Contribution of NK cells to HBsAg seroconversion in inactive HBsAg carriers following pegylated IFN therapy

Interpretable machine learning model for prediction functional cure in chronic hepatitis B patients receiving Peg-IFN therapy: A multi-center study

BACKGROUND

Functional cure is the ideal treatment goal for chronic hepatitis B (CHB) treatment. We developed and validated machine learning (ML) models to predict functional cure in CHB patients.

METHODS

This study retrospectively recruited 534 CHB patients who received Peg-IFN treatment to construct model and 269 patients for external validation. We analyzed three strategies: baseline, week 12, week 24. Seven ML models were constructed using selected variables by Boruta and least absolute shrinkage and selection operator regression algorithm, and performance metrics, including area under the curve (AUC), sensitivity, specificity, and F1 score were applied to determine the best model. We utilized SHapley Additive exPlanation to visualize and interpret the best model and built a website to conveniently predict functional cure of CHB.

RESULTS

A total of 272 participants were cured in our study. Compared to baseline and week 12 strategies, week 24 using Support Vector Machine (SVM) model can better predict functional cure of CHB, with reliable predictive performance (AUC = 0.981), calibration and clinical applicability in external validation cohort. Age, ALT ratio at week 12, HBsAg at week 24 and HBsAg ratio at week 24 were important features. In order to enhance clinical convenience and effectiveness of the constructed model, a web-based dynamic nomogram was created (Dynamic Nomogram (shinyapps.io)).

CONCLUSION

This study developed SVM model to predict functional cure in CHB patients treated with Peg-IFN. Furthermore, we also built a website that clinicians can individualized predict the efficacy of Peg-IFN therapy in CHB patients.

Safety and efficacy of 48-week pegylated interferon-α-2b therapy in patients with hepatitis B virus-related compensated liver cirrhosis: a pilot observational study

Background

Pegylated interferon-α (PEG-IFN-α) therapy could decrease hepatitis B surface antigen (HBsAg) and improve long-term prognosis of hepatitis B virus (HBV) infection. However, studies on safety and efficacy of PEG-IFN-α for patients with HBV-related cirrhosis are limited.

Methods

This was a single-center study. Fifty-four patients with HBV-related compensated cirrhosis were enrolled. All patients received subcutaneous injection of PEG-IFN-α-2b 180 μg per week for 48 weeks. The monotherapy of PEG-IFN-α-2b was used for treatment-naïve patients, while addition of PEG-IFN-α-2b to on-going nucleos(t)ide analogs (NAs) was used for NAs-experienced patients. Clinical symptoms, laboratory tests, examination indicators, and adverse events were collected at each observational time point.

Results

Forty-two patients achieved undetectable serum HBV DNA at 48 weeks post-therapy. HBsAg level was significantly reduced at 48 weeks post-therapy (227.2 IU/mL vs. 1,668 IU/mL; p < 0.001), especially in NAs-experienced patients (161.0 IU/mL vs. 1,207 IU/mL; p = 0.005). Three patients achieved HBsAg loss, and two of them obtained HBsAg seroconversion. There were no significant differences in liver stiffness measurement, thickness and length of spleen, or diameter of portal vein between baseline and 48 weeks post-therapy (p > 0.05). The aminotransferase levels were increased, while white blood cells, neutrophils, and platelets counts were decreased during PEG-IFN-α-2b therapy (p < 0.05), especially in treatment-naïve patients. Three patients discontinued PEG-IFN-α-2b therapy due to severe adverse events. No patients suffered with virological breakthrough or progressed to end-stage liver diseases during observational period.

Conclusion

A finite course of PEG-IFN-α-2b therapy was well-tolerated, and reduced HBsAg level without accelerating disease progression in patients with HBV-related compensated cirrhosis.

Clinical trial registration

This trial is a part of ZhuFeng Project (ClinicalTrials.gov, identifier NCT04035837).

Recurrence and influencing factors of hepatitis B surface antigen seroclearance induced by peginterferon alpha-based regimens

BACKGROUND

The long-term stability of hepatitis B surface antigen (HBsAg) seroclearance following peginterferon alpha (peg-IFN-α)-based therapy has not been extensively studied, leaving the full potential and limitations of this strategy unclear.

AIM

To assess HBsAg recurrence after seroclearance achieved by peg-IFN-α regimens.

METHODS

This prospective, multicenter, observational study was conducted from November 2015 to June 2021 at three Chinese hospitals: The Second Affiliated Hospital of Xi'an Jiaotong University, Ankang Central Hospital, and The Affiliated Hospital of Yan'an University. Participants who achieved HBsAg seroclearance following peg-IFN-α-based treatments were monitored every 4-12 weeks post-treatment for hepatitis B virus (HBV) markers, HBV DNA, and liver function. The primary outcome was HBV recurrence, defined as the reemergence of HBsAg, HBV DNA, or both, at least twice within 4-8 weeks of follow-up.

RESULTS

In total, 121 patients who achieved HBsAg seroclearance were enrolled. After a median follow-up of 84.0 (48.0, 132.0) weeks, four subjects were lost to follow-up. HBsAg recurrence was detected in 16 patients. The cumulative HBsAg recurrence rate in the intention-to-treat population was 15.2%. Multivariate logistic regression analysis demonstrated that consolidation time < 12 weeks [odds ratio (OR) = 28.044, 95%CI: 4.525-173.791] and hepatitis B surface antibody disappearance during follow-up (OR = 46.445, 95%CI: 2.571-838.957) were strong predictors of HBsAg recurrence. HBV DNA positivity and decompensation of liver cirrhosis and hepatocellular carcinoma were not observed.

