Variability in the precore and core promoter regions of HBV strains in Morocco: characterization and impact on liver disease progression

The role of hepatitis B virus genome variations in HBV-related HCC: effects on host signaling pathways

Hepatocellular carcinoma (HCC) is a significant global health issue, with a high prevalence in many regions. There are variations in the etiology of HCC in different regions, but most cases are due to long-term infection with viral hepatitis. Hepatitis B virus (HBV) is responsible for more than 50% of virus-related HCC, which highlights the importance of HBV in pathogenesis of the disease. The development and progression of HBV-related HCC is a complex multistep process that can involve host, viral, and environmental factors. Several studies have suggested that some HBV genome mutations as well as HBV proteins can dysregulate cell signaling pathways involved in the development of HCC. Furthermore, it seems that the pathogenicity, progression of liver diseases, response to treatment and also viral replication are different among HBV mutants. Understanding the relationship between HBV genome variations and host signaling pathway alteration will improve our understanding of the molecular pathogenesis of HBV-related HCC. Furthermore, investigating commonly dysregulated pathways in HBV-related HCC is necessary to discover more specific therapeutic targets and develop more effective strategies for HCC treatment. The objective of this review is to address the role of HBV in the HCC progression and primarily focus on the impacts of HBV genome variations on HCC-related signaling pathways.

Whole genome analysis of hepatitis B virus before and during long-term therapy in chronic infected patients: Molecular characterization, impact on treatment and liver disease progression

Hepatitis B virus (HBV) infection remains a serious public health concern worldwide despite the availability of an efficient vaccine and the major improvements in antiviral treatments. The aim of the present study is to analyze the mutational profile of the HBV whole genome in ETV non-responder chronic HBV patients, in order to investigate antiviral drug resistance, immune escape, and liver disease progression to Liver Cirrhosis (LC) or Hepatocellular Carcinoma (HCC). Blood samples were collected from five chronic hepatitis B patients. For each patient, two plasma samples were collected, before and during the treatment. Whole genome sequencing was performed using Sanger technology. Phylogenetic analysis comparing the studied sequences with reference ones was used for genotyping. The mutational profile was analyzed by comparison with the reference sequence M32138. Genotyping showed that the studied strains belong to subgenotypes D1, D7, and D8. The mutational analysis showed high genetic variability. In the RT region of the polymerase gene, 28 amino acid (aa) mutations were detected. The most significant mutations were the pattern rtL180M + rtS202G + rtM204V, which confer treatment resistance. In the S gene, 35 mutations were detected namely sP120T, sT126S, sG130R, sY134F, sS193L, sI195M, and sL216stop were previously described to lead to vaccine, immunotherapy, and/or diagnosis escape. In the C gene, 34 mutations were found. In particular, cG1764A, cC1766G/T, cT1768A, and cC1773T in the BCP; cG1896A and cG1899A in the precore region and cT12S, cE64D, cA80T, and cP130Q in the core region were associated with disease progression to LC and/or HCC. Other mutations were associated with viral replication increase including cT1753V, cG1764A/T, cC1766G/T, cT1768A, and cC1788G in the BCP as well as cG1896A and cG1899A in the precore region. In the X gene, 30 aa substitutions were detected, of which substitutions xT36D, xP46S, xA47T, xI88F, xA102V, xI127T, xK130M, xV131I, and xF132Y were previously described to lead to LC and/or HCC disease progression. In conclusion, our results show high genetic variability in the long-term treatment of chronic HBV patients causing several effects. This could contribute to guiding national efforts to optimize relevant HBV treatment management in order to achieve the global hepatitis elimination goal by 2030.

Analysis of hepatic fibrosis markers in the serum of chronic hepatitis B patients according to basal core promoter/precore mutants

The A1762T/G1764A double mutant in the basal core promoter (BCP) region of the hepatitis B virus (HBV) is associated with severe hepatic lesions while the G1899A mutation with the double mutant is associated with a significant reduction in the risk of severe fibrosis. This study aims to measure a number of markers in the serum of patients with chronic HBV infection and to assess relationships between these markers and BCP/precore mutants with consideration of the stage of fibrosis. The serum levels of resistin, TGF-β1, MMP-1, TIMP-1, collagen IA1 and PDGF-BB, which are markers that are known to be involved in the process of hepatic fibrosis, were assayed. The serum levels of PDGF-BB and TIMP-1, and the mutation profile were independently associated with advanced fibrosis. A higher level of TIMP-1 was associated with advanced fibrosis regardless of the mutation status, and a higher level of PDGF-BB was associated with nonsevere fibrosis in patients infected with viruses harboring the A1762T/G1764A or A1762T/G1764A/G1899A mutations. Our results suggest an impact of the A1762T/G1764A mutant on the biological pathway related to TGF-β1 and PDGF-BB. In vitro studies are needed to understand the impact of these mutants on the serum secretion of markers involved in fibrosis severity.

Prevalence of Hepatitis B Virus Infection Markers among Patients of the Ibn Sina University Hospital Center (Rabat, Morocco)

INTRODUCTION

Viral hepatitis B is a global scourge affecting millions of people worldwide. In Morocco, hepatitis B is considered a public health problem, and available data converge to consider Morocco as a country with intermediate endemicity. In the present study, we have planned to evaluate the HBV prevalence in Morocco on a large scale and to assess the prevalence of different serological markers for better management of this infection in Morocco.

METHODS

This study was conducted on 18,877 patients referring to the Ibn Sina University Hospital Center of Rabat, Morocco. HBV serological markers including HBsAg, HBsAb, HBeAg, HBeAb, and total HBcAb were assessed by immune-enzymatic assays. The quantification of HBV DNA was performed by real-time PCR.

RESULTS

The overall prevalence of positive cases for HBsAg, HBsAb, and total HBcAb was 2.47%, 27.66%, and 21.2%, respectively. From 141 patients with an isolated HBcAb serological profile (HBcAb+/HBsAb-/HBsAg-), HBV DNA was detected in 10 patients, representing a rate of 7.09%. In the present study, up to 95.78% of HBV chronic carriers were negative for HBeAg.

CONCLUSION

This study highlights a higher prevalence of HBsAg in the hospital-based population than the general population reported previously in Morocco and a very low HBV immunization coverage. Of particular interest, detectable HBV DNA levels in isolated HBcAb patients show that exclusive HBsAg screening cannot eliminate the risk of HBV transmission in certain cases. Many efforts are then mandatory to promote serological testing and increase the vaccination rate to limit viral dissemination for better management of this disease in Morocco.

