HBV Genotype Research Articles

Genetic characterization of hepatitis B virus genotypes among patients with chronic infection in Sulaimaniyah city, Iraq.

Hepatitis B virus (HBV) genotypes are distributed unevenly throughout the world's regions. The researchers' goal in this study was to find out which HBV genotypes are now prevalent in the blood of chronic HBV patients in Iraq's Kurdistan Region's Sulaimaniyah governorate. Genotyping was carried out utilizing Polymerase Chain Reaction (PCR) type-specified primers. Thirty-three chronic HBV patients were included in the HBV genotyping assay. Phylogenic trees of Pre-S1/Pre S2/S genes' nucleotide sequences were constructed using 36 HBV isolates. All the patients had HBV genotype D. Additionally, two samples were further analyzed by sequencing and deposited in GenBank as HBV/Sul-1/2021 accession numbers MZ077051 and HBV/Sul-2/2021 accession numbers MZ077052. Phylogenic analysis indicated that the HBV isolates belong to sub-genotype D1/serotype ayw2. The HBV/Sul-2/2021 had two sequence deletion mutations from G61del-T87del, which accounted for 27 amino acid deletions, and ten other mutations were identified in the carboxylic terminus of the pre-S1 from Q104del-R113del. Accordingly, 37 amino acids were deleted in the S promoter region. Several other substitution mutations were recorded in both HBV isolates. Patients with chronic HBV were found to have the HBV sub-genotype D1/subtype ayw2 with no mixed genotypes. HBV/Sul-1/2022, a new strain with a 37-amino acid mutation, was found to be distinct from any previously known HBV isolates.

HBV genotype-dependent association of HLA variants with the serodecline of HBsAg in chronic hepatitis B patients

Seroclearance of hepatitis B surface antigen (HBsAg) is regarded as the functional cure for chronic hepatitis B (CHB). The relationship between human leukocyte antigen (HLA) variants, hepatitis B virus genotype, and longitudinal HBsAg serodecline remains to be explored. A total of 1735 HBeAg-seronegative CHB patients with genotype B or C infection of the community-based REVEAL-HBV cohort were genotyped for rs1710 (HLA-G) and rs2770 (HLA-B) using TaqMan assay. Cox proportional hazard regression and generalized linear mixed models were used to analyze the association of HLA genetic variants with the rate of HBsAg seroclearance and longitudinal HBsAg serodecline. Rs1710 G allele was differentially associated with the HBsAg seroclearance in genotype B [aRR (95% CI) = 0.74 (0.56–0.98)] and genotype C [aRR (95%CI) = 1.43 (1.08–1.88)] infection. Rs2770 G allele was associated with HBsAg seroclearance only in genotype B infection [aRR (95% CI) = 0.69 (0.52–0.91)]. The alleles associated with HBsAg seroclearance were significant predictors for the serodecline of HBsAg levels in an HBV genotype-dependent manner (genotype B infection: rs1710, P = 0.013; rs2770, P = 0.0081; genotype C infection: rs1710, P = 0.0452). Our results suggest both spontaneous HBsAg seroclearance and serodecline are modified by the interaction between HLA variants and HBV genotype.

Distribution and relevance of hepatitis B genotypes in the general population of Slovakia.

The aim of the presented study was to determine the distribution of HBV genotypes and their influence on selected parameters in patients in eastern Slovakia. The study includes 202 patients with confirmed chronic HBV infection or hepatitis. For each patient, basic demographic data, and serum samples were collected. The degree of liver fibrosis was determined by transient elastography. The obtained data were evaluated statistically. Out of a total of 202 patients, 96.0 % of the patients were from the EU region and 27 patients (13.4 %) self-identified as Roma ethnic group. The most common genotype among our patients was genotype A (n = 104; 51.5 %), followed by genotype D (n = 76; 37.6 %) and A/D (n = 13; 6.4 %). In patients from the EU region, genotypes A and D predominated statistically significantly (p < 0.0001). Due to a low number of patients with other genotypes, in the subsequent analysis, we only compared patients with HBV genotypes A or D. Patients with genotypes D and A/D significantly more often mention tattoos as a possible risk factor for disease transmission compared to patients with genotype A (p = 0.043). Subsequently, we divided patients into two groups - treated and untreated. The level of qHBsAg was significantly higher in untreated patients with genotypes A (p < 0.0001). The influence of HBV genotypes on other laboratory parameters was not confirmed in our study. This is the first HBV genotypes study from Slovakia. We suggest that HBV genotypes may play a role in the virus-host relationship Keywords: chronic hepatitis B, genotypes, hepatitis B virus, prognostic factors, distribution.

