Biomarkers for hepatitis B virus replication: an overview and a look to the future

Study on the role of histone epigenetic modification in replication of hepatitis B virus

Hepatitis B virus (HBV) infection is a global health problem and lacks effective therapies in clinic. This study attempted to investigate the role of histone deacetylase 3 (HDAC3) in HBV replication. Cells were treated with 1.3 folds of HBV genome. The expression patterns of HDAC3, miR-29a-3p, and nuclear factor of activated T-cells 5 (NFAT5) in cells were determined by real-time quantitative polymerase chain reaction and Western blot analysis. HBV replication was assessed by measurements of HBV DNA, HBV RNA, hepatitis B surface antigen, and hepatitis B E antigen. After chromatin immunoprecipitation and RNA pull-down assays to testify gene interactions, rescue experiments and animal experiments were performed to assess the role of miR-29a-3p/NFAT5 in HBV replication and the role of HDAC3 in vivo. HDAC3 level was decreased by pHBV1.3 plasmid in a concentration-dependent manner. HDAC3 overexpression can inhibit HBV replication, which was neutralized by miR-29a-3p overexpression or NFAT5 downregulation. Mechanically, HDAC3 overexpression reduced the enrichment of histone 3 lysine 9 acetylation on the miR-29a-3p promoter to inhibit miR-29a-3p expression and then promote NFAT5 transcription. In vivo, HDAC3 restrained HBV replication through the miR-29a-3p/NFAT5 axis. Overall, HDAC3 downregulation was associated with HBV replication and HDAC3 overexpression inhibited HBV replication through H3K9ac/miR-29a-3p/NFAT5.

Hepatitis C virus/Hepatitis B virus coinfection: Current prospectives

In endemic areas, hepatitis C virus (HCV)/hepatitis B virus (HBV) coinfection is common, and patients with coinfection have a higher risk of developing liver disease such as hepatocellular carcinoma, liver fibrosis and cirrhosis. In such cases, HCV predominates, and HBV replication is suppressed by HCV. HCV core proteins and interferons that are activated by HCV are responsible for the suppression of HBV. Immunosuppression is also seen in patients with HCV and HBV coinfections. A decrease in HCV-neutralizing antibody response and circulation of Th1-like Tfh cells is observed in patients with HCV and HBV coinfection. Both viruses interacted in the liver, and treatment of HCV/HBV coinfection is genotype-based and complex due to the interaction of both viruses. In HCV-dominant cases, direct-acting antiviral drugs and peg interferon plus ribavirin are used for the treatment, with continuous monitoring of AST and ALT. HBV-dominant cases are less common and are treated with peg interferon and nucleoside nucleotide analogues with monitoring of AST and ALT. The SVR rate in HCV-HBV coinfection is higher than that in monoinfection when treated with direct-acting antiviral drugs. But there is a risk of reactivation of HBV during and after therapy. The rate of reactivation is lower in patients treated with direct-acting antiviral drugs as compared to those treated with peg interferon plus ribavirin. Biomarkers of HBV such as HBcrAg, HBV DNA and HBVpg RNA are not effective in the prediction of HBV reactivation; only the hepatitis B surface antigen titre can be used as a biomarker for HBV reactivation. HCV can also be reactive, but this is found in very rare cases in which HBV is present and is treated first.

Bulevirtide monotherapy for 48 weeks in patients with HDV-related compensated cirrhosis and clinically significant portal hypertension

BACKGROUND & AIMS

Bulevirtide (BLV) has recently been conditionally approved for the treatment of chronic hepatitis delta (CHD) in Europe, but its effectiveness and safety in patients with compensated cirrhosis and clinically significant portal hypertension (CSPH) are unknown.

METHODS

Consecutive patients with HDV-related compensated cirrhosis and CSPH who started BLV 2 mg/day were enrolled in this single-center study. Clinical/virological characteristics were collected at baseline, weeks 4, 8 and every 8 weeks thereafter. HDV RNA was quantified by Robogene 2.0 (lower limit of detection 6 IU/ml).