Regulation of the Hepatitis B virus replication and gene expression by the multi-functional protein TARDBP

Hepatitis B virus (HBV) infects the liver and is a key risk factor for hepatocellular carcinoma. Identification of host factors that support viral replication is important to understand mechanisms of viral replication and to develop new therapeutic strategies. We identified TARDBP as a host factor that regulates HBV. Silencing or knocking out the protein in HBV infected cells severely impaired the production of viral replicative intermediates, mRNAs, proteins, and virions, whereas ectopic expression of TARDBP rescued production of these products. Mechanistically, we found that the protein binds to the HBV core promoter, as shown by chromatin precipitation as well as mutagenesis and protein-DNA interaction assays. Using LC-MS/MS analysis, we also found that TARDBP binds to a number of other proteins known to support the HBV life cycle, including NPM1, PARP1, Hsp90, HNRNPC, SFPQ, PTBP1, HNRNPK, and PUF60. Interestingly, given its key role as a regulator of RNA splicing, we found that TARDBP has an inhibitory role on pregenomic RNA splicing, which might help the virus to export its non-canonical RNAs from the nucleus without being subjected to unwanted splicing, even though mRNA nuclear export is normally closely tied to RNA splicing. Taken together, our results demonstrate that TARDBP is involved in multiple steps of HBV replication via binding to both HBV DNA and RNA. The protein’s broad interactome suggests that TARDBP may function as part of a RNA-binding scaffold involved in HBV replication and that the interaction between these proteins might be a target for development of anti-HBV drugs.

Analysis of HBV X gene quasispecies characteristics by next-generation sequencing and cloning-based sequencing and its association with hepatocellular carcinoma progression

OBJECTIVES

This study aimed to describe the differences between next-generation sequencing (NGS) and cloning-based sequencing (CBS) in HBX quasispecies research and primitively investigate the relationship between the dominant HBX quasispecies and hepatocellular carcinoma (HCC).

METHODS

A total of 12 serum samples were collected. Serum hepatitis B virus (HBV) DNA was extracted, and the HBV X-region (HBX) was amplified by nested polymerase chain reaction (PCR). The PCR products were simultaneously tested with NGS and CBS to detect quasispecies of the HBX.

RESULTS

A total of 9348 eligible quasispecies sequences were obtained by NGS, which were much larger than the 98 of that by CBS. By the phylogenetic tree, the dominant quasispecies sequence of each sample could be found, although they had several nucleotides differences between the dominant quasispecies sequences found by CBS and NGS. By comparing the quasispecies heterogeneity, it was found that the quasispecies complexity value of HBV X-region obtained by NGS was higher than CBS (P < 0.05). The diversity values, including d, dS, dN, an d d N/ dS obtained by NGS were lower than by CBS (all of P < 0.01). The relativity of Spearman(rs) in d, dS, and dN were statistically significant (rs_ d = 0.865, P = 0.001; rs_ dS = 0.722, P = 0.014; and rs_ dN = 0.738, P = 0.011, respectively). There were 21 different bases between the HBX quasispecies of case A and control B.

CONCLUSION

The results of this can be used as guidance when researchers plan to choose a suitable method to study quasispecies, especially the HBV X gene quasispecies. Some high-risk mutations of HBX quasispecies were also found in this study and their relationship with HCC need deeper exploration.

Hepatitis B virus (HBV) X gene mutations and their association with liver disease progression in HBV-infected patients

Hepatitis B virus (HBV) is one of the most widespread human pathogens causing chronic hepatitis, liver cirrhosis, and hepatocellular carcinoma (HCC). This study investigated the clinical impact of single and combinational mutations in HBx gene on the pathogenesis of HCC during progressive stages of liver disease. The patients were categorized into inactive HBV carriers, active carriers, cirrhosis and HCC groups based on disease severity. Male sex, age > 50 years, and high serum alanine aminotransferase level were associated with risk of progressive liver disease. I127T, V131I, and F132Y/I/R mutations showed a significant increasing trend associated with the disease progression to HCC. H94Y and K130M mutations were also significantly associated with severe liver disease. One double mutation (K130M+V131I) and two triple mutations (I127T+K130M+V131L and K130M+V131I+F132Y) were observed, with significant rising prevalence through progressive clinical phases of liver disease to HCC. Several single and combinational mutations in HBx correlating with severity and progressive clinical phases of HBV infection were identified. The mutational combinations may have a synergistic effect in accelerating the progression to HCC. These specific patterns of HBx mutations can be useful in predicting the clinical outcome of HBV-infected patients and may serve as early markers of high risk of developing HCC.

Different precore/core mutations of hepatitis B interact with, limit, or favor liver fibrosis severity

BACKGROUND AND AIM

The impact of basal core promoter (BCP) and precore (PC) mutants of the hepatitis B virus (HBV) on liver disease severity remains controversial. The aim of the present study was to screen BCP and PC mutations in 252 HBV surface antigen (HBsAg) positive carriers in France and to assess relationships between these mutations and severe fibrosis.

METHODS

Direct sequencing of the precore/core gene was used to detect A1762T/G1764A and G1757A mutations in the BCP and G1896A and G1899A mutations in the PC region.

RESULTS

The prevalences of A1762T/G1764A, G1757A, G1896A, and G1899A mutations were 34.1%, 38.7%, 54.9%, and 29.3% (P < 0.001), respectively. The independent predictors of severe fibrosis (≥F3 Metavir) were older age (P < 0.001), male gender (P = 0.012), elevated alanine aminotransferase (P < 0.001), and the double A1762T/G1764A mutant with no other mutations (P = 0.011). Interestingly, the association of the G1899A mutation with the double A1762T/G1764A mutant significantly counteracted the deleterious effect of the sole double A1762T/G1764A mutant (odds ratio [OR] = 0.28 vs. OR = 3.55, respectively, P = 0.028).

CONCLUSIONS

Patients with the A1762T/G1764A mutation have a higher risk of severe fibrosis. The G1899A mutation is a protective factor against severe fibrosis that counteracted the deleterious effect of the A1762T/G1764A mutation. Finally, host phenotypic and HBV genotypic markers independently predict fibrosis severity.

Mutations in pre-core and basic core promoter regions of hepatitis B virus in chronic hepatitis B patients

AIM: To investigate the frequency of mutations in pre-core (pre-C) and basic core promoter (BCP) regions of hepatitis B virus (HBV) from Shanxi Province, and the association between mutations and disease related indexes.

