Logistic regression was applied to determine risk factors for HBV co-infection. HBV and HIV genotyping was performed in co-infected patients.

RESULTS

Of 636 HIV-infected patients, the rate of HBV co-infection was 7%. The proportion of males was higher in HBV/HIV co-infected patients than in HIV mono-infected patients (93% vs. 72%, P=0.001). A history of injecting drug use (IDU), but not tattooing, was associated with HBV co-infection [P=0.035 OR 2.41 (95% CI 1.06-5.47)]. In the HIV and HBV treatment naive patients, CD4 cells counts <50cells/mm(3), HIV-RNA plasma ≥10,000copies/ml and AST level above normal were more often found in patients with high HBV-DNA levels (≥20,000IU/ml) as compared to those with low HBV DNA (<20.000IU/ml) (P<0.05). As in the general population, B3 was the dominant subtype in HBV co-infected patients.

CONCLUSION

The prevalence of active HBV infection and the genotype distribution among HIV infected individuals is similar to the overall population in Java. However, an increased prevalence was observed in men with a history of IDU, underlining the need for routine HBV screening and monitoring.

Comparison of Hybrid Capture 2 Assay with Real-time-PCR for Detection and Quantitation of Hepatitis B Virus DNA

Background

Both real-time-polymerase chain reaction (PCR) and hybrid capture 2 (HC2) assay can detect and quantify hepatitis B virus (HBV) DNA. However, real-time-PCR can detect a wide range of HBV DNA, while HC2 assay could not detect lower levels of viremia. The present study was designed to detect and quantify HBV DNA by real-time-PCR and HC2 assay and compare the quantitative data of these two assays.

Materials and methods

A cross-sectional study was conducted in between July 2010 and June 2011. A total of 66 serologically diagnosed chronic hepatitis B (CHB) patients were selected for the study. Real-time-PCR and HC2 assay was done to detect HBV DNA. Data were analyzed by statistical Package for the social sciences (SPSS).

Results

Among 66 serologically diagnosed chronic hepatitis B patients 40 (60.61%) patients had detectable and 26 (39.39%) had undetectable HBV DNA by HC2 assay. Concordant results were obtained for 40 (60.61%) out of these 66 patients by real-time-PCR and HC2 assay with mean viral load of 7.06 ± 1.13 log₁₀ copies/ml and 6.95 ± 1.08 log₁₀ copies/ml, respectively. In the remaining 26 patients, HBV DNA was detectable by real-time-PCR in 20 patients (mean HBV DNA level was 3.67 ± 0.72 log₁₀ copies/ml. However, HBV DNA could not be detectable in six cases by the both assays. The study showed strong correlation (r = 0.915) between real-time-PCR and HC2 assay for the detection and quantification of HBV DNA.

Conclusion

HC2 assay may be used as an alternative to real-time-PCR for CHB patients.

How to cite this article: Majid F, Jahan M, Moben AL, Tabassum S. Comparison of Hybrid Capture 2 Assay with Real-time-PCR for Detection and Quantitation of Hepatitis B Virus DNA. Euroasian J Hepato-Gastroenterol 2014;4(1):31-35.

Serum levels of interferon-gamma-inducible protein 10 and response to peginterferon therapy in HBeAg-positive chronic hepatitis B

BACKGROUND & AIMS

Serum levels of interferon-gamma inducible protein 10 (IP-10) are a marker for immune activity, and may predict response to peginterferon (PegIFN) therapy in chronic hepatitis B.

METHODS

IP-10 was measured at baseline and on-treatment week 12 in 210 HBeAg-positive patients treated with PegIFN for 52 weeks. Response to treatment was assessed at 6 months post-treatment and defined as HBeAg loss, combined response (HBeAg loss with HBV DNA <10,000 c/ml) or HBsAg loss.

RESULTS

Median baseline IP-10 levels were 158 pg/ml. Higher baseline IP-10 was associated with more HBV DNA, HBeAg and HBsAg decline from week 4 onwards, and IP-10 was higher in patients who achieved HBeAg loss (p=0.001) and combined response (p=0.052). A combination of high IP-10 (>150 pg/ml) with absence of precore (PC) and core promoter (BCP) mutants strongly predicted combined response and HBsAg loss: 48% of patients with high IP-10 and no detectable mutants achieved a combined response (p<0.001). A minimal non-significant decline from baseline was observed to week 12 (0.015 log pg/ml, p=0.52 compared to baseline), but decline was somewhat more pronounced in patients who achieved HBeAg loss (0.05 logpg/ml, versus an increase of 0.05 in patients without HBeAg loss, p=0.04).