Molecular Detection of Hepatitis B Virus Among HBsAg Non-Reactive Blood of Donors

Despite all blood donations being tested routinely for HBsAg as a clinical marker of transmissible HBV, cases of post-transfusion hepatitis B virus infection are still being reported because molecular studies using Polymerase Chain Reaction (PCR) are not routinely available for Transfusion Transmissible Infection (TTIs) testing. In this study, we sought to use the PCR technique to re-screen donated blood that had already been proven to be HBsAg non-reactive with rapid diagnostic testing and ELISA. One hundred and eighty-five samples were obtained from a proportion of the blood deposited at the blood bank of the Federal Medical Center, Birnin-Kebbi, Nigeria. Socio-demographic parameters such as age group, status, ethnicity, occupation, and group PCV were obtained from donors' records. Nested PCR was employed to detect HBV DNA. Furthermore, genotyping was performed to determine HBV genotypes in the positive samples using PCR with genotype-specific primers. Of the 185 donors, it was observed that five (2.7%) of the population were positive for HBV. HBV is more common among people aged 18–30, singles, Hausa, and self-employed. In addition, the five positive samples were of genotype E. This study suggests the need to complement antibody-based tests with DNA testing for effective HBV screening and consequent safe transfusion. Keywords: Hepatitis B Virus; HBsAg; PCR; DNA testing

Phylogeography of hepatitis B virus: The role of Portugal in the early dissemination of HBV worldwide.

In Portugal, the genetic diversity, origin of HBV and the Portuguese role in the dissemination of HBV worldwide were never investigated. In this work, we studied the epidemic history and transmission dynamics of HBV genotypes that are endemic in Portugal. HBV pol gene was sequenced from 130 patients followed in Lisbon. HBV genotype A was the most prevalent (n = 54, 41.5%), followed by D (n = 44, 33.8%), and E (n = 32, 24.6%). Spatio-temporal evolutionary dynamics was reconstructed in BEAST using a Bayesian Markov Chain Monte Carlo method, with a GTR nucleotide substitution model, an uncorrelated lognormal relaxed molecular clock model, a Bayesian skyline plot, and a continuous diffusion model. HBV subgenotype D4 was the first to be introduced in Portugal around 1857 (HPD 95% 1699-1931) followed by D3 and A2 a few decades later. HBV genotype E and subgenotype A1 were introduced in Portugal later, almost simultaneously. Our results indicate a very important role of Portugal in the exportation of subgenotypes D4 and A2 to Brazil and Cape Verde, respectively, in the beginning of the XX century. This work clarifies the epidemiological history of HBV in Portugal and provides new insights in the early and global epidemic history of this virus.

MOLECULAR PREVALENCE OF HEPATITIS B VIRUS (HBV) GENOTYPES IN PESHAWAR

Background and Aim: Globally Hepatitis B is life-threatening problem including in Pakistan with an estimated incidence rate of 3% in the general population. According to recent findings Pakistan has an enormous burden of HBV infection, but very little attention has been drawn in terms of the molecular epidemiology of HBV. Till now HBV has been categorized into 10 genotypes and different genotypes exhibit different pathogenicity and response towards the treatment, so this research study was planned to evaluate the current status of different HBV genotypes prevailing in Peshawar district of Khyber Pakhtunkhwa (KP). Method: A collection of 550 blood samples was carried out from chronically infected HBV- positive patients and tested by ICT that was further confirmed for HBV DNA with qualitative PCR and followed by type-specific PCR to identify the prevalence of specific HBV genotypes. Sequencing was performed on the respective genotype and a phylogenetic study was done using the MEGA 6.0 tool. Results: All samples were diagnosed HBV positive. Genotype D was recorded as the most widely distributed (90%) while 10% were detected positive for genotype C and no other genotype was found in our study in district Peshawar. Phylogenetic analysis of obtained sequences shows close homology with already reported strains of HBV. Conclusion: The only genotype predominant was genotype D in the District Peshawar region which is the most commonly found genotype in Pakistan and the neighboring countries.