METHODS: One hundred chronic hepatitis B patients treated at Shanxi Province Hospital of Traditional Chinese Medicine were included in this study. PCR-reverse dot blot hybridization and mismatch amplification mutation assay (MAMA)-PCR were used to detect the mutations in the HBV pre-C and BCP regions. HBV DNA content and liver function were compared between patients with mutant HBV pre-C and BCP loci and those with wild-type loci. The consistency between PCR-reverse dot blot hybridization and MAMA-PCR for detecting mutations in the HBV pre-C and BCP regions was assessed.

RESULTS: Of the 100 serum samples detected, 9.38% had single mutations in the pre-C region, 29.17% had single mutations in the BCP region, 41.67% had mutations in both BCP and pre-C regions, and 19.79% had wild-type loci. The rates of BCP and pre-C mutations were 65.7% and 34.3%, respectively, in hepatitis B e antigen (HBeAg) positive patients, and 84.6% and 96.2%, respectively, in HBeAg negative patients. The rate of pre-C mutations was significantly higher in HBeAg negative patients than in HBeAg positive patients (χ² = 26.62, P = 0.00), but there was no significant difference in the distribution of mutations in the BCP region between HBeAg positive and negative patients (χ² = 2.43, P = 0.12). The presence of mutations in the pre-C (Wilcoxon W = 1802.5, P = 0.00) and BCP regions (Wilcoxon W = 2906.5, P = 0.00) was more common in patients with low HBV DNA content. Both AST and GGT were significantly higher in patients with mutant pre-C and BCP loci than in those with wild-type loci (P < 0.05). PCR-reverse dot blot hybridization and MAMA-PCR for detection of mutations in the BCP and pre-C regions had good consistency, and the Kappa values obtained were 0.91 and 0.58, respectively.

CONCLUSION: HBeAg negative patients tend to have HBV pre-C mutations. However, these mutations do not cause increased DNA copies, but associate with damage of liver function.

G1896A Precore Mutation and Association With HBeAg Status, Genotype and Clinical Status in Patients With Chronic Hepatitis B

BACKGROUND

Precore stop codon (G1896A) mutation is one of the commonest mutations found in patients with chronic hepatitis B. However, over the years, this mutation was not reported much in Malaysia.

OBJECTIVES

We therefore investigated the presence of G1896A mutation in Malaysian population and its association with HBeAg status, clinical stage, hepatitis B virus (HBV) genotype and e-seroconversion rate.

PATIENTS AND METHODS

Serum samples from 93 patients confirmed as hepatitis B carriers were collected for molecular assay. The whole genome of HBV was amplified by polymerase chain reaction and directly sequenced. The precore and basal core promoter regions were analyzed for presence of mutations.

RESULTS

The most commonly observed mutation in the precore region was C1858T with 64.5% prevalence. The precore mutation of interest (G1896A) was identified in 25.8% of isolates. The basal core promoter mutations detected were A1762T-G1764A (26.9%), C1653T (8.6%), A1752G (10.8%) and C1766T (2.2%). No significant association was observed between G1896A mutation and HBeAg-negativity. Nonetheless, G1896A was highly prevalent among HBV genotype B. Clinical association revealed that subjects with G1896A mutations were mainly detected in asymptomatic chronic hepatitis B (58.3%) and liver cirrhosis (41.7%). One subject was diagnosed with fulminant hepatitis (4.2%) and 8.3% had hepatocellular carcinoma (HCC).

CONCLUSIONS

Our data suggested an intermediate prevalence of G1896A mutation among Malaysian hepatitis B carriers. The stop codon mutation has a significant association with genotype B and patients with chronic hepatitis B and liver cirrhosis.

Expression of serum sCD163 in patients with liver diseases and inflammatory disorders

OBJECTIVE

To investigate the diagnostic values of soluble cluster of differentiation 163 (sCD163) in patients with liver failure or various inflammations.

METHODS

Serum samples were collected from patients admitted to the First Affiliated Hospital, Zhejiang University from October 2013 to January 2015 for treatment of with liver diseases, including liver failure (n=38), hepatitis B virus (HBV)-induced liver cancer (HBsAg positive) (n=40), HBV-induced hepatic cirrhosis (HBsAg positive) (n=40), chronic hepatitis B (n=38), HBV carrier (n=40), fatty liver patients without HBV infection (n=40), chronic glomerulonephritis (n=38), community acquired pneumonia (n=38) and acute pancreatitis (n=38). The CD163/sCD163 was determined using commercial ELISA kits according to the manufacturer's instructions.

RESULTS

Significant decrease was noticed in the sCD163 in patients with fatty liver and HBV carrier compared with that of patients with chronic hepatitis B (P < 0.05). Compared with the healthy controls, the level of sCD163 was remarkably increased in the other groups (P < 0.05). The serum sCD163 in patients with HBV-induced liver cancer showed statistical difference compared with those of the patients with fatty liver, HBV carrier, as well as those with liver failure (P < 0.05). The expression of sCD163 was remarkably elevated in patients with liver failure compared with the patients with liver cancer, HBV-induced hepatic cirrhosis, chronic hepatitis B, fatty liver, or HBV carrier (P < 0.05). No significant difference was noticed in the sCD163 in patients with chronic hepatitis B, community acquired pneumonia, chronic glomerulonephritis, and acute pancreatitis (P > 0.05).

CONCLUSIONS

sCD163 is a sensitive marker protein for liver failure. The elevation of sCD163 was closely related to the progression of the liver failure. No statistical difference was noticed in the sCD163 in patients with inflammatory disorders, indicating sCD163 showed no organ specificity.

Genomic Diversity of Hepatitis B Virus Infection Associated With Fulminant Hepatitis B Development

CONTEXT

After five decades of Hepatitis B Virus (HBV) vaccine discovery, HBV is still a major public health problem. Due to the high genetic diversity of HBV and selective pressure of the host immune system, intra-host evolution of this virus in different clinical manifestations is a hot topic of research. HBV infection causes a range of clinical manifestations from acute to chronic infection, cirrhosis and hepatocellular carcinoma. Among all forms of HBV infection manifestations, fulminant hepatitis B infection possesses the highest fatality rate. Almost 1% of the acutely infected patients develop fulminant hepatitis B, in which the mortality rate is around 70%.

