Update on hepatitis B virus infection

Overview of chronic hepatitis B management

ABSTRACT

Chronic hepatitis B remains a substantial global health challenge, impacting approximately 254 million people worldwide. A cure for this condition is yet to be discovered. Early identification and effective treatments coupled with vigilant monitoring can help alleviate associated morbidity and mortality due to potential complications such as liver cirrhosis and hepatocellular carcinoma.

Combined model with acoustic radiation force impulse to rule out high-risk varices in HBV-related cirrhosis with viral suppression

AIMS

To prospectively evaluate the performance of spleen stiffness measurement (SSM) and liver stiffness measurement (LSM) via acoustic radiation force impulse (ARFI) imaging combined with platelet counts (PLT) in ruling out HRV in HBV-related cirrhotic patients with viral suppression.

METHODS

Patients with cirrhosis enrolled between June 2020-March 2022 were divided into a derivation cohort and validation cohort. LSM and SSM ARFI-based, and esophagogastroduodenoscopy (EGD) were performed at enrollment.

RESULTS

In the derivation cohort, overall, 236 HBV-related cirrhotic patients with maintained viral suppression were enrolled, and the prevalence of HRV was 19.5% (46/236). With the aim of identifying HRV, the most accurate LSM and SSM cut-offs were chosen of 1.46 m/s and 2.28 m/s, respectively. The combined model (LSM<1.46 m/s and PLT>150 × 109/L strategy combined with SSM ≤ 2.28 m/s) can spare 38.6% of EGDs and 4.3% of HRV cases were misclassified. In the validation cohort, we analysed 323 HBV-related cirrhotic patients with maintained viral suppression and validated the combined model can spare 33.4% (108/323) of EGD, and the HRV missed rate was 3.4%.

CONCLUSIONS

A non-invasive prediction model combining LSM<1.46 m/s and PLT>150 × 109/L strategy with SSM ≤ 2.28 m/s exhibited excellent performance in ruling out HRV and avoided a significantly large number (38.6% vs 33.4%) of unnecessary EGDs in HBV-related cirrhotic patients with viral suppression.

The Structural Diversity and Biological Activity of Steroid Oximes

Steroids and their derivatives have been the subject of extensive research among investigators due to their wide range of pharmacological properties, in which steroidal oximes are included. Oximes are a chemical group with the general formula R1R2C=N-OH and they exist as colorless crystals and are poorly soluble in water. Oximes can be easily obtained through the condensation of aldehydes or ketones with various amine derivatives, making them a very interesting chemical group in medicinal chemistry for the design of drugs as potential treatments for several diseases. In this review, we will focus on the different biological activities displayed by steroidal oximes such as anticancer, anti-inflammatory, antibacterial, antifungal and antiviral, among others, as well as their respective mechanisms of action. An overview of the chemistry of oximes will also be reported, and several steroidal oximes that are in clinical trials or already used as drugs are described. An extensive literature search was performed on three main databases-PubMed, Web of Science, and Google Scholar.

Switching from Tenofovir-Based Combination Therapy to Tenofovir Monotherapy in Multidrug-Experienced Chronic Hepatitis B Patients: a 5-Year Experience at Two Centers

Patients with chronic hepatitis B (CHB) who were administered tenofovir disoproxil fumarate (TDF)-based combination therapy after receiving multiple drugs are frequently switched to TDF monotherapy in South Korea. We evaluated the efficacy and safety of switching to TDF monotherapy from TDF-based combination therapy over 5 years. This was a retrospective study of multidrug-experienced CHB patients who switched from TDF-based combination therapy to TDF monotherapy after achieving a virologic response (VR; <20 IU/mL) at Konkuk University Hospital and Sanggye Paik Hospital. The biochemical response was defined as a normalized serum ALT level during follow-up. Each patient was assessed from the date of switching to TDF monotherapy to the date of the last follow-up over 5 years. A total of 39 patients who received at least one antiviral therapy before TDF-based combination therapy were analyzed. The median duration of VR before switching to TDF monotherapy was 18 months and the median duration of TDF monotherapy was 55 months. In this study, except for one patient who had poor compliance, all patients maintained a VR. Three patients had a temporarily increased HBV DNA level and 91.2% of the patients showed a biochemical response. Switching multidrug-experienced patients to TDF monotherapy is generally safe and effective.

Innate and adaptive immune escape mechanisms of hepatitis B virus

Chronic hepatitis B virus (HBV) infection is an international health problem with extremely high mortality and morbidity rates. Although current clinical chronic hepatitis B (CHB) treatment strategies can partly inhibit and eliminate HBV, viral breakthrough may result due to non-adherence to treatment, the emergence of viral resistance, and a long treatment cycle. Persistent CHB infection arises as a consequence of complex interactions between the virus and the host innate and adaptive immune systems. Therefore, understanding the immune escape mechanisms involved in persistent HBV infection is important for designing novel CHB treatment strategies to clear HBV and achieve long-lasting immune control. This review details the immunological and biological characteristics and escape mechanisms of HBV and the novel immune-based therapies that are currently used for treating HBV.

Identification and Characterization of Besifovir-Resistant Hepatitis B Virus Isolated from a Chronic Hepatitis B Patient

Hepatitis B virus (HBV) is known to cause severe liver diseases such as acute or chronic hepatitis, liver cirrhosis and hepatocellular carcinoma. Chronic hepatitis B (CHB) infection is a major health problem with nearly 300 million individuals infected worldwide. Currently, nucleos(t)ide analogs (NAs) and interferon alpha are clinically approved treatments for HBV infection. NAs are potent antiviral agents that bind to HBV polymerase and block viral reverse transcription and replication. Besifovir dipivoxil maleate (BSV) is a newly developed NA against HBV in the form of acyclic nucleotide phosphonate that is available for oral administration similar to adefovir and tenofovir. Until now, resistance to BSV treatment has not been reported. In this study, we found a CHB patient who showed viral breakthrough after long-term treatment with BSV. The isolated HBV DNA from patient’s serum were cloned into the replication-competent HBV 1.2 mer and the sequence of reverse transcriptase (RT) domain of HBV polymerase were analyzed. We also examined the drug susceptibility of generated clones in vitro. Several mutations were identified in HBV RT domain. A particular mutant harboring ten RT mutations showed resistance to BSV treatment in vitro. The ten mutations include rtV23I (I), rtH55R (R), rtY124H (H), rtD134E (E), rtN139K (K), rtL180M (M), rtM204V (V), rtQ267L (L), rtL269I (I) and rtL336M (M). To further identify the responsible mutations for BSV resistance, we performed in vitro drug susceptibility assay on several artificial clones. As a result, our study revealed that rtL180M (M) and rtM204V (V) mutations, already known as lamivudine-resistant mutations, confer resistance to BSV in the CHB patient.

Critical Updates on Chronic Hepatitis B Virus Infection in 2021

Chronic hepatitis B virus (HBV) infection is a global healthcare burden in the form of chronic liver disease, cirrhosis, liver failure and liver cancer. There is no definite cure for the virus and even though extensive vaccination programs have reduced the burden of liver disease in the future population, treatment options to eradicate the virus from the host are still lacking. In this review, we discuss in detail current updates on the structure and applied biology of the virus in the host, examine updates to current treatment and explore novel and state-of-the-art therapeutics in the pipeline for management of chronic HBV. Furthermore, we also specifically review clinical updates on HBV-related acute on chronic liver failure (ACLF). Current treatments for chronic HBV infection have seen important updates in the form of considerations for treating patients in the immune tolerant phase and some clarity on end points for treatment and decisions on finite therapy with nucleos(t)ide inhibitors. Ongoing cutting-edge research on HBV biology has helped us identify novel target areas in the life cycle of the virus for application of new therapeutics. Due to improvements in the area of genomics, the hope for therapeutic vaccines, vector-based treatments and focused management aimed at targeting host integration of the virus and thereby a total cure could become a reality in the near future. Newer clinical prognostic tools have improved our understanding of timing of specific treatment options for the catastrophic syndrome of ACLF secondary to reactivation of HBV. In this review, we discuss in detail pertinent updates regarding virus biology and novel therapeutic targets with special focus on the appraisal of prognostic scores and treatment options in HBV-related ACLF.