Preclinical characterization of ABI-H2158, an HBV core inhibitor with dual mechanisms of action

The HBV core protein plays an integral role in multiple steps of the HBV lifecycle. Consequently, HBV core inhibitors interrupt multiple steps of the replication cycle, including blocking pgRNA encapsidation and prematurely disassembling existing nucleocapsids, thereby preventing them from transporting relaxed circular (rcDNA) to the nucleus for conversion to covalently closed circular DNA (cccDNA). ABI-H2158 is an HBV core inhibitor that advanced into Phase 2 clinical trials for the treatment of chronic hepatitis B virus infection (cHBV) but was discontinued due to hepatotoxicity. Here, the potency, selectivity, and mechanisms of action of ABI-H2158 were evaluated using a variety of cell-based assays. Antiviral activity was measured by quantifying intracellular or secreted HBV DNA, RNA, and antigens. ABI-H2158 inhibited HBV replication by blocking pgRNA encapsidation in induced HepAD38 cells (EC50 = 22 nM) and had similar potency in HBV-infected HepG2-NTCP cells (EC50 = 27 nM) and primary human hepatocytes (PHH) (EC50 = 41 nM). ABI-H2158 is a pan-genotypic HBV inhibitor, with EC50s ranging from 7.1 to 22 nM across HBV genotypes A-E. ABI-H2158 also potently blocked the formation of cccDNA in de novo HBV infections with EC50s of ∼200 nM in HepG2-NTCP and PHH assays. These results indicate ABI-H2158 has dual mechanisms of action, inhibiting both early and late steps of the HBV replication cycle.

Synthetic Stimulator of Interferon Genes (STING) Agonists Induce a Cytokine-Mediated Anti-Hepatitis B Virus Response in Nonparenchymal Liver Cells.

Chronic hepatitis B (CHB) remains a major public health problem worldwide, with limited treatment options, but inducing an antiviral response by innate immunity activation may provide a therapeutic alternative. We assessed the cytokine-mediated anti-hepatitis B virus (HBV) potential for stimulating the cyclic GMP-AMP synthase-stimulator of interferon genes (STING) pathway using STING agonists in primary human hepatocytes (PHH) and nonparenchymal liver cells (NPCs). The natural STING agonist, 2',3'-cyclic GMP-AMP, the synthetic analogue 3',3'-c-di(2'F,2'dAMP), and its bis(pivaloyloxymethyl) prodrug had strong indirect cytokine-mediated anti-HBV effects in PHH regardless of HBV genotype. Furthermore, STING agonists induced anti-HBV cytokine secretion in vitro, in both human and mouse NPCs, and triggered hepatic T cell activation. Cytokine secretion and lymphocyte activation were equally stimulated in NPCs isolated from control and HBV-persistent mice. Therefore, STING agonists modulate immune activation regardless of HBV persistence, paving the way toward a CHB therapy.

Some HBeAg-negative chronic hepatitis B patients treated with nucleos(t)ide analogue can achieve HBsAg loss after drug withdrawal: stop-to-cure may be coming

Nucleoside/Nucleotide analogues (NAs) are widely used for the antiviral treatment of chronic hepatitis B (CHB), however, it is difficult to achieve serum hepatitis B surface antigen (HBsAg) loss with NAs therapy. In recent years, several prospective trails have reported that HBsAg loss (functional cure or clinical cure) also occurs in a small number of hepatitis B e antigen (HBeAg) negative CHB patients who discontinued long-term treatment with NAs. Accordingly, the "stop-to-cure" strategy is proposed. Although the mechanism has not been fully elucidated, the known factors related to serum HBsAg loss with NAs withdrawal include HBV genotype, duration of NAs treatment, serum HBsAg and HBV RNA levels at end-of-treatment, and ethnic differences. In the review, we discuss the best time to stop NAs therapy, the potential markers for predicting relapse after cessation of NAs and the possible mechanism of "stop-to-cure" in HBeAg-negative CHB patients, and propose some suggestions on the time of retreatment.