EVIDENCE ACQUISITION

All published papers deposited in Genbank, on the topic of fulminant hepatitis were reviewed and their virological aspects were investigated. In this review, we highlight the genomic diversity of HBV reported from patients with fulminant HBV infection.

RESULTS

The most commonly detected diversities affect regulatory motifs of HBV in the core and S region, indicating that these alterations may convert the virus to an aggressive strain. Moreover, mutations at T-cell and B-cell epitopes located in pre-S1 and pre-S2 proteins may lead to an immune evasion of the virus, likely favoring a more severe clinical course of infection. Furthermore, point and frame shift mutations in the core region increase the viral replication of HBV and help virus to evade from immune system and guarantee its persistence.

CONCLUSIONS

Fulminant hepatitis B is associated with distinct mutational patterns of HBV, underlining that genomic diversity of the virus is an important factor determining its pathogenicity.

Precore/basal core promoter mutants quantification throughout phases of hepatitis B virus infection by Simpleprobe

AIM: To investigate precore/basal core promoter (PC/BCP) mutants throughout hepatitis B virus (HBV) infection and to determine their relationship to hepatitis B early antigen (HBeAg) titers.

METHODS: We enrolled 191 patients in various stages of HBV infection at the Huashan Hospital and the Taizhou Municipal Hospital from 2010 to 2012. None of the patients received antiviral therapy. HBV DNA from serum, was quantified by real-time PCR. The HBV genotype was determined by direct sequencing of the S gene. We used the Simpleprobe ultrasensitive quantitative method to detect PC/BCP mutants in each patient. We compared the strain number, percentage, and the changes in PC/BCP mutants in different phases, and analyzed the relationship between PC/BCP mutants and HBeAg by multiple linear regression and logistic regression.

RESULTS: Patients with HBV infection (n = 191) were assigned to groups by phase: Immune tolerance (IT) = 55, Immune clearance (IC) = 67, Low-replicative (LR) = 49, and HBeAg-negative hepatitis (ENH) = 20. Of the patients (male, 112; female, 79) enrolled, 122 were HBeAg-positive and 69 were HBeAg-negative. The median age was 33 years (range: 18-78 years). PC and BCP mutation detection rates were 84.82% (162/191) and 96.86% (185/191), respectively. In five HBeAg-negative cases, we detected double mutation G1896A/G1899A. The logarithm value of PC mutant quantities (log₁₀ PC) significantly differed in IT, IC, and LR phases, as well as in the ENH phase (F = 49.350, P < 0.001). The logarithm value of BCP mutant quantities (log₁₀ BCP) also differed during the four phases (F = 25.530, P < 0.001). Log₁₀ PC and log₁₀ BCP values were high in the IT and IC phases, decreased in the LR phase, and increased in the ENH phase, although the absolute value at this point remained lower than that in the IT and IC phases. PC mutant quantity per total viral load (PC%) and BCP mutant quantity per total viral load (BCP%) differed between phases (F = 20.040, P < 0.001; F = 10.830, P < 0.001), with PC% and BCP% gradually increasing in successive phases. HBeAg titers negatively correlated with PC% (Spearman’s rho = -0.354, P < 0.001) and BCP% (Spearman’s rho = -0.395, P < 0.001). The negative correlation between PC% and HBeAg status was significant (B = -5.281, P = 0.001), but there was no such correlation between BCP% and HBeAg status (B = -0.523, P = 0.552).

CONCLUSION: PC/BCP mutants become predominant in a dynamic and continuous process. Log₁₀ PC, log₁₀ BCP, PC% and BCP% might be combined to evaluate disease progression. PC% determines HBeAg status.

Impact of HBV genotypes A and D genetic variability on infection evolution

HBV is characterized by a high genetic variability, which is the basis of its classification into eight genotypes (A-H). HBV infection is associated with different outcomes, from self-limiting acute hepatitis to active chronic hepatitis, asymptomatic carriage, and occult infection. The aim of this study was to analyze the genetic variability of HBV genotypes A and D isolates from 79 cases of self-limiting acute hepatitis and chronic hepatitis, in order to identify HBV variants associated with resolution or chronicity of acute HBV infection. The entire preS-S sequence and a fragment of 346 bp of the preC-C region, containing Enhancer II and Basal Core Promoter sequences, were analyzed. A phylogenetic analysis of preS/S region showed that the 45.45% (15/33) of isolates from acute hepatitis cases were genotype A compared to 8.69% (4/46) of chronic hepatitis cases. (p = 0.0002). Mutations associated with immune-escape (T131N, D144A/E, G145K), amino acid polymorphisms in "a determinant" domain of S protein and mutations/deletions in preC/C region were found in isolates from acute and chronic hepatitis B cases. In this study mutations/deletions in preS-S and preC-C regions, usually associated with fulminant acute hepatitis, advanced forms of liver disease and increased risk for HCC, were identified in HBV strains of genotype A and D obtained both from patients with self-limiting acute HBV infection and from persistent infected patients. This founding probably is due to the natural viral evolution under host immune response and to the circulation of a wide variety of HBV strains in our geographic area because of the ancient introduction of genotype D and the migrant fluxes from North Africa. Moreover, the analysis of circulation of new HBV antigenic variants is fundamental for the epidemiological surveys and for the evaluation of the impact of viral evolution on vaccine prophylaxis strategies.

Lower mutation frequency of BCP/precore regions in e antigen-negative chronic HBV-infected children instead of adults patients

To describe the Hepatitis B e antigen(HBeAg) seroconversion related mutation profiles of the basal core promoter(BCP)/precore regions in e antigen seroconverted child patients, a cohort of 245 child patients with CHB and a control patients group of 92 adult patients with CHB were recruited. The mutation frequencies of six nucleotides or nucleotide combinations including nucleotide (nt)1896, nt1762/1764, nt1752, nt1846, nt1899 and nt1753 showed significant differences between HBeAg positive and HBeAg-negative child patients groups. The frequencies of these HBeAg seroconversion-related mutations were significantly lower in HBeAg-negative children with CHB than in HBeAg-negative adults with CHB, especially for the mutation G1896A (41.1% vs 91.7%, P<0.001), and the average number of BCP/precore region mutations in samples from HBeAg-negative child patients was also obviously lower than in HBeAg-negative adult patients(3.62±3.03 vs 4.89±2.09, P<0.001), suggesting less impact of mutations in the BCP/precore region on HBeAg seroconversion in child patients than adult patients.