CONCLUSIONS

Higher pre-treatment IP-10 levels are associated with an increased probability of HBeAg loss after PegIFN therapy. A combination of high baseline IP-10 and absence of PC and BCP mutants identified patients with the highest probability of combined response and HBsAg loss. There appears little use for on-treatment quantification of IP-10 for prediction of response to PegIFN.

Precore and core promoter mutants are associated with higher HBeAg seroconversion but low disease remission rates in HBV patients treated with nucleos(t)ide analogues

HBeAg seroconversion in HBV patients is considered an important event. We determined precore (PC) and base core promoter (BCP) mutations in 137 HBeAg-positive nucleos(t)ide analogues (NA) treated patients by INNO-LiPA HBV PreCore assay (Innogenetics). The majority of patients with nongenotype A had PC/BCP mutants present at baseline (P = 0.02). During 29 months of therapy, 45 patients achieved HBeAg seroconversion. Probability of HBeAg seroconversion was higher in patients with PC and/or BCP mutants (P = 0.01). After HBeAg seroconversion, patients with BCP mutants had more HBeAg relapse (P = 0.07), and PC mutants less often achieved HBV DNA < 2000 IU/mL (P = 0.07).

Durable hepatitis B surface antigen decline in hepatitis B e antigen-positive chronic hepatitis B patients treated with pegylated interferon-α2b: relation to response and HBV genotype

BACKGROUND

On-treatment decline of serum hepatitis B surface antigen (HBsAg) may reflect the immunomodulatory effect of pegylated interferon (PEG-IFN) for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB). We compared HBsAg decline across HBV genotypes between combined responders (HBeAg loss and HBV DNA<10,000 copies/ml at week 78), HBeAg responders (HBeAg loss with HBV DNA>10,000 copies/ml) and non-responders.

METHODS

HBsAg was measured at baseline, on-treatment and 6 months post-treatment in 221 HBeAg-positive CHB patients treated with PEG-IFN with or without lamivudine for 52 weeks, and in a representative subgroup of 142 patients at long-term follow-up (LTFU; mean 3.0 years).

RESULTS

On-treatment HBsAg decline significantly varied according to HBV genotype (A and B more than C and D; P<0.001). On-treatment HBsAg decline also differed between patients with a combined response (n=43) and those without (n=178; 3.34 versus 0.69 log IU/ml decline at week 52; P<0.001). Among patients without a combined response, no difference was observed between HBeAg responders (n=41) versus non-responders (n=137). HBsAg decline was sustained in combined responders and progressed to 3.75 log IU/ml at LTFU. Patients with a combined response achieved pronounced HBsAg declines, irrespective of HBV genotype, and those who achieved HBsAg levels <1,000 IU/ml at week 78 had a high probability of a sustained response and HBsAg clearance through LTFU.

CONCLUSIONS

On-treatment HBsAg decline during PEG-IFN therapy for HBeAg-positive CHB depends upon HBV genotype. Patients with a combined response to PEG-IFN achieve a pronounced HBsAg decline, irrespective of HBV genotype, which is sustained through 3 years of off-treatment follow-up.

Identification and treatment of chronic hepatitis B in Chinese migrants: results of a project offering on-site testing in Rotterdam, The Netherlands

BACKGROUND & AIMS

Migrants born in countries where hepatitis B is endemic are a risk group for chronic hepatitis B virus (HBV) infection. Treatment options have improved, but due to the asymptomatic nature of chronic HBV infection, the majority of patients remain unidentified.

METHODS

In 2009, a campaign targeting the Chinese community was held in the city of Rotterdam, The Netherlands. The campaign combined disease awareness activities with free HBV testing at outreach locations. Chronically HBV infected patients were referred to specialist care based on a referral guideline. Before and after the campaign, knowledge of chronic hepatitis B was measured through questionnaires in a convenience sample of the target population (n=285 and n=277).