Markers of Viral Hepatitis B in Blood–Plasma Samples of the Indigenous Population of the Far North of Russia. HBV Genotypes and HBsAg Subtypes

Markers of Viral Hepatitis B in Blood–Plasma Samples of the Indigenous Population of the Far North of Russia. HBV Genotypes and HBsAg Subtypes

Genetic diversity of HBV in indigenous populations on the border between Brazil and Bolivia.

Hepatitis B is considered an important public health problem worldwide because it is a chronic infection with a risk factor for cirrhosis and cellular hepatocellular carcinoma. In Brazil, the Rondônia State ranks first in the Northern region regarding the number of deaths due to hepatitis B. In the Amazon basin, genotype F is considered specific to the Americas identified in native populations. But few data on HBV genotyping and phylogenetic analysis are available. The objective of this study was to evaluate the genotypes and subgenotypes of the hepatitis B virus in indigenous people chronic carriers residing in cities of Guajará Mirim and Nova Mamoré in state of Rondônia/Brazil, on the border with Bolivia. A fragment of 417 bp (S gene) was amplified by PCR and submitted to nucleotide sequencing. The genotypes and subgenotypes of the HBV strains were determined through phylogenetic inference using genomic sequences from 197 representatives of the genotypes (A-H). Of the 41 chronic hepatitis B patients enrolled in this study, 27 were HBV-DNA positive. Of the 27 DNA-HBV positives, 39% (17/41) had individual HBV infection and 27% (10/41) were coinfected with HDV. The frequency of genotypes was 40.7% (11/27) for genotype D (HBV-D), 33.3% (9/27) for genotype F (HBV-F) and 25.9% (7/27) for genotype A (HBV-A) with circulating subgenotypes F2, F4, D2, D3, A1, and A2. We characterized the genotypes and subgenotypes of HBV circulating among in indigenous in the State of Rondônia shows for the first time the HBV/D genotype whit greater frequency circulating in nativos of state Rondônia. In conclusion, our findings showed a diversity of HBV genotypes, which is also found in other Brazilian geographical regions.

Establishment and Characterization of an HBV Viral Spread and Infectious System following Long-Term Passage of an HBV Clinical Isolate in the Primary Human Hepatocyte and Fibroblast Coculture System.

The existing cell culture-based methods to study hepatitis B virus (HBV) have limitations and do not allow for viral long-term passage. The aim of this study was to develop a robust in vitro long-term viral passage system with optimized cell culture conditions and a viral isolate with the ability to spread and passage. An HBV genotype A clinical isolate was subjected to multiple rounds of UV treatment and passaged in an optimized primary human hepatocyte (PHH)/human fibroblast coculture system. The passaged UV-treated virus was sequenced and further characterized. In addition, a panel of mutant viruses containing different combinations of mutations observed in this virus was investigated. The clinical isolate was passaged for 20 rounds with 21 days per round in an optimized PHH/human fibroblast coculture system while subject to UV mutagenesis. This passaged UV-mutated isolate harbored four mutations: G225A (sR24K) in the S gene, A2062T in the core gene, and two mutations G1764A and C1766T (xV131I) in the basal core promoter (BCP) region. In vitro characterization of the four mutations suggested that the two BCP mutations G1764A and C1766T contributed to the increased viral replication and viral infectivity. A robust in vitro long-term HBV viral passage system has been established by passaging a UV-treated clinical isolate in an optimized PHH/fibroblast coculture system. The two BCP mutations played a key role in the virus's ability to passage. This passage system can be used for studying the entire life cycle of HBV and has the potential for in vitro drug-resistance selection upon further optimization. IMPORTANCE The existing cell culture-based methods to study HBV have limitations and do not allow for viral long-term passage. In this study, an HBV genotype A clinical isolate was subjected to multiple rounds of UV treatment and passaged in an optimized PHH/human fibroblast coculture system. This passaged UV-mutated isolate carried four mutations across the HBV genome, and in vitro characterization of the four mutations suggested that the two basal core promoter (BCP) mutations G1764A and C1766T played a key role in the virus's ability to passage. In summary, we have developed a robust in vitro long-term HBV viral passage system by passaging an UV-treated HBV genotype A clinical isolate in an optimized PHH/human fibroblast coculture system. This passage system can be used for studying the entire life cycle of HBV and has the potential for in vitro drug-resistance selection upon further optimization.