Association of Mutations in the Basal Core Promoter and Pre-core Regions of the Hepatitis B Viral Genome and Longitudinal Changes in HBV Level in HBeAg Negative Individuals: Results From a Cohort Study in Northern Iran

BACKGROUND

Although certain HBV mutations are known to affect the expression of Hepatitis e antigen, their association with HBV viral level or clinical outcomes is less clear.

OBJECTIVES

We evaluated associations between different mutations in the Basal Core promoter (BCP) and Pre-core (PC) regions of HBV genome and subsequent changes in HBV viral DNA level over seven years in a population of untreated HBeAg negative chronic hepatitis B (CHB) participants in Northeast of Iran.

MATERIALS AND METHODS

Participants in the current study were drawn from the Golestan Hepatitis B Cohort Study (GHBCS), a cohort of approximately 2590 HBsAg positive subjects (living in Gonbad city) embedded in the Golestan Cohort Study (GCS). At baseline, HBsAg was measured in all participants and revealed 2590 HBsAg positive cases. We randomly selected 304 participants who their blood sample were taken at both baseline and seven years later in follow-up and had not been treated for HBV during this time. HBV viral load were assessed at baseline and at year 7. The BCP and PC regions of the HBV DNA, at baseline, were amplified via hemi-nested PCR and sequenced by cycle sequencing. At year 7, liver stiffness was assessed by fibroscan; also, other parameters of liver disease were assessed following standard clinical protocols. Associations were assessed via tabulation, chi-square, t-tests and logistic regression. P values < 0.05 were considered statistically significant and all tests were two-sided.

RESULTS

Among 304 HBsAg positive participants, 99 had detectable HBV DNA at study baseline. Of these, 61.6% had PC mutations (48.5% A1896 and 25.2% G1899). In contrast to other mutations, A1896 was associated with a higher proportion of detectable HBV DNA at year 7 (39.6%) compared to patients with the wild type (13.7%) (OR: 4.36, CI95% = 1.63-11.70; P Value = 0.002). Although participants with the A1896 mutation had higher year-7 HBV viral load than participants with G1896 (2.30 ± 1.66 IU/mL vs. 1.76 ± 1 IU/mL among patients with detectable HBV; P value = 0.052), no association was observed with either serum level ALT or liver stiffness. Interestingly, mutations in the basal core promoter (BCP) region had no significant effect on virus DNA detection.

CONCLUSIONS

In this population with chronic HBeAg negative hepatitis B, an association was observed between the G1896A mutation in the Pre-core region of HBV and subsequent level of HBV DNA seven years later, which indicated that mutations in this region of HBV genome may contribute to disease progression in these patients and play an important role in HBV natural course of disease.

Clinical utility of complex mutations in the core promoter and proximal precore regions of the hepatitis B virus genome

The core promoter and proximal precore regions are the most complex portions of the hepatitis B virus (HBV) genome. These regions cooperatively regulate viral replication and differentially regulate the synthesis of the viral proteins E, core, and X. Multiple mutations in these regions are associated with the persistency of viral infection and the development of cirrhosis and hepatocellular carcinoma (HCC). In South Korea, nearly all HBVs are classified as HBV genotype C2; the majority of these viruses have the basal core promoter double mutation, a precore stop mutation, or both. These mutations may play a role in the alteration of viral and clinical features, and abundant and complex mutations are particularly prevalent in the core promoter and proximal precore regions. We previously demonstrated that the accumulation of ≥ 6 mutations at eight key nucleotides located in these regions (G1613A, C1653T, T1753V, A1762T, G1764A, A1846T, G1896A, and G1899A) is a useful marker to predict the development of HCC regardless of advanced liver disease. In addition, certain mutation combinations were predominant in cases with ≥ 4 mutations. In cases with ≤ 5 mutations, a low Hepatitis B e antigen titer (< 35 signal to noise ratio) was indicative of HCC risk. Viral mutation data of the single HBV genotype C2 suggest that the combined effect of the number and pattern of mutations in the core promoter and proximal precore regions is helpful in predicting HCC risk.

Correlation between the promoter basal core and precore mutations and HBsAg quantification in French blood donors infected with hepatitis B virus

Hepatitis B virus (HBV) basal core promoter (BCP) and precore (PC) mutations, HBV viral load and HBV surface antigen (HBsAg) quantitation were screened to assess correlations between these HBV markers in asymptomatic chronic hepatitis B carriers in France. From January 2006 to July 2007, 200 sera were collected from patients who were discovered to be HBsAg-positive when they volunteered to give blood. Direct sequencing of precore/core gene was used to detect A1762T/G1764A mutations in the BCP and G1896A in the PC region. HBV viral load and HBsAg were quantified with two commercials assays. The prevalence of the BCP and PC mixed/mutants were 37% and 60% respectively (P = 0.0001). HBV DNA level and HBsAg titer were significantly lower in subjects harboring the mixed/mutant PC virus compared to those infected by the wild phenotype. No significant difference was observed in HBV viral loads of blood donors infected by wild or mixed/mutant BCP viruses. Mutant or mixed PC virus was associated with male gender, HBeAb-positive status and HBV/D and HBV/E genotypes. BCP mutations were associated with age, and both HBV/A-HBV/E genotypes.The genetic properties of HBV in this cohort showed that most of the blood donors had a negative HBeAg serological status and harbored the PC mutant phenotype in combination with low levels of both HBV DNA and HBsAg. As the study was conducted in healthy subjects who could be considered as asmptomatic carriers, these results suggest a possible protective effect of the G1896A mutation against severe liver lesions.

Virus-related liver cirrhosis: molecular basis and therapeutic options

Chronic infections with hepatitis B virus (HBV) and/or hepatitis C virus (HCV) are the major causes of cirrhosis globally. It takes 10-20 years to progress from viral hepatitis to cirrhosis. Intermediately active hepatic inflammation caused by the infections contributes to the inflammation-necrosis-regeneration process, ultimately cirrhosis. CD8(+) T cells and NK cells cause liver damage via targeting the infected hepatocytes directly and releasing pro-inflammatory cytokine/chemokines. Hepatic stellate cells play an active role in fibrogenesis via secreting fibrosis-related factors. Under the inflammatory microenvironment, the viruses experience mutation-selection-adaptation to evade immune clearance. However, immune selection of some HBV mutations in the evolution towards cirrhosis seems different from that towards hepatocellular carcinoma. As viral replication is an important driving force of cirrhosis pathogenesis, antiviral treatment with nucleos(t)ide analogs is generally effective in halting the progression of cirrhosis, improving liver function and reducing the morbidity of decompensated cirrhosis caused by chronic HBV infection. Interferon-α plus ribavirin and/or the direct acting antivirals such as Vaniprevir are effective for compensated cirrhosis caused by chronic HCV infection. The standard of care for the treatment of HCV-related cirrhosis with interferon-α plus ribavirin should consider the genotypes of IL-28B. Understanding the mechanism of fibrogenesis and hepatocyte regeneration will facilitate the development of novel therapies for decompensated cirrhosis.