RESULTS

In a period of 3 months, 13 outreach activities took place and 1090 Chinese migrants were tested for HBV. Forty-nine percent had serological signs of a past or recent HBV infection and 8.5% (n=92) were chronically infected. Thirty-eight percent (n=35) of chronically infected patients were referred for evaluation by a specialist and of these, 15 started antiviral treatment within 1 year of follow-up. Before the campaign, 55% answered correctly to 6 or more out of 10 knowledge items. Knowledge was positively associated with educational level. After the campaign, an increase in knowledge was observed in participants with low levels of education.

CONCLUSIONS

Chinese migrants could be reached with an outreach campaign, and on-site testing was well accepted. A high prevalence of chronic HBV infection was found and referral to specialist care and initiation of treatment was successful.

Protocol for the use of light upon extension real-time PCR for the determination of viral load in HBV infection

Real-time PCR has engendered wide acceptance for quantitation of hepatitis B virus (HBV) DNA in the blood due to its improved rapidity, sensitivity, reproducibility, and reduced contamination. Here we describe a cost-effective and highly sensitive HBV real-time quantitative assay based on the light upon extension real-time PCR platform and a simple and reliable HBV DNA preparation method using silica-coated magnetic beads.

Close monitoring of hepatitis B surface antigen levels helps classify flares during peginterferon therapy and predicts treatment response

Background. Alanine aminotransferase (ALT) flares occur frequently during peginterferon (PEG-IFN) therapy. We related occurrence of flares to presence of precore (PC) and/or basal core promoter (BCP) mutants and studied kinetics of hepatitis B e antigen (HBeAg) and hepatitis B surface antigen (HBsAg) levels during flares.

Methods. Fifty of 214 (23%) patients treated with PEG-IFN ± lamivudine for 52 weeks experienced flares. Flares were host-induced (ALT elevation followed by HBV DNA decline, n = 19), virus-induced (HBV DNA increase with subsequent ALT elevation, n = 17) or indeterminate (n = 14). Presence of wild-type (WT) or non-WT (detectable PC/BCP mutants) was studied by lineprobe assay.

Results. Fifty-eight percent of host-induced flares occurred in WT HBV patients, whereas 94% of virus-induced flares occurred in patients with PC and/or BCP mutants (P = .003). HBsAg loss was only achieved in patients with a host-induced flare, and WT patients with a host-induced flare cleared HBsAg in 64% of cases. Serum HBsAg levels declined after a host-induced flare, whereas virus-induced flares were accompanied by stable or increasing levels of HBsAg. Patients with a host-induced flare achieved a mean HBsAg reduction of 3.24 log IU/mL, compared with 0.25 log IU/mL in virus-induced flares (P < .001). Patients who achieved a decline in HBsAg of >0.5 log IU/mL within 4 weeks after the flare cleared HBsAg in 64% (7 of 11) of cases.

Conclusions. Host-induced flares are associated with WT virus and may result in decline and clearance of HBV DNA, HBeAg, and HBsAg. Monitoring of HBsAg levels during and after flares may help predict a favorable treatment outcome.

A case of acute hepatitis B related to previous gynecological surgery in Japan

A 41-year-old woman became ill with acute hepatitis B after gynecological surgery performed by a surgeon who was hepatitis B surface antigen positive. The surgeon was positive for hepatitis B e antigen, and HBV DNA concentrations in the serum, saliva, and sweat of the surgeon were very high. HBV genotype and partial HBV DNA sequences from the HBV-infected surgeon were identical to those in the HBV-infected patient. Extensive research by the committee including infection control and prevention specialists judged the source of infection to be a surgeon infected with HBV. Transmission of HBV from a healthcare worker to patients who are not immune to HBV can actually happen. This case report illustrates the importance of a stringent policy of a nationwide HBV universal vaccination program.