Molecular Characteristics of Hepatitis B Virus among Children Vaccinated with HBsAg Positive in Huzhou, China.

Objective: The HBV genotypes and surface gene mutation among children born after universal HBV vaccination program were not been clearly investigated in Huzhou, China. Thus, the present study was to investigate HBV genotypes and surface gene mutation in vaccinated children in this area.&#x0D; Methods: Serum samples were collected from 58 children who were chronic HBV infected in Huzhou. The surface gene of HBV were amplified and direct sequencing. Then, the mutations were analyzed.&#x0D; Results: Fifty-six sample were sequenced successfully. The genotype of HBV was genotype B in 45 children and genotype C in 11 children, respectively. Major serotype was adw (42), followed by adr (11) and ayw (3). Sequence analysis showed that 18 amino acid (AA) substitutions sites in major hydrophilic region (MHR) were identified in children (37.5%, 21/56). Most of the substitutions were associated with vaccine immune escape. The genotypes B had a high mutations frequency in the second loop than genotype C. Of note, eight children with low level anti-HBs were still infected with HBV.&#x0D; Conclusion: The predominant genotype and serotype were B and adw among children in Huzhou. Genotype B, MHR mutations, and low anti-HBs levels might be related to immunization failure, although the large-scare vaccination program remarkably decreased the infection of HBV in children, strengthen immunization is recommend in children with low level anti-HBs.

New design and optimization of an in-house quantitative TaqMan Real-Time PCR-based assay for the detection and monitoring of occult hepatitis B virus (genotype A-J) infection

PurposeHBV DNA quantification is used for individuals with uninterpretable serological tests, occult HBV infections, decreasing the window period of the disease, and treatment follow-up. Although there are commercial qPCR assays, they are expensive. In this study, we developed a highly sensitive quantitative TaqMan Real-Time PCR with an exogenous internal control to quantify HBV DNA in serum/plasma. MethodsA specific primer/probe set was designed for the S conserved region of various HBV genotypes. The primer/probe set was evaluated experimentally and in-silico. An exogenous internal control was included to monitor the effects of inhibitors. The standard plasmid was titrated using three different methods to prepare the seven standards for the assay. The functional characteristics of the in-house assay were evaluated using the standards. Two hundred clinical specimens were also tested. ResultsThe LOD of the in-house assay was 40 IU/mL, and the assay was linear from 3.26Log10 to 9.26Log10 IU/mL. The analytical and clinical sensitivity of the assay was 100% and 92.15%, respectively. The analytical and clinical specificity of the assay was 100% and 98.97%, respectively. The positive and negative predictive values of the assay were determined to be 98.94% and 92.38%, respectively. The highest coefficient of variation of the inter/intra-assay was 5.1%. The accuracy was close to 100% for all standards, and the correlation between the in-house assay and commercial kit AltoStar® PCR Kits 1.5 was remarkable. The results of the clinical samples using the standards titrated using AcroMetrix™ HBV Panel, Artus® HBV RG PCR Kit, and AltoStar® PCR Kits 1.5 were comparable (r ​= ​0.942, 0.951, 0.951). ConclusionsThe results indicate that the in-house assay is highly sensitive and specific, reproducible, and cost-benefit. Thus, it can be used to detect and quantify HBV DNA in research and clinical settings.