RESULTS

Eighteen Caucasian patients with compensated cirrhosis and CSPH under nucleos(t)ide analogue treatment were enrolled: median (IQR) age was 48 (29-77) years, and 67% were male. Median (IQR) platelet count was 70 (37-227) x10³/μl, liver stiffness measurement (LSM) 16.4 (7.8-57.8) kPa, alanine aminotransferase (ALT) 106 (32-222) U/L, HBsAg 3.7 (2.5-4.3) log IU/ml, HDV RNA 4.9 (3.3-6.6) log IU/ml. During 48 weeks of BLV monotherapy, HDV RNA declined by 3.1 (0.2-4.3) log IU/ml (p <0.001 vs. baseline), becoming undetectable in 5 patients (23%). A virological response was observed in 14 (78%) patients while a non-response was observed in 2 (11%). ALT decreased to 35 (15-86) U/L (p <0.001 vs. baseline), normalizing in 83% of patients. A combined response was observed in 67% of patients. Aspartate aminotransferase and gamma-glutamyltransferase levels significantly improved. Concerning liver function parameters, albumin values significantly increased and bilirubin remained stable. LSM significantly improved in patients with virological response, while platelet count was unchanged. None of the patients developed decompensating events or hepatocellular carcinoma. BLV was well tolerated, no patient discontinued treatment and the increase in bile acids was fully asymptomatic.

CONCLUSIONS

A 48-week course of BLV 2 mg/day monotherapy is safe and effective even for difficult-to treat patients with HDV-related compensated cirrhosis and CSPH.

LAY SUMMARY

Hepatitis delta virus (HDV) is associated with the most severe form of viral hepatitis. A new treatment for HDV called bulevirtide has recently received conditional approval for patients with chronic HDV infection. However, its safety and effectiveness in patients with more advanced liver disease is not known. Herein, we show that it is safe and effective in patients with HDV-related cirrhosis and clinically significant portal hypertension.

Risk Factors of Chronic Kidney Disease in Chronic Hepatitis B: A Hospital-based Case-control Study from China

BACKGROUND AND AIMS

Chronic kidney disease (CKD) usually occurs during the chronic infection of hepatitis B virus (HBV). However, the risk factors of CKD in an HBV population have not been completely demonstrated. Our present study aimed to investigate the risk factors of CKD in chronic HBV infection using a hospital based cross-sectional study in the northern area of China.

METHODS

During January 2013 to December 2017, a total of 94 patients with CKD complicated by chronic HBV infection were consecutively enrolled in the study, as well as 548 age- and sex-matched hepatitis B patients without CKD who were enrolled as controls. Univariate and multivariate regression analyses were used to determine the effects of each variable after adjusting for cofounding factors.

RESULTS

Multivariate analysis showed that HBeAg-positive status (odds ratio [OR]=2.099, 95% CI 1.128-3.907), dyslipidemia (OR: 3.025, 95% CI 1.747-5.239), and hypertension (OR: 12.523, 95% CI 6.283-24.958) were independently associated with the incidence of CKD, while duration of HBV infection (≥240 months) (OR: 0.401, 95% CI 0.179-0.894), Log₁₀ HBsAg (OR: 0.514, 95% CI 0.336-0.786), and coronary heart disease (OR: 0.078, 95% CI 0.008-0.768) were protective factors for the incidence of CKD. Duration of HBV infection, Log₁₀ HBsAg, HBeAg-positive status and dyslipidemia remained the risk factors for CKD after adjusting for diabetes mellitus, hypertension, and coronary heart disease.

CONCLUSIONS

Duration of HBV infection, Log₁₀ HBsAg, HBeAg-positive status and dyslipidemia contributed to the incidence of CKD during chronic HBV infection in a Chinese population.

Current laboratory tests for diagnosis of hepatitis B virus infection

BACKGROUND

Hepatitis B virus (HBV) has a long history in human infectious diseases. HBV infection can progress chronically, leading to cancer. After introduction of a vaccine, the overall incidence rate of HBV infection has decreased, although it remains a health problem in many countries.

PURPOSE

The aim of this review was to summarise current diagnostic efforts for HBV infection and future HBV diagnosis perspectives.

METHODS

We reviewed and summarised current laboratory diagnosis related with HBV infection in clinical practice.

RESULTS

There have been various serologic- and molecular-based methods to diagnose acute or chronic HBV infection. Since intrahepatic covalently closed circular DNAs (cccDNAs) function as robust HBV replication templates, cure of chronic HBV infection is limited. Recently, new biomarkers such as hepatitis B virus core-related antigen (HBcrAg) and HBV RNA have emerged that appear to reflect intrahepatic cccDNA status. These new biomarkers should be validated before clinical usage.

CONCLUSION

An effective diagnostic approach and current updated knowledge of treatment response monitoring are important for HBV infection management. Brand new ultrasensitive and accurate immunologic methods may pave the way to manage HBV infection in parallel with immunotherapy era.