Evaluation of single and combination therapies with tenofovir disoproxil fumarate and emtricitabine in vitro and in a robust mouse model supporting high levels of hepatitis B virus replication

Next-generation therapies for chronic hepatitis B virus (HBV) infection will involve combinations of established and/or experimental drugs. The current study investigated the in vitro and in vivo efficacy of tenofovir disoproxil fumarate (TDF) and/or emtricitabine [(-)-FTC] alone and in combination therapy for HBV infection utilizing the HepAD38 system (human hepatoblastoma cells transfected with HBV). Cellular pharmacology studies demonstrated increased levels of (-)-FTC triphosphate with coincubation of increasing concentrations of TDF, while (-)-FTC had no effect on intracellular tenofovir (TFV) diphosphate levels. Quantification of extracellular HBV by real-time PCR from hepatocytes demonstrated the anti-HBV activity with TDF, (-)-FTC, and their combination. Combination of (-)-FTC with TDF or TFV (ratio, 1:1) had a weighted average combination index of 0.7 for both combination sets, indicating synergistic antiviral effects. No cytotoxic effects were observed with any regimens. Using an in vivo murine model which develops robust HBV viremia in nude mice subcutaneously injected with HepAD38 cells, TDF (33 to 300 mg/kg of body weight/day) suppressed virus replication for up to 10 days posttreatment. At 300 mg/kg/day, (-)-FTC strongly suppressed virus titers to up to 14 days posttreatment. Combination therapy (33 mg/kg/day each drug) sustained suppression of virus titer/ml serum (<1 log(10) unit from pretreatment levels) at 14 days posttreatment, while single-drug treatments yielded virus titers 1.5 to 2 log units above the initial virus titers. There was no difference in mean alanine aminotransferase values or mean wet tumor weights for any of the groups, suggesting a lack of drug toxicity. TDF-(-)-FTC combination therapy provides more effective HBV suppression than therapy with each drug alone.

Presence of occult HBV, but near absence of active HBV and HCV infections in people infected with HIV in rural South Africa

Human immunodeficiency (HIV), hepatitis B (HBV), and hepatitis C (HCV) viruses are endemic in Sub-Saharan Africa, but data regarding the prevalence of hepatitis co-infections in HIV-positive individuals residing there are limited. The aim of the study was to determine the prevalence of HBV, HCV, and occult HBV (presence of HBV-DNA in the absence of HBsAg) in a rural, South African cohort. The results were compared to various ethnic groups in a Dutch cohort of people infected with HIV. Antiretroviral-naïve individuals with HIV from both a rural South African clinic (n = 258), and a Dutch University hospital (n = 782), were included. Both serological (HBV and HCV) and molecular (occult HBV) assays were performed. Logistic regression analysis was used to define independent predictors of a hepatitis co-infection. HBV and HCV prevalence rates in the South African cohort were exceptionally low (0.4%, 1/242 and 0.8%, 2/242, respectively), compared to those observed in Caucasians (HBV 4.4% and HCV 10.9%) and African immigrants (HBV 8.9% and HCV 4.8%). Conversely, occult HBV was observed in a considerable proportion (10%, 6/60) of South African patients who were anti-HBc-positive but HBsAg-negative. Occult infections were less frequent in Caucasians and Africans in the Dutch cohort (3.2% and 1.4%, respectively). Independent predictors for occult HBV were not identified, but a trend towards more occult HBV at lower CD4 counts was observed. Local HBV/HCV prevalence data are needed to optimize vaccination and antiretroviral treatment strategies. Occult HBV in patients with HIV may be missed regularly when molecular analyses are not available.

Presence of precore and core promoter mutants limits the probability of response to peginterferon in hepatitis B e antigen-positive chronic hepatitis B