Comparison of two-dimensional shear wave elastography, magnetic resonance elastography, and three serum markers for diagnosing fibrosis in patients with chronic hepatitis B: a meta-analysis

BACKGROUND

Two-dimensional shear wave elastography (2D-SWE), magnetic resonance elastography (MRE), aspartate transaminase-to-platelet ratio index (APRI), fibrosis index based on 4 factors (FIB-4), and King's score have been proposed for diagnosing fibrosis.

METHODS

Literature databases were searched until October 1st, 2020. The summary area under the receiver operating characteristic curve (AUROC), the summary diagnostic odds ratios, and the summary sensitivities and specificities were used to assess the performance of these noninvasive methods for staging fibrosis.

RESULTS

Our final data contained 72 studies. The prevalence of significant fibrosis, advanced fibrosis, and cirrhosis was 58.3%, 36.2%, and 20.5%, respectively, in chronic hepatitis B (CHB). For 2D-SWE and MRE, the summary AUROCs were 0.89 and 0.97, 0.95 and 0.97, and 0.94 and 0.97 for significant fibrosis, advanced fibrosis, and cirrhosis, respectively. The summary AUROCs using APRI and FIB-4 for detecting significant fibrosis, advanced fibrosis, and cirrhosis were 0.76 and 0.75, 0.74 and 0.77, and 0.77 and 0.82, respectively. The summary AUROCs of King's score for detecting significant fibrosis and cirrhosis were 0.77 and 0.83, respectively.

CONCLUSION

MRE and 2D-SWE may show the best diagnostic accuracy for predicting fibrosis in CHB. Among the three serum markers, King's score may be more useful for diagnosing fibrosis.

Interaction analysis of gene variants related to one-carbon metabolism with chronic hepatitis B infection in Chinese patients

BACKGROUND

The risk of chronic hepatitis B (CHB) infection is influenced by aberrant DNA methylation and altered nucleotide synthesis and repair, possibly caused by polymorphic variants in one-carbon metabolism genes. In the present study, we investigated the relationship between polymorphisms belonging to the one-carbon metabolic pathway and CHB infection.

METHODS

A case-control study using 230 CHB patients and 234 unrelated healthy controls was carried out to assess the genetic association of 24 single nucleotide polymorphisins (SNPs) determined by mass spectrometry.

RESULTS

Three SNPs, comprising rs10717122 and rs2229717 in serine hydroxymethyltransferase1/2 (SHMT2) and rs585800 in betaine-homocysteine S-methyltransferase (BHMT), were associated with the risk of CHB. Patients with DEL allele, DEL.DEL and DEL.T genotypes of rs10717122 had a 1.40-, 2.00- and 1.83-fold increased risk for CHB, respectively. Cases inheriting TA genotype of rs585800 had a 2.19-fold risk for CHB infection. The T allele of rs2229717 was less represented in the CHB cases (odds ratio = 0.66, 95% confidence interval = 0.48-0.92). The T allele of rs2229717 was less in patients with a low hepatitis B virus-DNA level compared to the control group (odds ratio = 0.49, 95% confidence interval = 0.25-0.97) and TT genotype of rs2229717 had a significant correlation with hepatitis B surface antigen level (p = 0.0195). Further gene-gene interaction analysis showed that subjects carrying the rs10717122 DEL.DEL/DEL.T and rs585800 TT/TA genotypes had a 2.74-fold increased risk of CHB.

CONCLUSIONS

The results of the present study suggest that rs10717122, rs585800 and rs2229717 and gene-gene interactions of rs10717122 and rs585800 affect the outcome of CHB infection, at the same time as indicating their usefulness as a predictive and diagnostic biomarker of CHB infection.

Bile Acids Impair Vaccine Response in Children With Biliary Atresia

Background

Vaccination is the best way to protect children under 5 years from death or disability. Children with biliary atresia (BA), which is the most common pediatric cholestatic end-stage liver disease (PELD), are more vulnerable to infectious diseases. However, the vaccination coverage and factors modulating vaccine responses in children with BA are largely unknown.

Methods

In this study, 288 children (median age: 7 months) diagnosed with BA before liver transplantation were enrolled for the evaluation of vaccination status and the factors affecting the immune response to the hepatitis B (HBV) vaccine. Moreover, 49 BA children (median age: 4 months) were enrolled for flow cytometric analysis of CD4⁺ T cells and CD19⁺ B cell subsets and correlations with serum bile acid levels.

Results

Generally, these children had very low routine vaccination rates for the meningococcal serogroup AC (Men AC) (41.2%), measles-mumps-rubella (MMR) (31.3%), poliomyelitis (Polio) (25.3%), hepatitis A (HAV) (25.0%), Japanese encephalitis (JE) (15.0%), diphtheria-tetanus-pertussis (DTP) (14.2%), meningococcal serogroup A (Men A) (13.5%) and varicella (VAR) (10.8%) vaccines, but not for the HBV (96.2%) and bacillus Calmette-Guérin (BCG) (84.7%) vaccines. Remarkably, 19.8% (57/288) of the patients had HBV infection. Out of 220 patients vaccinated for HBV, 113 (51.4%), 85 (38.6%) and 22 (10%) had one, two or three doses of the HBV vaccine, respectively. Furthermore, logistic regression analysis revealed that the bile acid level was an independent factor associated with poor HBV vaccine response (p = 0.03; OR = 0.394; 95% CI = 0.170-0.969). Immunophenotyping showed that bile acids were only negatively correlated with the CD19⁺CD27⁺IgG⁺ post-class-switched memory B cell ratio (p = 0.01).

Conclusion

This study reveals the overall vaccination rates of routine vaccines in Chinese BA children are very low and the poor HBV vaccine responses are associated with bile acids, possibly via the inhibition of CD19⁺CD27⁺IgG⁺ post-class-switched memory B cell response.

Clinical Trial Registration

http://www.chictr.org.cn, identifier ChiCTR1800019165.

Normal values of combinational elastography in adult liver: the influence of age

PURPOSE

We aimed to clarify the normal values obtained by simultaneous use of shear wave imaging and strain imaging (combinational elastography) in liver and reveal how aging influences them.

METHODS

In our checkup center, 257 examinees were diagnosed with normal liver based on questionnaires about liver disease and their drinking history, liver function test results, and ultrasound B-mode study findings. We estimated the values of combinational elastography and considered the correlation between the values and age. A multivariate analysis was performed concerning several features and the liver fibrosis (LF) index. We divided examinees into a younger group (< 65 years old) and an older group (≥ 65 years old), and assessed the effect of age on the LF index.

RESULTS

The mean shear wave velocity (Vs) of shear wave measurement (SWM) was 1.10 ± 0.17 m/s (range 0.84-1.93), and the mean LF index of real-time tissue elastography (RTE) was 1.371 ± 0.458 (range 0.258-3.173). There was no significant correlation between Vs and age. However, the LF index increased significantly with age. The multivariate analysis showed that age (P < 0.001) and BMI (P < 0.05) significantly affected the LF index. Indeed, the LF index in the older group was significantly higher than that in the younger group (P < 0.001).

CONCLUSION

In adult liver, the normal Vs of SWM was 1.10 ± 0.17 m/s, and the normal LF index of RTE was 1.371 ± 0.458. The LF index increased significantly with age in contrast to Vs; therefore, the influence of age should be considered when using combinational elastography.

Baveno VI criteria and spleen stiffness measurement rule out high-risk varices in virally suppressed HBV-related cirrhosis

BACKGROUND & AIMS

There are no data validating the performance of spleen stiffness measurement in ruling out high-risk varices in patients with HBV-related cirrhosis under maintained viral suppression. Thus, we aimed to prospectively validate the performance of spleen stiffness measurement (cut-off 46 kPa) combined with Baveno VI criteria in ruling out high-risk varices in these patients.

METHODS

Patients with cirrhosis were enrolled from April to December 2019 at the hepatology unit of the Nanfang Hospital, China. Liver and spleen transient elastography and esophagogastroduodenoscopy were performed at enrollment. Antiviral regimen(s) and virological responses, evaluated every 3-6 months, were recorded.