Detection of HBV DNA among HBsAg Negative Patients

The persistence of Hepatitis B viral DNA (HBV DNA) in the blood or liver without the presence of detectable HBsAg is called Occult Hepatitis B infection (OBI)). This has become a threat when considering prevention of HBV transmission in our community. The purpose of this study was to determine prevalence as well as the HBV genotype(s) associated with OBI in Ibadan, Nigeria. HBsAg negative, using ELISA techniques, 219 blood samples were included for the study. Nested Polymerase Chain Reaction was used for the detection of HBV DNA in the samples. Data collected was processed using descriptive statistics and Chi square at p = 0.05. The number of male and female participants were 102 (46.6%) and 117 (53.4%) (P = 0.204) respectively. The participants have age range from 1 to 70 years with mean age of 32.1 years (SD =12.7) for females and 33.9years (SD = 12.4) for males. The clinical status of participants ranged from asymptomatic to those presented with acute hepatitis disease. Out of the 219 samples tested, one was positive for HBV DNA giving a prevalence of 0.5%. The positive sample was from a 30 years old female. We were unable to determine the genotype of the isolate due to poor sequence data. There is evidence of circulation of Occult Hepatitis B virus in our community as shown with prevalence of 0.5% OBI in this study. There is need for screening of blood units using Nucleic Acid Testing (NAT) technique to reduce the transmission of the virus through transfusion of infected blood and blood products. There is also need to increase awareness of HBV vaccination among the general population to forestall the danger OBI may pose.

THU309 - Polymorphic analysis of bulevirtide sequence in PreS1 of large HBsAg across HBV genotypes A-H

THU309 - Polymorphic analysis of bulevirtide sequence in PreS1 of large HBsAg across HBV genotypes A-H

THU302 - Bulevirtide is broadly active against all HDV genotypes expressing envelopes from HBV genotypes A-H and a large panel of clinical isolates

THU302 - Bulevirtide is broadly active against all HDV genotypes expressing envelopes from HBV genotypes A-H and a large panel of clinical isolates

Epidemiological distribution of hepatitis B virus genotypes in acute hepatitis B cases in China,2015-2017

Objective: To analyze the genotype distribution of acute hepatitis B virus in China. Methods: A total of six hundred and twenty acute Hepatitis B cases reported to China Information System for Diseases Control and Prevention from 2015 to 2017 were selected. First, the full-length HBV genome was obtained by nested PCR amplification. In addition, the HBV genotype was determined by constructing a phylogeny tree. Finally, using primarydata, HBV genotype distribution was analyzed. Results: A total of 519 (83.71%, 519/620) sequences were obtained genotype of 620 acute hepatitis B cases, including A (0.19%, 1/519), B (27.17%, 141/519), C (62.04%, 322/519), D (9.06%, 47/519), I (0.77%, 4/519) and C/D (0.77%, 4/519); B2(95.03%, 134/141) and C2 (72.67%, 234/322) were the two major subgenotypes. Genotypes were distributed differently in seven regions of China. The proportion of genotype C appeared higher in Northeast China (94.55%, 52/55), North China (93.85%, 61/65), East China (78.87%, 56/71), and South China (58.14%, 50/86). The proportion of genotype B was higher in Central China (58.07%, 36/62) and Southwest China (52.94%, 45/85), the proportion of genotype D was the highest in Northwest China (48.42%, 46/95). A total of 515 cases were classified as serotypes, including 'adr' (57.48%, 296/515), 'adw' (30.87%, 159/515), 'ayr' (0.19%, 1/515), and 'ayw' (11.46%, 59/515). Genotype B was dominated by 'adw' serotype (92.14%, 129/140), genotype C was dominated by 'adr' serotype (91.88%, 294/320),all genotype D were 'ayw' serotype. The genotype of acute hepatitis B was correlated with serotype, 'adw' was dominant in genotype B, 'adr' was dominant in genotype C and 'ayw' was dominant in genotype D.In different gender and age group, there was no statistical significance ingenotype distribution (P>0.05). Conclusions: The genotype of acute hepatitis B in China from 2015 to 2017 was mainly B, C, and D; genotype C was dominant in the Northeast China,North China, East China and South China; B and C were common in Central and Southwest China, and genotype B was dominant. Genotype D was primarily distributed in Northwest China. The genotype of acute hepatitis B was correlated with serotype, 'adw' was dominant in genotype B, 'adr' was dominant in genotype C and 'ayw' was dominant in genotype D. There was no difference in the distribution of acute hepatitis B genotypes among different genders and age groups.