Hepatitis B virus genetic mutations and evolution in liver diseases

Hepatitis B virus (HBV) belongs to the genus Orthohepadnavirus of the Hepadnaviridae family and is approximately 3.2 kb in length. Owing to a lack of proofreading capacity during reverse transcription and a high replication rate, HBV exhibits as quasispecies. To detect the genetic mutations of HBV, many methods with different sensitivities and throughputs were developed. According to documentary records, HBV mutation and evolution were important vial parameters in predicting disease progression and therapeutic outcome. In this review, we separately discussed the correlation between HBV genomic mutations in four open reading frames and liver disease progression. Since some of the results were controversial from different laboratories, it remains to be seen whether functional analyses will confirm their role in modifying the course of infection.

Molecular characterization of HBV strains circulating among the treatment-naive HIV/HBV co-infected patients of eastern India

Previously we reported that the exposure to hepatitis B virus (HBV) infection serves as a major threat among the treatment naive HIV infected population of eastern India. Hence, molecular characterization of these strains is of utmost importance in order to identify clinically significant HBV mutations. A total of 85 treatment naive HIV/HBV co-infected participants were included of whom the complete basal core promoter/precore region, the core and the whole envelope gene could be successfully sequenced for 59, 57 and 39 isolates respectively. Following phylogenetic analysis, it was found that HBV/D was the predominant genotype with HBV/D2 (38.5%) being the most prevalent subgenotype followed by HBV/A1. The major mutations affecting HBeAg expression includes the A1762T/G1764A (13.6%), G1896A (22%) and G1862T mutation (33.9%) which was predominantly associated with HBV/A1. Moreover, the prevalence of G1896A was considerably high among the HBeAg negative HIV/HBV co-infected subjects compared to HBV mono-infection. The main amino acid substitutions within the MHC class II restricted T-cell epitope of HBcAg includes the T12S (15.8%) and T67N (12.3%) mutation and the V27I (10.5%) mutation in the MHC class I restricted T-cell epitope. PreS1/S2 deletion was detected in 3 isolates with all harboring the BCP double mutation. Furthermore, the frequently occurring mutations in the major hydrophilic loop of the S gene include the T125M, A128V and M133I/L. Therefore, this study is the first from India to report useful information on the molecular heterogeneity of the HBV strains circulating among the treatment naive HIV/HBV co-infected population and is thus clinically relevant.

Molecular characterization of hepatitis B virus (HBV) strains circulating in the northern coast of the Persian Gulf and its comparison with worldwide distribution of HBV subgenotype D1

Iran is a large country that covers the northern coast of the Persian Gulf. Iranian residents of this coastal region interact closely with people from neighboring countries because of historical and cultural relationships, as well as economic activities. In addition, the inhabitants of this border region have experienced several wars, which have affected public health infrastructures. This study characterized for the first time, the evolution of the full-length genome of HBV strains in asymptomatic carrier patients living in this particular region. In addition, this study was compared and complemented by a comprehensive evolutionary analysis of the worldwide geographical distribution of HBV subgenotype D1. Evolutionary analysis demonstrates that patients living in the northern coast of the Persian Gulf are mainly infected with HBV subgenotype D1, subtype ayw2. Specific mutations related to advanced liver disease were found more frequently in these strains compared to other strains isolated from asymptomatic carriers from other regions of Iran. This global comprehensive analysis showed that HBV subgenotype D1 strains have a worldwide distribution and that human mobility and immigration had a large impact on dispersal of HBV subgenotype D1, subtype ayw2 in Middle Eastern countries such as Iran, Syria, and Turkey. In addition to association of subtype ayw2 with subgenotype D1, it was demonstrated that other HBV subtypes like adw2, ayw1, and ayw3 are associated with HBV subgenotype D1 in different regions of the world. This study also revealed a remarkable distribution of subgenotype D1, subtype ayw4 although this particular subtype is associated with subgenotype D4 of HBV in European countries.

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.

Novel point mutations and mutational complexes in the enhancer II, core promoter and precore regions of hepatitis B virus genotype D1 associated with hepatocellular carcinoma in Saudi Arabia

In this study, a cohort of 182 patients [55 hepatocellular carcinoma (HCC) and 127 non-HCC] infected with hepatitis B virus (HBV) in Saudi Arabia was investigated to study the relationship between sequence variation in the enhancer II (EnhII), basal core promoter (BCP) and precore regions of HBV genotype D (HBV/D) and the risk of HCC. HBV genotypes were determined by sequencing analysis and/or enzyme-linked immunosorbent assay. Variations in the EnhII, BCP and precore regions were compared between 107 non-HCC and 45 HCC patients infected with HBV/D, followed by age-matched analysis of 40 cases versus equal number of controls. Age and male gender were significantly associated with HCC (p = 0.0001 and p = 0.03, respectively). Serological markers such as aspartate aminotransferase, albumin and anti-HBe were significantly associated with HCC (p = 0.0001 for all), whereas HBeAg positivity was associated with non-HCC (p = 0.0001). The most prevalent HBV genotype was HBV/D (94%), followed by HBV/E (4%), HBV/A (1.6%) and HBV/C (0.5%). For HBV/D1, genomic mutations associated with HCC were T1673/G1679, G1727, C1741, C1761, A1757/T1764/G1766, T1773, T1773/G1775 and C1909. Age- and gender-adjusted stepwise logistic regression analysis indicated that mutations G1727 [odds ratio (OR) = 18.3; 95% confidence interval (CI) = 2.8-118.4; p = 0.002], A1757/T1764/G1766 (OR = 4.7; 95% CI = 1.3-17.2; p = 0.01) and T1773 (OR = 14.06; 95% CI = 2.3-84.8; p = 0.004) are independent predictors of HCC development. These results implicate novel individual and combination patterns of mutations in the X/precore region of HBV/D1 as predictors of HCC. Risk stratification based on these mutation complexes would be useful in determining high-risk patients and improving diagnostic and treatment strategies for HBV/D1.