Peginterferon (PEG-IFN) treatment of hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) results in HBeAg loss in 30% of patients, but clearance of hepatitis B virus (HBV) DNA and hepatitis B surface antigen (HBsAg) from serum is less often achieved. We investigated whether the presence of precore (PC) and basal core promoter (BCP) mutants before PEG-IFN treatment affects serological and virological response. A total of 214 HBeAg-positive CHB patients treated with PEG-IFN ± lamivudine for 52 weeks in a global randomized trial were classified at baseline as wildtype (WT) or non-WT (detectable mutants at PC/BCP) by line-probe assay. Response was assessed at 6 months posttreatment and through long-term follow-up (LTFU). Mutants were detected in 64% of patients, in varying frequencies across HBV genotypes A through D. Patients with WT had higher baseline HBV DNA, HBeAg, and HBsAg levels than patients with non-WT. Patients with WT were more likely to achieve HBeAg loss with HBV DNA <10,000 copies/mL (response, 34 versus 11%, P < 0.001) and HBsAg clearance (18 versus 2%, P < 0.001) at week 78 than non-WT patients. Among WT patients who achieved HBeAg clearance at week 78, 78% had undetectable HBV DNA and 61% achieved HBsAg clearance at LTFU (versus 26% and 15% in non-WT patients, P < 0.001 for both). The presence of WT virus at baseline was an independent predictor of response (odds ratio [OR] 2.90, 95% confidence interval [CI]: 1.15-7.31, P = 0.023) and HBsAg clearance (OR 5.58, 95% CI: 1.26-24.63, P = 0.013) and patients with non-A genotypes with detectable mutants had a low probability of response.

CONCLUSION

The presence of only WT virus at baseline is a strong predictor of response (HBeAg loss with HBV DNA <10,000 copies/mL) to PEG-IFN for HBeAg-positive CHB. Patients with detectable PC and/or BCP mutants have a lower probability of response and are less optimal candidates for PEG-IFN therapy.

HBV DNA suppression in HBeAg-positive chronic hepatitis B patients treated with peginterferon or placebo

The aim of the present study was to compare the decline of HBV DNA during peginterferon (PEG-IFN) therapy with spontaneous HBV DNA decline in placebo-treated patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B. A total of 136 patients who participated in a randomized trial were treated with PEG-IFN alfa-2b for 52 weeks. These patients were compared with 167 patients who received a placebo for 48 weeks using linear mixed regression analysis. Response was defined as loss of HBeAg at the end of treatment (EOT). Overall, decline of HBV DNA at the EOT was significantly greater in the PEG-IFN group than in the placebo group (mean decline 2.3 log vs. 1.0 log, P < 0.001) and varied according to HBV genotype. Viral suppression was greater in the PEG-IFN group from week 4 throughout the entire treatment period (P < 0.001). The response rate was 32% for the PEG-IFN group and 11% for the placebo group (P < 0.001). Among responders, HBV DNA decline was greater for patients treated with PEG-IFN than with a placebo: the mean difference in HBV DNA decline was 0.7 log (P = 0.001) at 4 weeks and 2 log (P < 0.001) at the EOT. ALT flares (>5 times the upper limit) were associated with a greater HBV DNA decline during PEG-IFN. In conclusion, PEG-IFN therapy resulted in a greater HBV DNA decline in positive HBeAg patients than a placebo. The decline of HBV DNA was greater in patients with HBeAg loss or who exhibited an ALT flare during PEG-IFN than in patients with spontaneous HBeAg loss or flares during placebo therapy.

LNA real-time PCR probe quantification of hepatitis B virus DNA

In the present study, we standardized a TaqMan locked nucleic acid (LNA) real-time polymerase chain reaction (PCR) probe for the accurate quantification and detection of hepatitis B virus (HBV) DNA in serum (plasma), and evaluated its methodology. LNA probe technology had a much better detection performance in HBV DNA than the common TaqMan probe. The assay based on the LNA probe had a wider linear detection range, higher sensitivity, stability and amplification efficiency, and a lower concentration of probes than the TaqMan probe. Among the 15 cases with chronic hepatitis B surface antigen (HBsAg) (+) alone, only 4 cases that were detected by TaqMan real-time PCR were negative; however, the same samples were positive by LNA real-time PCR (p<0.05). A positive correlation between viral load measurements for the 35 samples with HBV-positive DNA was detected in both LNA and TaqMan real-time PCR.

