Expression levels of HBV pregenomic RNA and hepatitis B core-related antigen in circulating serum and their association with recurrence in chronic hepatitis B patients after withdrawal from nucleos(t)ide analogues / 临床肝胆病杂志

Objective To investigate the expression levels of HBV pregenomic RNA (pgRNA) and hepatitis B core-related antigen (HBcrAg) in circulating serum of chronic hepatitis B (CHB) patients after withdrawal from nucleos(t)ide analogues (NUC), as well as the correlation of HBV pgRNA and HBcrAg levels in circulating blood in different periods of time with recurrence in CHB patients after drug withdrawal. Methods Among the patients who attended the outpatient service of Affiliated Hospital of North Sichuan Medical College from December 2019 to July 2022, a total of 108 CHB patients who received anti-HBV therapy for at least 5 years and met the criteria for drug withdrawal in 2017 EASL Guidelines were enrolled. According to the time of drug withdrawal, the patients were divided into 4-, 12-, and 24-week groups after drug withdrawal, and according to the presence or absence of recurrence, they were divided into recurrence group and non-recurrence group. Quantitative real-time PCR was used to measure the level of HBV pgRNA in circulating serum of CHB patients; ELISA was used to measure the expression level of HBcrAg in peripheral venous blood; quantitative real-time PCR was used to measure HBV DNA load with high accuracy. The t -test was used for comparison of continuous data between two groups. A one-way analysis of variance was used for comparison of continuous data between multiple groups, and the least significant difference t -test was used for further comparison between two groups. The Pearson correlation test was used to investigate the correlation between the indices in circulating blood. Results For the CHB patients after drug withdrawal, the recurrence rate was 17.1% at 4-12 weeks, cumulative recurrence rate reached 29.3% after 24 weeks of follow-up, the patients with positive HBV DNA alone accounted for 64.3% and 60.0%, respectively, those with positive HBeAg alone accounted for 28.5% and 20.0%, respectively, and those with positive HBV DNA and HBeAg accounted for 7.1% and 20.0%, respectively. The expression levels of HBV pgRNA, HBcrAg, and HBV DNA in circulating serum of CHB patients at 24 weeks after drug withdrawal were significantly higher than those at the time of drug withdrawal and at 4 weeks after drug withdrawal, and there was a significant difference between groups at different time points (all P 0.05). Conclusion The recurrence group had significantly higher expression levels of HBV pgRNA and HBcrAg than the non-recurrence group at the time of drug withdrawal, suggesting that the levels of HBV pgRNA and HBcrAg in the CHB patients of the non-recurrence group at the time of drug withdrawal may be used as the reference thresholds for safe drug withdrawal in CHB patients, and measurement of HBV pgRNA and HBcrAg may be one of the potential reference indicators for the selection of anti-HBV treatment endpoints in the future.

Hepatitis B virus core-related antigen: A promising new serum marker for hepatitis B virus / 临床肝胆病杂志

Hepatitis B virus core-related antigen (HBcrAg) is a new serum biomarker for hepatitis B virus (HBV) and is composed of several antigens encoded by the pre-C/C region gene of HBV, including HBcAg, HBeAg, and P22cr precursor protein. There is a poor correlation between HBcrAg and HBsAg and they cannot replace each other. Serum HBcrAg level can reflect the content and transcriptional activity of cccDNA in hepatocytes of patients with chronic hepatitis B, as well as the transcriptional activity of integrated HBV DNA. In addition, HBcrAg can be used to evaluate the antiviral effect of nucleos(t)ide analogues and pegylated interferon- and predict recurrence risk after withdrawal of nucleos(t)ide analogues and the development risk and recurrence of hepatocellular carcinoma after surgery. Therefore, serum HBcrAg is a promising new serum marker for HBV.