RESULTS

Overall 341 patients with HBV-related cirrhosis under maintained viral suppression were enrolled, and the prevalence of high-risk varices was 20.5% (70/341). Baveno VI criteria spared 37.0% (126/341) esophagogastroduodenoscopies and no high-risk varices were missed (0/70). Eight cases of high-risk varices (8/70, 11.4%) were misclassified in patients (208/341, 61.0%) within the expanded Baveno VI criteria. The spleen stiffness measurement cut-off (≤46.0 kPa) was shown to safely rule out high-risk varices in these patients (the percentage of missed high-risk varices was 4.3%). Over half (61.6%, 210/341) of patients met the combined model (Baveno VI criteria and spleen stiffness measurement cut-off ≤46 kPa) and 4.3% (3/70) of high-risk varices cases were misclassified. This combined model exhibited a sensitivity of 95.71%, specificity of 76.38%, negative predictive value of 98.57%, and negative likelihood ratio of 0.06 for ruling out high-risk varices.

CONCLUSIONS

We validated the excellent performance of Baveno VI criteria combined with spleen stiffness measurement (cut-off 46 kPa) for safely ruling out high-risk varices in patients with HBV-related cirrhosis under viral suppression; more than half of esophagogastroduodenoscopy procedures were spared using this combination.

CLINICAL TRIAL NUMBER

NCT04123509 LAY SUMMARY: Esophageal varices have important prognostic implications in patients with cirrhosis. Thus, their timely identification is important so that treatment can be initiated early. Herein, we validated the excellent performance of the combination of Baveno VI criteria with spleen stiffness measurement (cut-off 46 kPa) for ruling out high-risk esophageal varices in patients with HBV-related cirrhosis under maintained viral suppression (with antiviral treatment). This combined model was able to safely rule out high-risk varices (missed/total <5%) and over half (61.6%) of esophagogastroduodenoscopy procedures were spared.

Curcumin and Photobiomodulation in Chronic Viral Hepatitis and Hepatocellular Carcinoma

Immune modulation is a very modern medical field for targeting viral infections. In the race to develop the best immune modulator against viruses, curcumin, as a natural product, is inexpensive, without side effects, and can stimulate very well certain areas of the human immune system. As a bright yellow component of turmeric spice, curcumin has been the subject of thousands of scientific and clinical studies in recent decades to prove its powerful antioxidant properties and anticancer effects. Curcumin has been shown to influence inter- and intracellular signaling pathways, with direct effects on gene expression of the antioxidant proteins and those that regulate the immunity. Experimental studies have shown that curcumin modulates several enzyme systems, reduces nitrosative stress, increases the antioxidant capacity, and decreases the lipid peroxidation, protecting against fatty liver pathogenesis and fibrotic changes. Hepatitis B virus (HBV) affects millions of people worldwide, having sometimes a dramatic evolution to chronic aggressive infection, cirrhosis, and hepatocellular carcinoma. All up-to-date treatments are limited, there is still a gap in the scientific knowledge, and a sterilization cure may not yet be possible with the removal of both covalently closed circular DNA (cccDNA) and the embedded HBV DNA. With a maximum light absorption at 420 nm, the cytotoxicity of curcumin as photosensitizer could be expanded by the intravenous blue laser blood irradiation (IVBLBI) or photobiomodulation in patients with chronic hepatitis B infection, Hepatitis B e-antigen (HBeAg)-positive, noncirrhotic, but nonresponsive to classical therapy. Photobiomodulation increases DNA repair by the biosynthesis of complex molecules with antioxidant properties, the outset of repairing enzyme systems and new phospholipids for regenerating the cell membranes. UltraBioavailable Curcumin and blue laser photobiomodulation could suppress the virus and control better the disease by reducing inflammation/fibrosis and stopping the progression of chronic hepatitis, reversing fibrosis, and diminishing the progression of cirrhosis, and decreasing the incidence of hepatocellular carcinoma. Photodynamic therapy with blue light and curcumin opens new avenues for the effective prevention and cure of chronic liver infections and hepatocellular carcinoma. Blue laser light and UltraBioavailable Curcumin could be a new valuable alternative for medical applications in chronic B viral hepatitis and hepatocarcinoma, saving millions of lives.

Potential Drug Targets Against Hepatitis B Virus Based on Both Virus and Host Factors

BACKGROUND

Hepatitis B is a very harmful and epidemic disease caused by hepatitis B virus (HBV). Although an effective anti-HBV vaccine is available, chronic infection poses still a huge health burden in the whole world. The present anti-HBV drugs including nucleoside analogues and interferonalpha have their limitations without exception. There is no effective drug and therapeutic method that can really and truly cure hepatitis B so far. The variability of HBV genome results in that a significant number of patients develop drug resistance during the long-term use of anti-HBV drugs. Hence, it is urgently needed to discover novel targets and develop new drugs against hepatitis B.

OBJECTIVE

The review aims to provide the theory support for designing of the anti-HBV innovative drugs by offering a summary of the current situation of antiviral potential targets.

RESULTS AND CONCLUSION

Since HBV is obligate intracellular parasite, and as such it depends on host cellular components and functions to replicate itself. The targeting both virus and host might be a novel therapeutic option for hepatitis B. Accordingly, we analyse the advances in the study of the potential drug targets for anti-HBV infection, focusing on targeting virus genome, on targeting host cellular functions and on targeting virus-host proteins interactions, respectively. Meanwhile, the immune targets against chronic hepatitis B are also emphasized. In short, the review provides a summary of antiviral therapeutic strategies to target virus factors, host factors and immune factors for future designing of the innovative drug against HBV infection.

Discovery and optimizing polycyclic pyridone compounds as anti-HBV agents

INTRODUCTION

Hepatitis B disease is caused by the hepatitis B virus (HBV), which is a DNA virus that belongs to the Hepadnaviridae family. It is a considerable health burden, with 257 million active cases globally. Long-standing infection may create a fundamental cause of liver disease and chronic infections, including cirrhosis, hepatocellular, and carcinoma liver failure. There is an urgent need to develop novel, safe, and effective drug candidates with a novel mechanism of action, improved activity, efficacy, and cure rate.

AREAS COVERED

Herein, the authors provide a concise report focusing on a general and cutting-edge overview of the current state of polycyclic pyridone-related anti-HBV agent patents from 2016 to 2018 and some future perspectives.

EXPERT OPINION

In medicinal chemistry, high-throughput screening (HTS), hit-to-lead optimization (H2L), bioisosteric replacement, and scaffold hopping approaches are playing a major role in the discovery and development of HBV inhibitors. Developing polycyclic pyridone-related anti-HBV agents that could target host factors has attracted significant interest and attention in recent years.

Design, Synthesis and Bioactive Evaluation of Oxime Derivatives of Dehydrocholic Acid as Anti-Hepatitis B Virus Agents

Oxime derivatives of dehydrocholic acid and its esters were designed for anti-hepatitis B virus (HBV) drugs according to principles of assembling active chemical fragments. Twelve compounds were synthesized from dehydrocholic acid by esterification and oxime formation, and their anti-hepatitis B virus (HBV) activities were evaluated with HepG 2.2.15 cells. Results showed that 5 compounds exhibited more effective inhibition of HBeAg than positive control, among them 2b-3 and 2b-1 showed significant anti-HBV activities on inhibiting secretion of HBeAg (IC_{50 (2b-3)} = 49.39 ± 12.78 μM, SI _(2b-3) = 11.03; IC_{50 (2b-1)} = 96.64 ± 28.99 μM, SI _(2b-1) = 10.35) compared to the Entecavir (IC₅₀ = 161.24 μM, SI = 3.72). Molecular docking studies showed that most of these compounds interacted with protein residues of heparan sulfate proteoglycan (HSPG) in host hepatocyte and bile acid receptor.