Frequency and clinical outcomes of flares related to nucleos(t)ide analogue therapy in patients with chronic hepatitis B

Flares in chronic hepatitis B are often detrimental but sometimes lead to sustained immune control and disease remission. The aim of this study was to estimate the frequency of hepatitis flares which occur during and/or after cessation of nucleos(t)ide analogue (NA) therapy, and to assess their outcomes. In a single centre cohort study we investigated 227 patients who received a total of 351 NA treatment courses. NA therapy was discontinued after 149 treatment courses. In total, 27 flares were observed during 9779 on-treatment patient-months. The frequency was estimated as 3.2 per 100 person-years (95% CI 2.2-4.7). Lamivudine (LAM)-treated patients demonstrated the highest frequency (4.9/100 person-years, 95% CI 3.2-7.4). Twenty (74%) of 27 on-therapy flares were associated with development of genotypic resistance, which all occurred during LAM therapy. NA withdrawal flares occurred after a median post-treatment follow-up of 3.5 months in 17 (11%) of 149 treatment discontinuations. No flares were observed in patients who switched to another antiviral agent (n = 51). None of the on-therapy and withdrawal flares related to NA therapy were associated with sustained disease remission, and seven flares resulted in decompensated liver disease. In this study, flares related to NA therapy never led to immune control and sustained disease remission, and sometimes resulted in decompensated liver disease.

Real Time-PCR HBV-DNA Analysis: Significance and First Experience in Armed Forces

BACKGROUND

HBV DNA quantitation is used extensively world wide for the diagnosis and monitoring of treatment of Hepatitis B virus (HBV) infection. However, it has still to be popular in India. The aim of this study was to quantitate HBV - DNA by Real time - PCR method in Hepatitis B and in immuno-compromised patients, to compare the results with HBeAg detection and to monitor the response to therapy of chronic Hepatitis B patients to antivirals.

METHODS

Ninety one serum samples of Hepatitis group of patients (all HBsAg positive), 41 samples from immuno-compromised patients (all HBsAg negative) and 49 patients of Chronic Hepatitis B group (all HBsAg positive) were the subjects of this first ever study in Armed Forces. Twenty serum samples from healthy volunteers and non-hepatitis B patients served as negative controls. The amplification detection was carried out in a Rotor-Gene 2000-sequence detector.

RESULTS

Amongst Hepatitis B group, 33% (30/91) of the samples were positive for HBV-DNA and 26% (24/91) of samples were positive for HBeAg. In the immuno-compromised group of patients 14.6% (6/11) of samples were positive for HIV-DNA and 9.7% (4/41) were positive for HBeAg. Of the Chronic Hepatitis B patients on treatment, all (100%) were positive by HBV-DNA, whereas 29/49 (59.2%) were positive by HBeAg before treatment. After treatment with antivirals, 06/49 (12.2%) were positive by both tests and 11/49 (22.5%) were positive only by HBV-DNA. 32/49 (65.3%) patients became negative serologically after therapy.

CONCLUSION

HBeAg status did not necessarily reflect HBV-DNA level in the serum, as 10/91 (11%) in the Hepatitis B group, 2/41 (4.9%) in the immuno compromised group and 20/49 (40.8%) patients in the Chronic Hepatitis B group were positive for HBV-DNA but negative for HBeAg. HBV-DNA was not found to be positive amongst any of the negative controls. Real time - PCR is a sensitive and reproducible assay for HBV-DNA quantitation and may be started in Armed Forces referral centers in the near future.

Quantification of viral DNA and liver enzymes in plasma improves early diagnosis and management of herpes simplex virus hepatitis

Herpes simplex virus (HSV) hepatitis is a rare and potential life-threatening disease. The diagnosis of HSV hepatitis is hampered by its indifferent clinical presentation, which necessitates confirmatory laboratory data to identify HSV in the affected liver. However, liver biopsies are often contraindicated in the context of coagulopathy, are prone to sampling errors and have low sensitivity in mild HSV hepatitis cases. There is an unmet need for less invasive diagnostic tools. The diagnostic and therapeutic value of HSV DNA load and liver enzyme level kinetics was determined in five patients with HSV hepatitis and twenty disease controls with HSV-DNAemia without hepatitis. At time of hospitalization, patients with HSV hepatitis had a higher median (± interquartile range) HSV DNA load (6.0 × 10(6) ± 1.2 × 10(9)) compared to disease controls (171 ± 2845). Viral DNA load correlated with liver transaminase levels and disease severity. Antiviral treatment led to rapid decline of HSV DNA load and improvement of liver function of patients with HSV hepatitis. The data advocate the prompt and consecutive quantification of the HSV DNA load and liver enzyme levels in plasma of patients suspected of HSV hepatitis as well as those under antiviral treatment.