CONCLUSION

HBsAg seroclearance following peg-IFN-α treatment was durable over 84 weeks of follow-up with a cumulative recurrence rate of 15.2%.

Mechanism of interferon alpha therapy for chronic hepatitis B and potential approaches to improve its therapeutic efficacy

Hepatitis B virus (HBV) chronically infects 296 million people worldwide and causes more than 820,000 deaths annually due to cirrhosis and hepatocellular carcinoma. Current standard-of-care medications for chronic hepatitis B (CHB) include nucleos(t)ide analogue (NA) viral DNA polymerase inhibitors and pegylated interferon alpha (PEG-IFN-α). NAs can efficiently suppress viral replication and improve liver pathology, but not eliminate or inactivate HBV covalently closed circular DNA (cccDNA). CCC DNA is the most stable HBV replication intermediate that exists as a minichromosome in the nucleus of infected hepatocyte to transcribe viral RNA and support viral protein translation and genome replication. Consequentially, a finite duration of NA therapy rarely achieves a sustained off-treatment suppression of viral replication and life-long NA treatment is most likely required. On the contrary, PEG-IFN-α has the benefit of finite treatment duration and achieves HBsAg seroclearance, the indication of durable immune control of HBV replication and functional cure of CHB, in approximately 5% of treated patients. However, the low antiviral efficacy and poor tolerability limit its use. Understanding how IFN-α suppresses HBV replication and regulates antiviral immune responses will help rational optimization of IFN therapy and development of novel immune modulators to improve the rate of functional cure. This review article highlights mechanistic insight on IFN control of HBV infection and recent progress in development of novel IFN regimens, small molecule IFN mimetics and combination therapy of PEG-IFN-α with new direct-acting antivirals and therapeutic vaccines to facilitate the functional cure of CHB.

Functional molecular expression of nature killer cells correlated to HBsAg clearance in HBeAg-positive chronic hepatitis B patients during PEG-IFN α-2a therapy

OBJECTIVE

To explore whether the frequencies and functional molecules expression of Natural Killer cells (NK cells) are related to hepatitis B surface antigen (HBsAg) disappearance in hepatitis B e envelope antigen (HBeAg)-positive patients with chronic hepatitis B (CHB) throughout peginterferon alpha-2a (PEG-IFN α-2a) treatment.

METHODS

In this prospective research, HBeAg-positive patients with CHB received PEG-IFN α-2a treatment, completing 4-year follow-up. After PEG-IFN α-2a treatment, undetectable HBV DNA, HBsAg loss, and HBeAg disappearance were defined as functional cure. Proportions of NK, CD56dim, CD56bright, NKp46+, NKp46dim, NKp46high, and interferon alpha receptor 2 (IFNAR2)+ NK cells, and the mean fluorescence intensity (MFI) of NK cell surface receptors IFNAR2 and NKp46 were detected.

RESULTS

66 patients were enrolled into the study in which 17 patients obtained functional cure. At baseline, hepatitis B virus desoxyribose nucleic acid (HBV DNA) titer in patients with functional cure was remarkably lower than that in Non-functional cure group. Compared with baseline, HBV DNA levels, HBsAg levels, and HBeAg levels significantly declined at week 12 and 24 of therapy in patients with functional cure. At baseline, the negative correlation between CD56bright NK% and HBV DNA and the negative correlation between CD56dim NK% and HBV DNA was showed; CD56bright NK% and IFNAR2 MFI in patients with functional cure were remarkably higher than those in patients without functional cure. After therapy, CD56bright NK% and NKp46high NK% in patients with functional cure were higher than those in patients without functional cure. In Functional cure group, after 24 weeks of treatment NK%, CD56bright NK%, IFNAR2 MFI weakly increased, and NKp46high NK% and NKp46 MFI significantly increased, meanwhile, CD56dim NK% and NKp46dim NK% decreased. Only NKp46 MFI increased after therapy in patients without functional cure.

CONCLUSION

The lower HBV DNA load and the higher CD56bright NK% before therapy, and the higher the post-treatment CD56bright NK%, IFNAR2 MFI, NKp46high NK%, the easier to achieve functional cure.

Hepatitis B functional cure and immune response

Hepatitis B virus (HBV) is a hepatotropic virus, which damage to hepatocytes is not direct, but through the immune system. HBV specific CD4+ T cells can induce HBV specific B cells and CD8+ T cells. HBV specific B cells produce antibodies to control HBV infection, while HBV specific CD8+ T cells destroy infected hepatocytes. One of the reasons for the chronicity of HBV infection is that it cannot effectively activate adoptive immunity and the function of virus specific immune cells is exhausted. Among them, virus antigens (including HBV surface antigen, e antigen, core antigen, etc.) can inhibit the function of immune cells and induce immune tolerance. Long term nucleos(t)ide analogues (NAs) treatment and inactive HBsAg carriers with low HBsAg level may "wake up" immune cells with abnormal function due to the decrease of viral antigen level in blood and liver, and the specific immune function of HBV will recover to a certain extent, thus becoming the "dominant population" for functional cure. In turn, the functional cure will further promote the recovery of HBV specific immune function, which is also the theoretical basis for complete cure of hepatitis B. In the future, the complete cure of chronic HBV infection must be the combination of three drugs: inhibiting virus replication, reducing surface antigen levels and specific immune regulation, among which specific immunotherapy is indispensable. Here we review the relationship, mechanism and clinical significance between the cure of hepatitis B and immune system.