Viral Hepatitis and Iron Dysregulation: Molecular Pathways and the Role of Lactoferrin

The liver is a frontline immune site specifically designed to check and detect potential pathogens from the bloodstream to maintain a general state of immune hyporesponsiveness. One of the main functions of the liver is the regulation of iron homeostasis. The liver detects changes in systemic iron requirements and can regulate its concentration. Pathological states lead to the dysregulation of iron homeostasis which, in turn, can promote infectious and inflammatory processes. In this context, hepatic viruses deviate hepatocytes' iron metabolism in order to better replicate. Indeed, some viruses are able to alter the expression of iron-related proteins or exploit host receptors to enter inside host cells. Lactoferrin (Lf), a multifunctional iron-binding glycoprotein belonging to the innate immunity, is endowed with potent antiviral activity, mainly related to its ability to block viral entry into host cells by interacting with viral and/or cell surface receptors. Moreover, Lf can act as an iron scavenger by both direct iron-chelation or the modulation of the main iron-related proteins. In this review, the complex interplay between viral hepatitis, iron homeostasis, and inflammation as well as the role of Lf are outlined.

Add-on pegylated interferon augments hepatitis B surface antigen clearance vs continuous nucleos(t)ide analog monotherapy in Chinese patients with chronic hepatitis B and hepatitis B surface antigen ≤ 1500 IU/mL: An observational study

BACKGROUND

Nucleos(t)ide analog (NA) has shown limited effectiveness against hepatitis B surface antigen (HBsAg) clearance in chronic hepatitis B (CHB) patients.

AIM

To evaluate the efficacy and safety of add-on peginterferon α-2a (peg-IFN α-2a) to an ongoing NA regimen in CHB patients.

METHODS

In this observational study, 195 CHB patients with HBsAg ≤ 1500 IU/mL, hepatitis B e antigen (HBeAg)-negative (including HBeAg-negative patients or HBeAg-positive patients who achieved HBeAg-negative after antiviral treatment with NA) and hepatitis B virus-deoxyribonucleic acid < 1.0 × 102 IU/mL after over 1 year of NA therapy were enrolled between November 2015 and December 2018 at the Second Affiliated Hospital of Xi'an Jiaotong University, China. Patients were given the choice between receiving either peg-IFN α-2a add-on therapy to an ongoing NA regimen (add-on group, n = 91) or continuous NA monotherapy (monotherapy group, n = 104) after being informed of the benefits and risks of the peg-IFN α-2a therapy. Total therapy duration of peg-IFN α-2a was 48 wk. All patients were followed-up to week 72 (24 wk after discontinuation of peg-IFN α-2a). The primary endpoint was the proportion of patients with HBsAg clearance at week 72.

RESULTS

Demographic and baseline characteristics were comparable between the two groups. Intention-to-treatment analysis showed that the HBsAg clearance rate in the add-on group and monotherapy group was 37.4% (34/91) and 1.9% (2/104) at week 72, respectively. The HBsAg seroconversion rate in the add-on group was 29.7% (27/91) at week 72, and no patient in the monotherapy group achieved HBsAg seroconversion at week 72. The HBsAg clearance and seroconversion rates in the add-on group were significantly higher than in the monotherapy group at week 72 (P < 0.001). Younger patients, lower baseline HBsAg concentration, lower HBsAg concentrations at weeks 12 and 24, greater HBsAg decline from baseline to weeks 12 and 24 and the alanine aminotransferase ≥ 2 × upper limit of normal during the first 12 wk of therapy were strong predictors of HBsAg clearance in patients with peg-IFN α-2a add-on treatment. Regarding the safety of the treatment, 4.4% (4/91) of patients in the add-on group discontinued peg-IFN α-2a due to adverse events. No severe adverse events were noted.

CONCLUSION

Peg-IFN α-2a as an add-on therapy augments HBsAg clearance in HBeAg-negative CHB patients with HBsAg ≤ 1500 IU/mL after over 1 year of NA therapy.

Patients with suboptimal hepatitis B virus diagnostic characterization are at risk of liver fibrosis progression

BACKGROUND

Many patients with chronic hepatitis B virus infection remain infradiagnosed and untreated. In a national health system with unrestricted access to treatment, our aims were to assess the level of compliance with clinical guidelines and the characteristics and risk of fibrosis progression in patients with suboptimal diagnosis.

METHODS

In a cohort of patients with positive hepatitis B surface antigen from January 2011 to December 2013, data were registered to assess characteristics and compliance with guidelines. For assessing the risk of liver fibrosis, positive hepatitis B surface antigen patients from January 2008 to December 2013 were grouped depending on DNA request. Liver fibrosis was estimated by serological scores.

RESULTS

Of 41 158 subjects with hepatitis B surface antigen request, 351 (0.9%) tested positive, and DNA was not available from 110 patients (66.4% male, mean 42.4 ± 14.5 years) after a median of 25.6 months (range 12.0-43.5). Most of these patients (76%) were assessed by primary care. Half of the patients (47.2%) showed hypertransaminasemia, at least significant fibrosis, or both conditions. After long follow-up (mean 90.1 ± 45.2 months), these patients had a higher risk of achieving at least significant fibrosis during follow-up (log-rank 8.73; P = 0.003).

CONCLUSION

In more than one-third of patients with positive hepatitis B surface antigen, DNA was not requested despite showing hypertransaminasemia and significant fibrosis. Patients without DNA request are at high risk of liver fibrosis progression. Thus, educational measures and other strategies are necessary, especially targeting primary care, to improve access to treatment.

The significance of IL-28B and CK-18 M30 levels in the diagnosis of non-alcoholic steatohepatitis in SD rats

AIMS

To investigate the role of IL-28B and CK-18 M30 in the diagnosis of non-alcoholic steatohepatitis (NASH) in rats.

METHODS

The rat NASH model was constructed by high-fat diet feeding and confirmed by liver tissue pathology analysis. The CK-18 M30, IL-28B, liver function and blood lipid were detected. The pathology of liver tissues was observed by H&E staining. The ROC curves of liver pathological scores, IL-28B, and CK-18 M30 were plotted and the sensitivity/specificity of each index was calculated.

RESULTS

The liver tissue pathology at the end of the 12th week met NASH diagnostic criteria. The liver pathological scores of NASH model were higher than those of the control group (P < 0.05). Compared with the control group, the body weight of rats in the NASH group was lower (P < 0.05) and the liver index was higher (P < 0.05). Moreover, the serum levels of alanine aminotransferase, triglyceride, low-density lipoprotein, total cholesterol and CK-18 M30 in the NASH group were higher (P < 0.05) and positively correlated with liver pathological scores (P < 0.05), but IL-28B in serum and liver tissue was lower (P < 0.05) and negatively correlated with liver pathological scores (P < 0.05). According to the ROC curves, the sensitivity/specificity of each index was shown as following: liver pathological scores (1.000/1.000), IL-28B of liver tissue (1.000/0.857), serum CK-18 M30 plus IL-28B (0.857/1.000), serum IL-28B (0.857/0.857) and serum CK-18 M30 (1.000/0.857).

CONCLUSIONS

IL-28B level is related to the pathological changes of livers in SD rats during the development of NASH. The combination of serum CK-18 M30 level and serum IL-28B level may be a promising non-invasive detection method for the diagnosis of NASH.

Comprehensive Analysis of the mRNA-lncRNA Co-expression Profile and ceRNA Networks Patterns in Chronic Hepatitis B

Background:

Long non-coding RNAs (lncRNAs) are emerging as important regulators in the modulation of virus infection by targeting mRNA transcription. However, their roles in chronic hepatitis B (CHB) remain to be elucidated.

Objective:

The study aimed to explore the lncRNAs and mRNA expression profiles in CHB and asymp-tomatic HBsAg carriers (ASC) and construct mRNA-lncRNA co-expression profile and ceRNA net-works to identify the potential targets of diagnosis and treatment in CHB.

Methods:

We determined the expression profiles of lncRNAs and mRNAs in CHB and ASC using mi-croarray analysis. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) path-way enrichment analyses were performed to explore their function. We also constructed co-expression, cis-regulatory, and competing endogenous RNA (ceRNA) networks with bioinformatics methods.

Results:

We identified 1634 mRNAs and 5550 lncRNAs that were differentially expressed between CHB and ASC. Significantly enriched GO terms and pathways were identified, many of which were linked to immune processes and inflammatory responses. Co-expression analysis showed 1196 relation-ships between the top 20 up/downregulated lncRNAs and mRNA, especially 213 lncRNAs interacted with ZFP57. The ZFP57-specific ceRNA network covered 3 lncRNAs, 5 miRNAs, and 17 edges. Cis-correlation analysis showed that lncRNA T039096 was paired with the most differentially expressed gene, ZFP57. Moreover, by expending the clinical samples size, the qRT-PCR results showed that the expression of ZFP57 and T039096 increased in CHB compared to ASC.