Kinetics of hepatitis B surface antigen differ between treatment with peginterferon and entecavir

BACKGROUND & AIMS

We aimed to investigate serum hepatitis B surface antigen (HBsAg) levels in patients with chronic hepatitis B virus (HBV) infection during peginterferon (PEG-IFN) and entecavir (ETV) monotherapy.

METHODS

HBsAg was quantified (Abbott ARCHITECT) at baseline and during antiviral therapy (weeks 12, 24, 36, 48) in hepatitis B e antigen (HBeAg-) positive patients treated with ETV (n=33) or PEG-IFN (n=61) and in HBeAg-negative patients treated with ETV (n=37) or PEG-IFN (n=69).

RESULTS

Within the HBeAg-positive population, patients treated with PEG-IFN tended to have a steeper HBsAg decline than ETV-treated patients (mean decline 0.94 versus 0.38 log IU/ml at week 48, p=0.07 for comparison of the slope of HBsAg decline). The HBsAg decline was larger in those patients who became HBeAg negative, irrespective of the treatment regimen. A decline in HBsAg was confined to ETV-treated patients with elevated baseline alanine aminotransferase (ALT) levels, whereas HBsAg decline was not associated with baseline ALT in patients treated with PEG-IFN. Within the HBeAg-negative population, PEG-IFN induced a significant HBsAg decline, while HBsAg did not decrease in ETV-treated patients (0.56 versus -0.10 log IU/ml, p<0.001). Both in HBeAg-positive and HBeAg-negative patients, the decline in serum HBV DNA was larger in patients who received ETV as compared to patients treated with PEG-IFN.

CONCLUSIONS

In HBeAg-positive patients, the decline in serum HBsAg is mainly confined to patients who clear HBeAg, by either PEG-IFN or ETV treatment. In HBeAg-negative patients, PEG-IFN therapy resulted in a significant reduction in HBsAg levels, whereas HBsAg did not decrease in ETV-treated patients.

Molecular methods in the diagnosis and management of chronic hepatitis B

Chronic hepatitis B (CHB) infection remains a major global problem but the recent advances in molecular methods have revolutionized the diagnosis and management of CHB. Hepatitis B virus (HBV) DNA quantitation is the most useful molecular marker for the diagnosis and management of CHB. There is increasing evidence that the clinical outcome and efficacy of antiviral therapy for CHB could vary with the infecting HBV genotype, core promoter and precore mutations. Early identification of drug resistance is imperative in the management of CHB. The molecular methods for HBV DNA quantitation, HBV genotyping, the identification of mutants, genotypic and phenotypic methods for monitoring drug resistance and their utility and limitations for use in the diagnosis and monitoring of CHB are discussed in this article.

Long-term therapy with tenofovir is effective for patients co-infected with human immunodeficiency virus and hepatitis B virus

BACKGROUND & AIMS

We investigated the long-term efficacy and renal safety of tenofovir disoproxil fumarate (TDF), administered to patients co-infected with human immunodeficiency virus and hepatitis B virus (HBV) as part of an antiretroviral therapy.

METHODS

We performed a multicenter, prospective cohort study of 102 patients co-infected with human immunodeficiency virus and HBV who were treated with TDF.

RESULTS

At baseline, 80% of patients had a detectable viral load (HBV DNA >20 IU/mL). Among patients positive for hepatitis B e antigen (HBeAg) (n = 67), 92% had a virologic response (HBV DNA <20 IU/mL) after 5 years of treatment. There was no difference between patients with or without lamivudine resistance at baseline (P = .39). Loss rates of HBeAg and hepatitis B s antigen (HBsAg) were 46% and 12%, respectively. Among HBeAg-negative patients (n = 15), 100% had a virologic response after 4 years of treatment and 2 (13%) lost HBsAg. Twenty subjects (20%, all HBeAg-negative) had undetectable HBV DNA at baseline; during a median follow-up period of 52 months (interquartile range, 41-63 mo), 19 (95%) maintained a virologic response and 2 (10%) lost HBsAg. Overall, one patient acquired a combination of resistance mutations for anti-HBV drugs and experienced a virologic breakthrough. Three (3%) patients discontinued TDF because of increased serum creatinine levels. The estimated decrease in renal function after 5 years of TDF therapy was 9.8 mL/min/1.73 m(2), which was most pronounced shortly after TDF therapy was initiated.