КЛИНИЧЕСКОЕ ТЕЧЕНИЕ И ВЫБОР ПРОТИВОВИРУСНОЙ ТЕРАПИИ ХРОНИЧЕСКОГО ГЕПАТИТА В С УЧЕТОМ МОЛЕКУЛЯРНО-ГЕНЕТИЧЕСКИХ СВОЙСТВ ВОЗБУДИТЕЛЯ

Background. The clinical course of chronic hepatitis B (CHB) as well as the efficacy of its antiviral therapy depend on the genetic properties of the virus. Objective. To study the clinical and laboratory parameters of patients with CHB and their dependence on the molecular genetic properties of HBV in order to optimize the choice of antiviral therapy regimen. Material and methods. The study included 231 patients with CHB. Routine hematological and biochemical tests, serum HBV DNA level, liver fibrosis stage were measured. Phylogenetic analysis of HBV was carried out in 90 patients. Results. HBV DNA level above 2000 IU/ml was found in 68.8% of patients. Phylogenetic analysis revealed the circulation in Gomel region of HBV genotypes D (76.7%) and A (22.2%), genotype C being detected as well. Patients with genotype D had higher levels of aminotransferases and gamma-glutamiltransferase as well as higher liver fibrosis indices (p&lt;0.05) as compared to those with genotype A; no differences in viral load were found. Antiviral treatment is indicated in 66.7% of patients with genotype D, and only in 35% of those with genotype A (p=0.01). Nucleos(t)ide analogues are optimal as initial antiviral therapy for 86.8% of patients with indications for treatment. Conclusions. The determination of HBV viral load and genotype is important for predicting liver disease severity and choosing the optimal antiviral therapy regimen.

Performance of the cobas® HBV RNA automated investigational assay for the detection and quantification of circulating HBV RNA in chronic HBV patients.

The amount of HBV RNA in peripheral blood may reflect HBV covalently closed circular DNA (cccDNA) transcriptional activity within infected hepatocytes. Quantification of circulating HBV RNA (cirB-RNA) is thus a promising biomarker for monitoring antiviral treatment. We evaluated the performance of an automated, prototype quantitative HBV RNA assay for use on the Roche cobas® 6800/8800 systems. The sensitivity, specificity, linearity, and potential interference by HBV DNA of the cobas® HBV RNA assay were assessed using synthetic HBV armored RNA and clinical specimens. cobas® HBV RNA results were linear between 10 and 107 copies/mL in clinical samples of several HBV genotypes, and up to 109 copies/mL with synthetic RNA. Precision and reproducibility were excellent, with standard deviation below 0.15 log10 copies/mL and coefficients of variation below 5% throughout the linear range. The presence of HBV DNA had minimal (<0.3 log10 copies/mL) impact on HBV RNA quantification at DNA:RNA ratios of up to approximately one million. In a panel of 36 untreated patient samples, cirB-RNA concentrations were approximately 200-fold lower than HBV DNA. cirB-RNA was detected in all 13 HBeAg-positive patients (mean 6.0 log10 copies/mL), and in 20 of 23 HBeAg-negative patients (mean of quantifiable samples 2.2 log10 copies/mL). Finally, cirB-RNA was detected in 12 of 20 nucleoside analog-treated patients (mean of quantifiable samples 3.4 log10 copies/mL). The cobas® 6800/8800 investigational HBV RNA assay is a high throughput, sensitive and inclusive assay to evaluate the clinical relevance of cirB-RNA quantification in patients with chronic hepatitis B.