Conclusion:

Our study provides insights into the roles of mRNA and lncRNA networks in CHB, high-lighting potential applications of lncRNA-T039096 and mRNA-ZFP57 for diagnosis and treatment.

Association between host TNF-α, TGF-β1, p53 polymorphisms, HBV X gene mutation, HBV viral load and the progression of HBV-associated chronic liver disease in Indonesian patients

In developing countries, including Indonesia, there is a high mortality rate associated with the progression of hepatitis B virus (HBV)-associated chronic liver disease (CLD). The pathogenesis of HBV infection is influenced by viral and host factors. To determine potential associations between these factors, host single nucleotide polymorphisms (SNPs) on TNF-α, TGF-β1 and p53, HBV X gene mutation and HBV viral load were investigated in patients with HBV-associated CLD in Surabaya, Indonesia. Sera were collected from 87 CLD patients with HBV infection. TNF-α, TGF-β1 and p53 SNPs were genotyped by PCR restriction fragment length polymorphism. The HBV X gene was sequenced and compared with reference strains to determine mutations and the viral load was measured using reverse transcription-quantitative PCR. In Indonesian patients, no association between TNF-α, TGF-β1 and p53 SNPs and CLD or X gene mutation were identified. A total of 23% (20/87) of samples had HBV X gene mutations, including ten substitution types, one deletion and one insertion. Multinomial regression analysis revealed that the K130M/V131I mutations were correlated with CLD progression (OR, 7.629; 95% CI, 1.578-36.884). Significant differences in viral load were found in HBV-infected patients who had X gene mutations, such as R87W/G, I127L/T/N/S and K130M/V131I mutations (P<0.05). The presence of K130M and V131I mutations may be predictive for the progression of HBV-associated CLD in Indonesia.

Impact of RNA Virus Evolution on Quasispecies Formation and Virulence

RNA viruses are known to replicate by low fidelity polymerases and have high mutation rates whereby the resulting virus population tends to exist as a distribution of mutants. In this review, we aim to explore how genetic events such as spontaneous mutations could alter the genomic organization of RNA viruses in such a way that they impact virus replications and plaque morphology. The phenomenon of quasispecies within a viral population is also discussed to reflect virulence and its implications for RNA viruses. An understanding of how such events occur will provide further evidence about whether there are molecular determinants for plaque morphology of RNA viruses or whether different plaque phenotypes arise due to the presence of quasispecies within a population. Ultimately this review gives an insight into whether the intrinsically high error rates due to the low fidelity of RNA polymerases is responsible for the variation in plaque morphology and diversity in virulence. This can be a useful tool in characterizing mechanisms that facilitate virus adaptation and evolution.

Ex vivo Detection and Characterization of Hepatitis B Virus-Specific CD8+ T Cells in Patients Considered Immune Tolerant

In this study, we aimed to detect and characterize ex vivo virus-specific CD8+ T cells in patients with immune-tolerant hepatitis B virus (HBV) infection. We investigated a Korean chronic hepatitis B cohort composed of 15 patients in the immune-tolerant phase, 17 in the immune-active phase, and 13 under antiviral treatment. We performed enzyme-linked immunospot (ELISpot) assays ex vivo and intracellular cytokine staining after in vitro culture. We also performed ex vivo multimer staining assays and examined the expression of programmed death-1 (PD-1) and CD127 in pentamer-positive cells. Ex vivo ELISpot revealed that HBV-specific T cell function was weaker in immune-tolerant patients than in those under antiviral treatment. In vitro culture of peripheral blood mononuclear cells for 10 days revealed that HBV-specific CD8+ T cells produced interferon-γ in some immune-tolerant patients. We detected HBV-specific CD8+ T cells ex vivo (using the HBV core18-27 pentamer) in patients from all three groups. The PD-1+ subset of pentamer+ CD8+ T cells was smaller ex vivo in the immune-tolerant phase than in the immune-active phase or under antiviral treatment. Interestingly, the proportion of PD-1+ CD8+ T cells in HBV-specific CD8+ T cells correlated with patient age when all enrolled patients were analyzed. Overall, HBV-specific CD8+ T cells are present in patients considered as immune-tolerant, although their ex vivo functionality is significantly weaker than that in patients under antiviral treatment (P < 0.05). Despite the high viral load, the proportion of PD-1 expression in HBV-specific CD8+ T cells is lower in the immune-tolerant phase than in other phases. Our results indicate appropriate stimulation may enhance the effector function of HBV-specific CD8+ T cells in patients considered as being in the immune-tolerant phase.

Novel Hepatitis B Virus Capsid-Targeting Antiviral That Aggregates Core Particles and Inhibits Nuclear Entry of Viral Cores

An estimated 240 million are chronically infected with hepatitis B virus (HBV), which can lead to liver disease, cirrhosis, and hepatocellular carcinoma. Currently, HBV treatment options include only nucleoside reverse transcriptase inhibitors and the immunomodulatory agent interferon alpha, and these treatments are generally not curative. New treatments with novel mechanisms of action, therefore, are highly desired for HBV therapy. The viral core protein (Cp) has gained attention as a possible therapeutic target because of its vital roles in the HBV life cycle. Several classes of capsid assembly effectors (CAEs) have been described in detail, and these compounds all increase capsid assembly rate but inhibit HBV replication by different mechanisms. In this study, we have developed a thermal shift-based screening method for CAE discovery and characterization, filling a much-needed gap in high-throughput screening methods for capsid-targeting molecules. Using this approach followed by cell-based screening, we identified the compound HF9C6 as a CAE with low micromolar potency against HBV replication. HF9C6 caused large multicapsid aggregates when capsids were assembled in vitro and analyzed by transmission electron microscopy. Interestingly, when HBV-expressing cells were treated with HF9C6, Cp was excluded from cell nuclei, suggesting that this compound may inhibit nuclear entry of Cp and capsids. Furthermore, mutational scanning of Cp suggested that HF9C6 binds the known CAE binding pocket, indicating that key Cp-compound interactions within this pocket have a role in determining the CAE mechanism of action.

Sustained serological and complete responses in HBeAg-positive patients treated with Peginterferon alfa-2b: a 6-year long-term follow-up of a multicenter, randomized, controlled trial in China

BACKGROUND

Pegylated interferon (PEG-IFN) alfa-2b is recommended for chronic hepatitis B (CHB). We aimed to investigate the sustainability of off-treatment responses among Chinese HBeAg-positive CHB patients treated with PEG-IFN alfa-2b from a randomized trial.

METHODS

Eligible Chinese patients (n = 322) were followed up by one visit after a median of 6 years (LTFU) following their participation in a randomized trial evaluating the efficacy of three PEG-IFN alfa-2b dosing regimens (1.0 or 1.5 μg/kg/wk. 24 weeks or 1.5 μg/kg/wk. 48 weeks). Primary endpoints at the LTFU were sustained SR and CR (SR/CR at the end of original study [EOS] and at the LTFU). SR was defined as HBeAg loss and seroconversion to anti-HBe and CR as HBeAg loss and seroconversion to anti-HBe and HBV-DNA < 2000 IU/mL.

RESULTS

The proportions of patients achieving sustained SR among patients who had SR at EOS were high in three treatment groups (61.9, 65.5, 76.5%, respectively, p = 0.46); treatment with PEG-IFN alfa-2b 1.5 μg/kg/wk. 48 weeks had the highest proportion of a sustained CR among patients who had CR at EOS (75.0%, p = 0.05). A considerable number of patients achieved sustained SR (18.2-29.9%) and sustained CR (14.8-18.3%) after EOS despite no further NA treatment. At the LTFU, rates of SR and CR were less than 70.0 and 50.0%, respectively, among all enrolled patients regardless of additional nucleos(t)ide analogs before the LTFU.