CONCLUSIONS

TDF, administered as part of antiretroviral therapy, is a potent anti-HBV agent with a good resistance profile throughout 5 years of therapy. Only small nonprogressive decreases in renal function were observed.

The "original" hepatitis B virus of Eastern chimpanzees (Pan trogrodytes schweinfurthii)

Little is known about Hepatitis B Virus (HBV) infections in chimpanzees. Therefore, we investigated the prevalence of chimpanzee HBV (chHBV) infections in captive, wild born chimpanzees in the sanctuary on Ngamba Island, Uganda and one sample from a wild free ranging chimpanzee. In one third of the plasma samples (32.4%; 12/37) we detected antibodies to Hepatitis B (core) antigen. Amongst those individuals HBV DNA was detected in one captive wild born and the wild chimpanzee. In contrast to the only available earlier described HBV sequence from the subspecies Pan troglodytes schweinfurthii, there was no evidence of recombination with human HBV. Our sequences therefore are likely to present the "original" chHBV from P. t. schweinfurthii.

A real-time quantitative assay for hepatitis B DNA virus (HBV) developed to detect all HBV genotypes

Hepatitis B virus (HBV) is a major cause of chronic liver disease worldwide. Besides genotype, quantitative analysis of HBV infection is extensively used for monitoring disease progression and treatment. Affordable viral load monitoring is desirable in resource-limited settings and it has been already shown to be useful in developing countries for other viruses such as Hepatitis C virus (HCV) and HIV. In this paper, we describe the validation of a real-time PCR assay for HBV DNA quantification with TaqMan chemistry and MGB probes. Primers and probes were designed using an alignment of sequences from all HBV genotypes in order to equally amplify all of them. The assay is internally controlled and was standardized with an international HBV panel. Its efficacy was evaluated comparing the results with two other methods: Versant HBV DNA Assay 3.0 (bDNA, Siemens, NY, USA) and another real-time PCR from a reference laboratory. Intra-assay and inter-assay reproducibilities were determined and the mean of CV values obtained were 0.12 and 0.09, respectively. The assay was validated with a broad dynamic range and is efficient for amplifying all HBV genotypes, providing a good option to quantify HBV DNA as a routine procedure, with a cheap and reliable protocol.

Prediction of sustained response to peginterferon alfa-2b for hepatitis B e antigen-positive chronic hepatitis B using on-treatment hepatitis B surface antigen decline

Serum hepatitis B surface antigen (HBsAg) levels may reflect the immunomodulatory efficacy of pegylated interferon (PEG-IFN). We investigated within a large randomized trial whether quantitative HBsAg levels predict response to PEG-IFN in patients with hepatitis B e antigen (HBeAg)-positive chronic hepatitis B. Serum HBsAg was measured in samples taken at baseline and weeks 4, 8, 12, 24, 52, and 78 of 221 patients treated with PEG-IFN alfa-2b with or without lamivudine for 52 weeks. HBsAg decline was compared between treatment arms and between responders and nonresponders. Response was defined as HBeAg loss with HBV DNA < 10,000 copies/mL at 26 weeks after treatment (week 78); 43 of 221 (19%) patients achieved a response. One year of PEG-IFN with or without lamivudine resulted in a significant decline in serum HBsAg, which was sustained after treatment (decline 0.9 log IU/mL at week 78, P < 0.001). Patients treated with combination therapy experienced a more pronounced on-treatment decline, but relapsed subsequently. Responders experienced a significantly more pronounced decline in serum HBsAg compared to nonresponders (decline at week 52: 3.3 versus 0.7 log IU/mL, P < 0.001). Patients who achieved no decline at week 12 had a 97% probability of nonresponse through posttreatment follow-up and no chance of HBsAg loss. In a representative subset of 149 patients similar results were found for prediction through long-term (mean 3.0 years) follow-up.

CONCLUSION

PEG-IFN induces a significant decline in serum HBsAg in HBeAg-positive patients. Patients who experience no decline from baseline at week 12 have little chance of achieving a sustained response and no chance of HBsAg loss and should be advised to discontinue therapy with PEG-IFN.