Quasispecies structure, cornerstone of hepatitis B virus infection: Mass sequencing approach

Hepatitis B virus (HBV) is a DNA virus with complex replication, and high replication and mutation rates, leading to a heterogeneous viral population. The population is comprised of genomes that are closely related, but not identical; hence, HBV is considered a viral quasispecies. Quasispecies variability may be somewhat limited by the high degree of overlapping between the HBV coding regions, which is especially important in the P and S gene overlapping regions, but is less significant in the X and preCore/Core genes. Despite this restriction, several clinically and pathologically relevant variants have been characterized along the viral genome. Next-generation sequencing (NGS) approaches enable high-throughput analysis of thousands of clonally amplified regions and are powerful tools for characterizing genetic diversity in viral strains. In the present review, we update the information regarding HBV variability and present a summary of the various NGS approaches available for research in this virus. In addition, we provide an analysis of the clinical implications of HBV variants and their study by NGS.

Genetic variability of hepatitis B and C viruses in Brazilian patients with and without hepatocellular carcinoma

Most cases of hepatocellular carcinoma (HCC) are due to chronic hepatitis B virus (HBV) or hepatitis C virus (HCV) infection worldwide. The aim of this study was to determine the viral genotypes and frequency of 17 mutations (15 for HBV and 2 for HCV), described previously as able to influence the course of chronic liver disease, in patients with and without HCC. This transversal study included 157 Brazilian patients with chronic hepatitis B (n = 51) and C (n = 106). Of these, 12 and 40 patients had HBV- and HCV-related HCC, respectively. Nucleotide sequencing of core promoter, pre-core, and pre-S/S regions of HBV and core region of HCV strains was performed to determine their genotypes and the frequency of the respective mutations. Among the HBV isolates, subgenotype A1 was the most prevalent in both patients with (90%) and without (61%) HCC. Fourteen out of the 15 mutations under study, as well as five different pre-S deletions, were identified. Core promoter T1753V, A1762T, and G1764A mutations were more frequent in patients with HCC than in those without, although with no statistical difference. However, a significant correlation was observed between T1753V mutation and elevation of transaminases levels (P < 0.05). As for HCV, mutation at residue 70 in the core protein of genotype 1b strains was significantly more frequent in patients with cirrhosis (56.3%) than in those without (9.1%) (P = 0.018). The detection of some key mutations in the genomes of HBV and HCV might be helpful to predict the clinical outcome of patients with chronic liver disease.

Evaluation of PCR-RFLP in the Pre-S Region as Molecular Method for Hepatitis B Virus Genotyping

BACKGROUND

Hepatitis B virus (HBV) infection is a public health problem in developing countries. HBV genotypes play major role in the evolution of infection since they were involved in different clinical presentations and response to treatment.

OBJECTIVES

This study was conducted to evaluate the efficiency of restriction fragment length polymorphism (RFLP) analysis for HBV genotyping.

PATIENTS AND METHODS

We investigated 98 samples collected from patients chronically infected with HBV. HBV genotypes were determined by analysis of patterns obtained after amplification in Pre-S region and digestion of the amplicon by two endonucleases AvaII and DpnII. Obtained results were confirmed by partial sequencing in the same region.

RESULTS

Two different HBV genotypes were detected in this study, Genotype D (in 95. 9%) and Genotype A (in 4.1%). Seventy-four samples (75.5%) were successfully genotyped with RFLP analysis and all classified as genotype D. The remaining 24 samples (24.5%) which were un-genotyped by RFLP analysis, were classified by partial sequencing of the pre-S region as HBV genotype D (20 samples, 20.4%) and genotype A (4 samples, 4.1%). Atypical profiles were significantly associated with advanced liver disease (P = 0.001) as well as older age (P < 0.05).

CONCLUSIONS

Several previous studies used PCR-RFLP to genotype HBV; however, we showed the high risk to obtain atypical profiles, especially in advanced stages of chronic infection, with as results difficulties to genotype the virus. These profiles resulted from the accumulation of mutations during natural course of infection resulting in a modification in restriction sites for enzymes. So, we recommended completing the investigation by partial sequencing to confirm obtained results.

Polymorphic APOBEC3 modulates chronic hepatitis B in Moroccan population

The cytidine deaminase apolipoprotein B mRNA editing catalytic subunit-3 (APOBEC3) induces G-to-A hypermutation in hepatitis B virus (HBV) genomes and operates as part of the innate antiviral immune system. We investigated the associations between the presence of APOBEC3 variants and HBV carriage in a case-control study in the Moroccan population. A polymorphic deletion affecting the APOBEC3B gene and the H186R variant of APOBEC3G were genotyped in 179 HBV chronic carriers and 216 healthy control subjects. In addition, to assess the overall impact of APOBEC3 deaminases on circulating HBV, we looked for hyperedited forms of the viral genome using the 3DPCR technique and analysed editing context. Data analysis showed that there was no significant difference in the frequencies of deleted APOBEC3B alleles (P = 0.261) or genotypes (P = 0.333) between patients with chronic hepatitis B and control subjects. By contrast, subjects bearing deleted genotype had a faster progression of liver disease than those with the insertion genotype (adjusted OR, 3.72; 95% CI, 0.38-36.12). The analysis of the APOBEC3G H186R polymorphism revealed that R/R genotype frequencies were not significantly different in HBV infected patients and in healthy subjects. 3DPCR was positive in 26 samples (14%) among 179. Amplified viral segments displayed monomorphic G>A transitions highly reminiscent of APOBEC3G activity. Most intriguingly, hemi/homozygous carriers of the APOBEC3B deletion had significantly lower virus loads than patients with the wild type (median 539 vs. 2213 IU/mL, P = 0.0023). This result suggests that genetic variations in APOBEC3 cytidine deaminases do not predispose to chronicity but may modulate the course of persistent HBV infection.