CONCLUSIONS

PEG IFN alfa-2b therapy had considerable off-treatment sustainability in Chinese HBeAg positive chronic hepatitis B patients with serological and complete responses.

Evaluation of single nucleotide polymorphism in interleukin 22 (IL-22) gene and its association with chronic hepatitis B infection

AIM

This study aimed to evaluate rs1179251 single nucleotide polymorphism in the IL-22 gene as a host factor and its effect on chronic hepatitis B infection.

BACKGROUND

Interleukin 22 (IL-22) belongs to a group of recently discovered cytokines, and it is produced and secreted by innate lymphoid cells (ILCs) and T helper 22 (Th22) cells. This cytokine plays dual roles as pro-inflammatory and anti-inflammatory effects in various conditions and different tissues of the body.

METHODS

This study was performed based on a case-control format to assess IL-22 rs1179251 single nucleotide polymorphism genotypic and allelic frequencies among 227 hepatitis B chronic patients and 227 healthy controls. The polymerase chain reaction and restriction fragment length polymorphism techniques were employed to determine the polymorphism's genotypes.

RESULTS

Genotypes Frequencies in patients' group were determined CC 59.91%, CG 37.89%, and GG 2.20% respectively in comparison to CC 63.44%, CG 31.72% and GG 4.85% in control group. The findings revealed that there was no statistically significant difference in the genotypes (P=0.156) frequencies of IL-22 gene polymorphism (rs1179251) between patients and control groups.

CONCLUSION

No association was found between rs1179251 single nucleotide polymorphism in IL-22 gene and chronic hepatitis B infection. So, in spite of the importance of IL-22 gene in immune responses, the studied polymorphism does not serve a decisive role in susceptibility to hepatitis B virus chronic infection.

Molecular Techniques for Blood and Blood Product Screening

Blood product safety is a high priority for manufacturing industries, hospitals, and regulatory agencies. An important step in ensuring safety is the screening of donated blood for infectious diseases. Molecular technologies for screening infectious diseases have improved remarkably over the years. Molecular biological assay significantly reduced the risk of transfusion-transmitted infections. Unlike previous methods, molecular technologies for screening infectious diseases are specific, efficient, easy to use, and economical. A new era in molecular biology is coming to the field of blood safety.

Autoimmune Kidney Diseases Associated with Chronic Viral Infections

Autoimmune kidney diseases triggered by viruses are an important cause of kidney disease in patients affected by chronic viral infection. Hepatitis B virus (HBV) infection is associated with membranous nephropathy and polyarteritis nodosa. Hepatitis C virus (HCV) infection is a major cause of cryoglobulinemic glomerulonephritis. Patients with human immunodeficiency virus (HIV) may develop HIV-associated nephropathy, a form of collapsing focal segmental glomerulosclerosis, or various forms of immune-complex-mediated kidney diseases. This article summarizes what is known about the pathogenesis, diagnosis, and management of immune-mediated kidney diseases in adults with chronic HBV, HCV, and HIV infections.

Hepatitis B virus infection

Hepatitis B virus (HBV) is a hepatotropic virus that can establish a persistent and chronic infection in humans through immune anergy. Currently, 3.5% of the global population is chronically infected with HBV, although the incidence of HBV infections is decreasing owing to vaccination and, to a lesser extent, the use of antiviral therapy to reduce the viral load of chronically infected individuals. The course of chronic HBV infection typically comprises different clinical phases, each of which potentially lasts for decades. Well-defined and verified serum and liver biopsy diagnostic markers enable the assessment of disease severity, viral replication status, patient risk stratification and treatment decisions. Current therapy includes antiviral agents that directly act on viral replication and immunomodulators, such as interferon therapy. Antiviral agents for HBV include reverse transcriptase inhibitors, which are nucleoside or nucleotide analogues that can profoundly suppress HBV replication but require long-term maintenance therapy. Novel compounds are being actively investigated to achieve the goal of HBV surface antigen seroclearance (functional cure), a serological state that is associated with a higher remission rate (thus, no viral rebound) after treatment cessation and a lower rate of cirrhosis and hepatocellular carcinoma. This Primer addresses several aspects of HBV infection, including epidemiology, immune pathophysiology, diagnosis, prevention and management.

Diagnosis and Assessment of Microbial Infections with Host and Microbial MicroRNA Profiles

MicroRNAs (miRNAs) encoded by viral genome or host have been found participating in host-microbe interactions. Differential expression profiles of miRNAs were shown linking to specific disease pathologies which indicated its potency as diagnostic/prognostic biomarkers of infectious disease. This was emphasized by the discovery of circulating miRNAs which were found to be remarkably stable in mammalian biofluids. Standardized methods of miRNA quantification including RNA isolation should be established before they will be ready for use in clinical practice.

Effects of mRNA secondary structure on the expression of HEV ORF2 proteins in Escherichia coli

Background

Viral protein expression in Escherichia coli (E. coli) is a powerful tool for structural/functional studies as well as for vaccine and diagnostics development. However, numerous factors such as codon bias, mRNA secondary structure and nucleotides distribution, have been indentified to hamper this heterologous expression.

Results

In this study, we combined computational and biochemical methods to analyze the influence of these factors on the expression of different segments of hepatitis E virus (HEV) ORF 2 protein and hepatitis B virus surface antigen (HBsAg). Three out of five HEV antigens were expressed while all three HBsAg fragments were not. The computational analysis revealed a significant difference in nucleotide distribution between expressed and non-expressed genes; and all these non-expressing constructs shared similar stable 5′-end mRNA secondary structures that affected the accessibility of both Shine-Dalgarno (SD) sequence and start codon AUG. By modifying the 5′-end of HEV and HBV non-expressed genes, there was a significant increase in the total free energy of the mRNA secondary structures that permitted the exposure of the SD sequence and the start codon, which in turn, led to the successful expression of these genes in E. coli.

Conclusions

This study demonstrates that the mRNA secondary structure near the start codon is the key limiting factor for an efficient expression of HEV ORF2 proteins in E. coli. It describes also a simple and effective strategy for the production of viral proteins of different lengths for immunogenicity/antigenicity comparative studies during vaccine and diagnostics development.

Electronic supplementary material

The online version of this article (10.1186/s12934-017-0812-8) contains supplementary material, which is available to authorized users.

Curcumin inhibits hepatitis B virus infection by down-regulating cccDNA-bound histone acetylation

AIM

To investigate the potential effect of curcumin on hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) and the underlying mechanism.

METHODS

A HepG2.2.15 cell line stably transfected with HBV was treated with curcumin, and HBV surface antigen (HBsAg) and e antigen (HBeAg) expression levels were assessed by ELISA. Intracellular HBV DNA replication intermediates and cccDNA were detected by Southern blot and real-time PCR, respectively. The acetylation levels of histones H3 and H4 were measured by Western blot. H3/H4-bound cccDNA was detected by chromatin immunoprecipitation (ChIP) assays. The deacetylase inhibitors trichostatin A and sodium butyrate were used to study the mechanism of action for curcumin. Additionally, short interfering RNAs (siRNAs) targeting HBV were tested along with curcumin.

RESULTS

Curcumin treatment led to time- and dose-dependent reductions in HBsAg and HBeAg expression and significant reductions in intracellular HBV DNA replication intermediates and HBV cccDNA. After treatment with 20 μmol/L curcumin for 2 d, HBsAg and cccDNA levels in HepG2.2.15 cells were reduced by up to 57.7% (P < 0.01) and 75.5% (P < 0.01), respectively, compared with levels in non-treated cells. Meanwhile, time- and dose-dependent reductions in the histone H3 acetylation levels were also detected upon treatment with curcumin, accompanied by reductions in H3- and H4-bound cccDNA. Furthermore, the deacetylase inhibitors trichostatin A and sodium butyrate could block the effects of curcumin. Additionally, transfection of siRNAs targeting HBV enhanced the inhibitory effects of curcumin.

CONCLUSION

Curcumin inhibits HBV gene replication via down-regulation of cccDNA-bound histone acetylation and has the potential to be developed as a cccDNA-targeting antiviral agent for hepatitis B.