New Biomarkers of Chronic Hepatitis B

Chronic hepatitis B (CHB) infection leads to clinically heterogeneous disease outcomes. Different viral markers are utilized to monitor treatment effects and predict risk of complications in patients with CHB. Hepatitis B core-related antigen (HBcrAg) is a novel serum composite viral protein whose performance has been proven to be superior to that of existing viral markers. It showed good correlation with intrahepatic covalently closed-circular DNA. Its profile differs drastically in patients in different disease phases, and the level declines with antiviral therapies. HBcrAg may be helpful for predicting hepatocellular carcinoma development and hepatitis B virus (HBV) reactivation in immunosuppressed patients. Another emerging measurable serum marker, HBV RNA, exists in the form of pregenomic RNA-containing virions. Its profile differs between patients in different disease phases in a similar manner to that of HBcrAg. HBV RNA is present in serum at lower levels than HBV DNA in treatment-naive patients by 1–2 logs. In contrast, its level is higher than HBV DNA in patients receiving nucleos(t)ide analogues (NAs). A significant decline in serum RNA was observed in patients receiving novel antiviral therapies, including core protein allosteric modulators and RIG-1/NOD2 agonists. Both HBcrAg and HBV RNA may be helpful for predicting off-therapy sustained virological control in patients who stop long-term NA treatment.

Performance of Hepatitis B Core-Related Antigen Versus Hepatitis B Surface Antigen and Hepatitis B Virus DNA in Predicting HBeAg-positive and HBeAg-negative Chronic Hepatitis

BACKGROUND: We examined changes in hepatitis B core-related antigen (HBcrAg) during the four sequential phases of chronic hepatitis B virus (HBV) infection: hepatitis B e antigen (HBeAg)-positive chronic infection (EPCI) and hepatitis (EPCH), followed by HBeAg-negative chronic infection (ENCI) and hepatitis (ENCH). We compared the performance of serum HBcrAg, hepatitis B surface antigen (HBsAg), and HBV DNA in predicting EPCH and ENCH. METHODS: We enrolled 492 consecutive patients: 49 with EPCI, 243 with EPCH, 101 with ENCI, and 99 with ENCH. HBcrAg was detected by chemiluminescent enzyme immunoassays. HBsAg and HBeAg were detected by chemiluminescent microparticle immunoassays. HBV DNA was detected by real-time PCR. Predictive performance of HBcrAg, HBsAg, and HBV DNA was evaluated using ROC curves. RESULTS: Areas under ROC curves (AUCs) of HBcrAg, HBsAg, and HBV DNA for predicting EPCH were 0.738, 0.812, and 0.717, respectively; optimal cutoffs were ≤1.43×105 kU/mL, ≤1.89×104 IU/mL, and ≤3.97×107 IU/mL, with sensitivities and specificities of 66.3% and 77.6%, 65.0% and 93.9%, and 60.5% and 79.6%, respectively. AUCs of HBcrAg, HBsAg, and HBV DNA for predicting ENCH were 0.887, 0.581, and 0.978, respectively; optimal cutoffs were >26.8 kU/mL, >2.29×102 IU/mL, and >8.75×103 IU/mL, with sensitivities and specificities of 72.7% and 95.1%, 86.9% and 39.6%, and 89.9% and 92.1%, respectively. CONCLUSIONS: HBsAg and HBV DNA were the best predictors of EPCH and ENCH, respectively. HBcrAg is an important surrogate marker for predicting EPCH and ENCH.

Significance of hepatitis B virus pregenomic RNA in the progression of chronic hepatitis B / 临床肝胆病杂志

Hepatitis B virus (HBV) pregenomic RNA (pgRNA) is the direct transcription product of HBV covalently closed circular DNA (cccDNA) and can reflect the transcriptional activity of HBV cccDNA and the progression of chronic hepatitis B, which provides guidance for clinical treatment and prognostic prediction. Compared with other common serological markers for HBV infection, HBV pgRNA is more sensitive in reflecting HBV replication and the effect of antiviral therapy has a certain predictive value for endpoints in the stages of antiviral therapy. This article elaborates on the significance of HBV pgRNA in reflecting the changes in disease conditions with reference to the correlation of HBV pgRNA with HBcrAg and HBV cccDNA.