HLA-DP polymorphisms affect the outcomes of chronic hepatitis B virus infections, possibly through interacting with viral mutations

Genetic polymorphisms of HLA-DP have been associated with hepatitis B virus (HBV) persistence. We aimed to determine the effect of HLA-DP polymorphisms on the generation of HBV mutations and their interactions on the outcomes of HBV infection. rs3077, rs3135021, rs9277535, and rs2281388 were genotyped in 1,342 healthy controls, 327 HBV clearance subjects, and 2,736 HBV-positive subjects, including 1,108 hepatocellular carcinoma (HCC) patients, using quantitative PCR. HBV mutations were determined by sequencing. Multiplicative interactions of HLA-DP polymorphisms and viral mutations were assessed by multivariate logistic regression. rs3077 (from subjects with genotype CT combined with those from subjects with genotype TT [CT+TT] versus CC), rs3135021 (GA+AA versus GG), rs9277535 (GA+AA versus GG), and rs2281388 (CC versus CT+TT) significantly decreased HBV persistence. This effect was found only in genotype B HBV-infected subjects compared to HBV clearance subjects. HLA-DP polymorphisms promoting HBV clearance were associated with a lower prevalence of mutations increasing HCC risk (C1653T, T1674C/G, A1846T, G1896A and pre-S2 mutations and pre-S deletion in genotype C) and a higher prevalence of mutations decreasing HCC risk (G1652A, T1673C, T1674C, G1719T, G1730C, and G1799C in genotype B and A1727T in genotype C). Significant effects of viral mutations on cirrhosis and HCC were selectively evident in those with HLA-DP polymorphisms promoting HBV persistence. The interactions of C1653T, T1674C/G, and G1896A mutations with HLA-DP polymorphisms promoting HBV clearance significantly decreased cirrhosis risk. The interaction of rs9277535 AA with the T1674C/G or G1719T mutation in genotype C significantly decreased HCC risk. In conclusion, HLA-DP polymorphisms affect genotype B HBV clearance, regulate immune selection of viral mutations, and influence cirrhosis and HCC risks contributed by HBV mutations.

Hepatitis B virus subgenotype C2- and B2-associated mutation patterns may be responsible for liver cirrhosis and hepatocellular carcinoma, respectively

The objective of this study was to examine hepatitis B virus (HBV) subgenotypes and mutations in enhancer II, basal core promoter, and precore regions of HBV in relation to risks of liver cirrhosis (LC) and hepatocellular carcinoma (HCC) in Southeast China. A case-control study was performed, including chronic hepatitis B (CHB; n=125), LC (n=120), and HCC (n=136). HBV was genotyped by multiplex polymerase chain reaction and subgenotyped by restriction fragment length polymorphism. HBV mutations were measured by DNA sequencing. HBV genotype C (68.2%) predominated and genotype B (30.2%) was the second most common. Of these, C2 (67.5%) was the most prevalent subgenotype, and B2 (30.2%) ranked second. Thirteen mutations with a frequency >5% were detected. Seven mutation patterns (C1653T, G1719T, G1730C, T1753C, A1762T, G1764A, and G1799C) were associated with C2, and four patterns (C1810T, A1846T, G1862T, and G1896A) were associated with B2. Six patterns (C1653T, G1730C, T1753C, A1762T, G1764A, and G1799C) were obviously associated with LC, and 10 patterns (C1653T, G1730C, T1753C, A1762T, G1764A, G1799C, C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with CHB. Four patterns (C1810T, A1846T, G1862T, and G1896A) were significantly associated with HCC compared with LC. Multivariate regression analyses showed that HBV subgenotype C2 and C2-associated mutation patterns (C1653T, T1753C, A1762T, and G1764A) were independent risk factors for LC when CHB was the control, and that B2-associated mutation patterns (C1810T, A1846T, G1862T, and G1896A) were independent risk factors for HCC when LC was the control.

Increased CD163 expression is associated with acute-on-chronic hepatitis B liver failure

AIM: To assess CD163 expression in plasma and peripheral blood and analyze its association with disease in acute-on-chronic hepatitis B liver failure (ACHBLF) patients.

METHODS: A retrospective study was conducted from January 1, 2011 to January 1, 2012. Forty patients with ACHBLF (mean age 44.48 ± 12.28 years, range 18-69 years), 40 patients with chronic hepatitis B (CHB) (mean age 39.45 ± 12.22 years, range 21-57 years) and 20 age- and sex-matched healthy controls (mean age 38.35 ± 11.97 years, range 28-60 years) were included in this study. Flow cytometry was used to analyze the frequency of CD163+ peripheral blood mononuclear cells (PBMCs) and surface protein expression of CD163. Real-time transcription-polymerase chain reaction was performed to assess relative CD163 mRNA levels in PBMCs. Plasma soluble CD163 (sCD163) levels were measured by enzyme-linked immunosorbent assay. Clinical variables were also recorded. Comparisons between groups were analyzed by Kruskal-Wallis H test and Mann-Whitney U test. Statistical analyses were performed using SPSS 15.0 software and a P value < 0.05 was considered statistically significant.

RESULTS: Flow cytometry showed that the population of CD163+ PBMCs was significantly greater in ACHBLF patients than in CHB patients and healthy controls (47.9645% ± 17.1542%, 32.0975% ± 11.0215% vs 17.9460% ± 6.3618%, P < 0.0001). However, there were no significant differences in mean fluorescence intensity of CD163+ PBMCs within the three groups (27.4975 ± 11.3731, 25.8140 ± 10.0649 vs 20.5050 ± 6.2437, P = 0.0514). CD163 mRNA expression in ACHBLF patients was significantly increased compared with CHB patients and healthy controls (1.41 × 10^-2± 2.18 × 10^-2, 5.10 × 10^-3± 3.61 × 10^-3vs 37.0 × 10^-4± 3.55 × 10^-4, P = 0.02). Plasma sCD163 levels in patients with ACHBLF were significantly increased compared with CHB patients and healthy controls (4706.2175 ± 1681.1096 ng/mL, 1089.7160 ± 736.8395 ng/mL vs 435.9562 ± 440.8329 ng/mL, P < 0.0001). In ACHBLF patients, plasma sCD163 levels were significantly positively associated with model for end-stage liver disease scores (r = 0.5075, P = 0.008), hepatitis B virus-DNA (r = 0.6827, P < 0.0001), and negatively associated with prothrombin activity (r = -0.3348, P = 0.0347), but had no correlation with total bilirubin (r = 0.2551, P = 0.1122). Furthermore, sCD163 was obviously elevated in non-surviving patients compared with surviving patients with ACHBLF (5344.9080 ± 1589.5199 ng/mL vs 3641.7333 ± 1264.5228 ng/mL, P = 0.0321).

CONCLUSION: CD163 and sCD163 may be related to disease severity and prognosis in ACHBLF patients.