聚乙二醇干扰素α-2a联合胸腺肽α1治疗慢性乙型肝炎疗效的系统评价

目的

系统评价聚乙二醇干扰素α-2a(pegylated interferon α-2a, Peg-IFNα-2a)联合胸腺肽α1(thymosin α 1, Tα1)与单用Peg-IFNα-2a治疗慢性乙型肝炎(chronic hepatitis B, CHB)的疗效及安全性.

方法

检索PubMed、EMBASE、The Cochrane Library、CBM、CNKI、VIP和WanFang Data, 查找Peg-IFNα-2a联合Tα1治疗CHB的随机对照试验(randomized controlled trial, RCT), 检索年限从建库至2016-10, 由2位评价员根据纳入与排除标准独立筛选文献, 从纳入的文献中提取资料并进行质量评价, 采用RevMan5.3软件进行Meta分析.

结果

最终纳入7个RCT, 包括640例患者. Meta分析结果显示: 与单用Peg-IFNα-2a治疗CHB相比, 联合Tα1治疗结束时明显提高了血清ALT复常率(OR = 2.94, 95%CI: 1.59-5.44, P = 0.0006)、HBV-DNA阴转率(OR = 2.53, 95%CI: 1.76-3.64, P<0.00001)、乙型肝炎e抗原(hepatitis B e antigen, HBeAg)阴转率(OR = 2.21, 95%CI: 1.43-3.40, P = 0.0003)、HBeAg血清转换率(OR = 2.53, 95%CI: 1.48-4.30, P = 0.0006)、乙型肝炎表面抗原阴转率(OR = 2.67, 95%CI: 1.07-6.69, P = 0.04). 联合治疗后不增加Peg-IFNα-2a的不良反应(流感样症状)发生率, 差异无统计学意义(OR = 0.8, 95%CI: 0.24-2.63, P = 0.71).

结论

Peg-IFNα-2a联合Tα1治疗CHB结束时的疗效优于单用Peg-IFNα-2a, 其安全性良好, 但受纳入研究数量和质量的限制, 停药后的长期效果如何尚缺乏证据, 需开展更多高质量的RCT进一步研究.

Chronic Hepatitis B, C, and D

Chronic hepatitis B, C, and D virus infections contribute significantly to the morbidity and mortality of immunocompromised individuals. To contextualize discussion of these infections in immunocompromised patients, this paper provides an overview of aspects of infection in normal hosts. It then describes differences in disease, diagnostic testing, and therapeutic management observed in immunocompromised patients.

Retrospective analysis of hepatitis B virus chronic infection in 247 patients: clinical stages, response to treatment and poor prognostic factors

Background

Chronic hepatitis B is a major cause of cirrhosis, and the natural history of the disease has several clinical stages that should be thoroughly understood for the implementation of proper treatment. Nonetheless, curing the disease with antiviral treatment remains a challenge.

Aims

To describe the clinical course, response to treatment, and poor prognostic factors in 247 hepatitis B virus chronic infection patients treated in a tertiary hospital in Brazil.

Methods

This was a retrospective and observational study, by analyzing the medical records of HBV infected patients between January 2000 and January 2015.

Results

Most patients were male (67.2%) and 74.1% were HBeAg negative. Approximately 41% had cirrhosis and 8.5% were hepatitis C virus coinfected. The viral load was negative after two years on lamivudine, entecavir and tenofovir in 86%, 90.6%, and 92.9% of the patients, respectively. The five-year resistance rates for lamivudine, adefovir, entecavir, and tenofovir were 57.5%, 51.8%, 1.9%, and 0%, respectively. The overall seroconversion rates were 31.2% for HBeAg and 9.4% for HBsAg. Hepatocellular carcinoma was diagnosed in 9.7% of patients, liver transplantation was performed in 9.7%, and overall mortality was 10.5%. Elevations of serum alanine aminotransferase (p = 0.0059) and viral load (p < 0.0001) were associated with progression to liver cirrhosis. High viral load was associated with progression to hepatocellular carcinoma (p < 0.0001). Significant risk factors associated with death were elevated alanine aminotransferase (p = 0.0039), liver cirrhosis (p < 0.0001), high viral load (p = 0.007), and hepatocellular carcinoma (p = 0.0008). HBeAg positive status was not associated with worse outcomes, and treatment may have been largely responsible.

Conclusions

Elevations of viral load and serum alanine aminotransferase may select patients with worse prognosis, especially progression to cirrhosis and hepatocellular carcinoma, which were strongly association with death.

Spontaneous clearance of chronic hepatitis C is rare in HIV-infected patients after effective use of combination antiretroviral therapy

Objective

To evaluate the rate of spontaneous resolution of chronic hepatitis C (CHC) infection in a cohort of HIV-infected patients.

Methods

A retrospective analysis of 509 HIV-infected patients with chronic HCV infection was performed at two reference hospitals in Andalusia. The main variable of the study was spontaneous clearance of CHC, defined as a negative HCV RNA result after at least two previous quantitative measurements of HCV RNA separated by a minimum of 12 months.

Results

Of 509 patients, 3 (0.59%; 95% CI: 0.15%-1.6%) experienced spontaneous clearance of CHC. After combination antiretroviral therapy (cART) initiation, two of three cases experienced an increased CD4⁺ count, coinciding with HCV viral clearance. All patients were IL28B CC carriers, 2 were co-infected with HCV genotype 3 (the HCV genotype of the remaining patient was not available).

Conclusions

Spontaneous clearance of CHC is a rare event in the context of HIV/HCV co-infected patients and may be associated with the effective use of cART and thus HIV suppression.

Past, Current, and Future Developments of Therapeutic Agents for Treatment of Chronic Hepatitis B Virus Infection

For decades, treatment of hepatitis B virus (HBV) infection has been relying on interferon (IFN)-based therapies and nucleoside/nucleotide analogues (NAs) that selectively target the viral polymerase reverse transcriptase (RT) domain and thereby disrupt HBV viral DNA synthesis. We have summarized here the key steps in the HBV viral life cycle, which could potentially be targeted by novel anti-HBV therapeutics. A wide range of next-generation direct antiviral agents (DAAs) with distinct mechanisms of actions are discussed, including entry inhibitors, transcription inhibitors, nucleoside/nucleotide analogues, inhibitors of viral ribonuclease H (RNase H), modulators of viral capsid assembly, inhibitors of HBV surface antigen (HBsAg) secretion, RNA interference (RNAi) gene silencers, antisense oligonucleotides (ASOs), and natural products. Compounds that exert their antiviral activities mainly through host factors and immunomodulation, such as host targeting agents (HTAs), programmed cell death protein 1 (PD-1)/programmed death ligand 1 (PD-L1) inhibitors, and Toll-like receptor (TLR) agonists, are also discussed. In this Perspective, we hope to provide an overview, albeit by no means being comprehensive, for the recent development of novel therapeutic agents for the treatment of chronic HBV infection, which not only are able to sustainably suppress viral DNA but also aim to achieve functional cure warranted by HBsAg loss and ultimately lead to virus eradication and cure of hepatitis B.

Different Mechanisms May Exist for HBsAg Synthesis and Secretion During Various Phases of Chronic Hepatitis B Virus Infection

BACKGROUND The aim of this study was to characterize the expression and secretion of hepatitis B surface-antigen (HBsAg) in the hepatocytes of hepatitis B virus (HBV)-infected patients at different phases of infection; as such, the association of intrahepatic HBsAg expression with virological markers and the histological characteristics were analyzed. MATERIAL AND METHODS 302 chronic HBV infection patients who had not received antiviral therapy were stratified by HBeAg status. The proportion of HBsAg-positive cells was used as an indicator for HBsAg expression level. RESULTS In HBeAg-positive patients, there was a significant correlation between serum HBsAg and serum HBV DNA levels (r=0.569, p<0.001). Intrahepatic HBsAg expression and serum HBsAg level in HBeAg-positive patients were higher than those in HBeAg-negative patients (p=0.002 and p<0.001, respectively). A significant correlation between serum HBsAg level and intrahepatic HBsAg expression was found in HBeAg-negative patients (r=0.377, p<0.001), but not in HBeAg-positive patients (r=0.051, p=0.557). Very interestingly, the correlation between serum HBsAg level and HBsAg expression in hepatocytes gradually increased along with disease progression through the immune-tolerant, immune-clearance, inactive, and recovery phases of HBV infection (r=-0.184, 0.068, 0.492, and 0.575; and p=0,238, 0,722, 0.012, and 0.002, respectively). CONCLUSIONS Different mechanisms may be involved in HBsAg synthesis and secretion in different phases of chronic HBV infection.

Potential strategies for "cure" of hepatitis B

Hepatitis B is a worldwide health problem and the main cause of liver cirrhosis, liver failure, and liver cancer. The steady state of hepatitis B virus (HBV) covalently closed circular DNA (cccDNA) in HBV infected hepatocytes and virus specific immune tolerance contribute to the chronic persistent infection and hard-to-cure of hepatitis B. The presently available therapeutics for hepatitis B can control viral replication, but rarely eliminate HBV surface antigen (HBsAg) or HBV cccDNA. The "cure" of hepatitis B, which is characterized by the HBsAg loss or HBsAg seroconversion, and cccDNA clearance, has been the goal of researchers for years. In recent years, with the robust progress in understanding the HBV pathogenesis and the rapid development of gene editing technology, the "cure" of hepatitis B becomes prospective. This paper aims to summarize the potential strategies for the "cure" of hepatitis B.

Efficacy of switching from adefovir to tenofovir in chronic hepatitis B patients who exhibit suboptimal responses to adefovir-based combination rescue therapy due to resistance to nucleoside analogues (SATIS study)

Background/Aims

It remains to be determined whether switching from adefovir (ADV) to tenofovir (TDF) provides better virological outcomes in patients exhibiting suboptimal responses to ADV plus nucleoside analogue (ADV+NA) therapy for NA-resistant chronic hepatitis B (CHB).

Methods

In this prospective trial, patients who showed partial responses (defined as serum hepatitis B virus [HBV] DNA >60 IU/mL) to ADV+NA therapy for NA resistance were randomly allocated to receive TDF plus NA (TDF+NA group, n=16) or to continue their current therapy (ADV+NA group, n=16). The primary end point was the proportion of patients with complete virological response (CVR, defined as serum HBV DNA <60 IU/mL) at 48 weeks.

Results

The median age was 52 years (16 men), and 28 were positive for hepatitis B e antigen (HBeAg). The baseline characteristics did not differ significantly between the two groups. The proportion with CVR was significantly higher in the TDF+NA group than in the ADV+NA group at 24 weeks (81.3% vs. 25.0%, P=0.001) and 48 weeks (87.5% vs. 37.5%, P=0.002). Furthermore, a decrease in the serum HBV DNA level of >2log₁₀ IU/mL was more likely in the TDF+NA group at both 24 and 48 weeks (68.8% vs. 56.3%, P=0.014 vs. 81.3% vs. 56.3%, P=0.001, respectively). During the follow-up, the rate of HBeAg seroconversion was higher in the TDF+NA group than the ADV+NA group (12.5% vs. 6.25%, P=0.640), as was that for the hepatitis B surface antigen (6.25% vs. 0%, P=0.080). No serious adverse events due to antiviral agents occurred.

Conclusion

In patients exhibiting suboptimal responses to ADV+NA therapy for NA-resistant CHB, switching from ADV to TDF might provide better virological outcomes.

Antiviral therapy of persistent viral infection using genome editing

Chronic viral infections are often incurable because current antiviral strategies do not target chromosomally integrated or non-replicating episomal viral genomes. The rapid development of technologies for genome editing may possibly soon allow for therapeutic targeting of viral genomes and, hence, for development of curative strategies for persistent viral infection. However, detailed investigation of different antiviral genome editing approaches recently revealed various undesired effects. In particular, the problem of frequent and swift development of resistant viruses has to be thoroughly analysed before genome editing approaches become an established option for antiviral treatment.

Design and Synthesis of Orally Bioavailable 4-Methyl Heteroaryldihydropyrimidine Based Hepatitis B Virus (HBV) Capsid Inhibitors

Targeting the capsid protein of hepatitis B virus (HBV) and thus interrupting normal capsid formation have been an attractive approach to block the replication of HBV viruses. We carried out multidimensional structural optimizations based on the heteroaryldihydropyrimidine (HAP) analogue Bay41-4109 (1) and identified a novel series of HBV capsid inhibitors that demonstrated promising cellular selectivity indexes, metabolic stabilities, and in vitro safety profiles. Herein we disclose the design, synthesis, structure-activity relationship (SAR), cocrystal structure in complex with HBV capsid proteins and in vivo pharmacological study of the 4-methyl HAP analogues. In particular, the (2S,4S)-4,4-difluoroproline substituted analogue 34a demonstrated high oral bioavailability and liver exposure and achieved over 2 log viral load reduction in a hydrodynamic injected (HDI) HBV mouse model.

Specific CD8+ T cell response immunotherapy for hepatocellular carcinoma and viral hepatitis

Hepatocellular carcinoma (HCC), chronic hepatitis B (CHB) and chronic hepatitis C (CHC) are characterized by exhaustion of the specific CD8⁺ T cell response. This process involves enhancement of negative co-stimulatory molecules, such as programmed cell death protein-1 (PD-1), cytotoxic T-lymphocyte antigen-4 (CTLA-4), 2B4, Tim-3, CD160 and LAG-3, which is linked to intrahepatic overexpression of some of the cognate ligands, such as PD-L1, on antigen presenting cells and thereby favouring a tolerogenic environment. Therapies that disrupt these negative signalling mechanisms represent promising therapeutic tools with the potential to restore reactivity of the specific CD8⁺ T cell response. In this review we discuss the impressive in vitro and in vivo results that have been recently achieved in HCC, CHB and CHC by blocking these negative receptors with monoclonal antibodies against these immune checkpoint modulators. The article mainly focuses on the role of CTLA-4 and PD-1 blocking monoclonal antibodies, the first ones to have reached clinical practice. The humanized monoclonal antibodies against CTLA-4 (tremelimumab and ipilimumab) and PD-1 (nivolumab and pembrolizumab) have yielded good results in testing of HCC and chronic viral hepatitis patients. Trelimumab, in particular, has shown a significant increase in the time to progression in HCC, while nivolumab has shown a remarkable effect on hepatitis C viral load reduction. The research on the role of ipilimumab, nivolumab and pembrolizumab on HCC is currently underway.

Hepatitis B Virus Infection in the General Population of Iran: An Updated Systematic Review and Meta-Analysis

CONTEXT

The hepatitis B virus (HBV) is a major global public health problem, affecting more than 2 billion people worldwide. Accurate and updated data on HBV prevalence is important for further planning to control the infection. The aim of this study was to update the prevalence estimate of HBV infection in the general population of Iran.

EVIDENCE ACQUISITION

A systematic review was done for data on the prevalence of HBV infection in the general Iranian population published between Jan. 1, 1990, and Jan. 1, 2016, in both international and national databases, including PubMed, Scopus, Web of Science, Scientific Information Database, IranMedex, and Magiran. All papers with clearly described time and location of the study, proper sampling strategies, and proper analysis methods were included in the present study. Data were extracted by two independent reviewers. Prevalence of HBV infection with a 95% confidence interval (CI) was calculated using Stata software, version 13.

RESULTS

The polled estimated prevalence of HBV infection in the general population of Iran was 2.2 % (95% CI: 1.9% - 2.6%). The highest prevalence of HBV infection (8.9%, 95% CI: 7.6% - 10.2%) was reported from Golestan province, and the lowest prevalence (0.7%, 95% CI: 0.4% - 1.1%) was seen in Kermanshah province. The prevalence of HBV infection was estimated at 3% (95% CI: 2.2% - 3.8%) for Iranian males and 1.7% (95% CI: 1.2% - 2.3%) for Iranian females. The prevalence of HBV infection in the general population of Iran was 2.9% (95% CI: 2.5% - 3.4%) before 2010 and 1.3% (95% CI: 0.9% - 1.7%) after 2010.

CONCLUSIONS

In total, Iran was classified within the low-intermediate HBV prevalence areas (2% - 4%), while according to recent data (after 2010), Iran was classified within the low HBV prevalence areas (< 2%), indicating that preventive measures conducted in Iran have been effective.