Hepatitis B inactive carriers: An overlooked population?

The Role of Glutathione in Selected Viral Diseases

During inflammatory processes, immunocompetent cells are exposed to substantial amounts of free radicals and toxic compounds. Glutathione is a cysteine-containing tripeptide that is an important and ubiquitous antioxidant molecule produced in human organs. The intracellular content of GSH regulates the detoxifying capacity of cells, as well as the inflammatory and immune response. GSH is particularly important in the liver, where it serves as the major non-protein thiol involved in cellular antioxidant defense. There are numerous causes of hepatitis. The inflammation of the liver can be caused by a variety of infectious viruses. The relationship between oxidative stress and the hepatitis A virus (HAV), hepatitis B virus (HBV), hepatitis C virus (HCV), and hepatitis E virus (HEV) infection is not fully known. The aim of this study was to examine the relationship between hepatotropic viruses and glutathione status, including reduced glutathione (GSH) and oxidized glutathione (GSSG), as well as antioxidant enzymes, e.g., glutathione peroxidase (GPx), glutathione reductase (GR) and glutathione-S-transferase (GST) in liver diseases.

Hepatitis B Virus-Encoded HBsAg Contributes to Hepatocarcinogenesis by Inducing the Oncogenic Long Noncoding RNA LINC00665 through the NF-κB Pathway

Clinical and in vivo studies have demonstrated a role for hepatitis B virus (HBV)-encoded HBsAg (hepatitis B surface antigen) in HBV-related hepatocellular carcinoma (HCC); however, the underlying mechanisms remain largely unknown. Here, we investigated the role of HBsAg in regulating long noncoding RNAs (lncRNAs) involved in HCC progression. Our analysis of microarray data sets identified LINC00665 as an HBsAg-regulated lncRNA. Furthermore, LINC00665 is upregulated in liver samples from HBV-infected patients as well as in HCC, specifically in HBV-related HCC liver samples. These findings were supported by our in vitro data demonstrating that HBsAg, as well as HBV, positively regulates LINC00665 in multiple HBV cell culture models. Next, we evaluated the oncogenic potential of LINC00665 by its overexpression and CRISPR interference (CRISPRi)-based knockdown in various cell-based assays. LINC00665 promoted cell proliferation, migration, and colony formation but inhibited cell apoptosis in vitro. We then identified the underlying mechanism of HBsAg-mediated regulation of LINC00665. We used immunofluorescence assays to show that HBsAg enhanced the nuclear translocation of NF-κB factors in HepG2 cells, confirming that HBsAg activates NF-κB. Inhibition of NF-κB signaling nullified HBsAg-mediated LINC00665 upregulation, suggesting that HBsAg acts through NF-κB to regulate LINC00665. Furthermore, the LINC00665 promoter contains NF-κB binding sites, and their disruption abrogated HBsAg-induced LINC00665 upregulation. Finally, HBsAg facilitated the enrichment of the NF-κB factors NF-κB1, RelA, and c-Rel in the LINC00665 promoter. Taken together, this work shows that HBsAg can drive hepatocarcinogenesis by upregulating oncogenic LINC000665 through the NF-κB pathway, thereby identifying a novel mechanism in HBV-related HCC. IMPORTANCE Hepatitis B virus (HBV) is a major risk factor for hepatocellular carcinoma (HCC). Numerous reports indicate an oncogenic role for HBV-encoded HBsAg; however, the underlying mechanisms are not well understood. Here, we studied the role of HBsAg in regulating lncRNAs involved in hepatocarcinogenesis. We demonstrate that HBsAg, as well as HBV, positively regulates oncogenic lncRNA LINC00665. The clinical significance of this lncRNA is highlighted by our observation that LINC00665 is upregulated in liver samples during HBV infection and HBV-related HCC. Furthermore, we show LINC00665 can drive hepatocarcinogenesis by promoting cell proliferation, colony formation, and cell migration and inhibiting apoptosis. Taken together, this work identified LINC00665 as a novel gene through which HBsAg can drive hepatocarcinogenesis. Finally, we show that HBsAg enhances LINC00665 levels in hepatocytes by activating the NF-κB pathway, thereby identifying a novel mechanism by which HBV may contribute to HCC.

Association between the HLA-DQB1 Gene Polymorphism and Chronic Progression of Hepatitis B in Indonesia

BACKGROUND: The progression of hepatitis B is affected by the activity of T lymphocytes. Activation of T lymphocytes requires a primary signal originating from the presentation of antigen by HLA molecules to T cell receptors. HLA-DQB1 gene polymorphisms can affect the ability of HLA to bind and present viral antigens to T cells, thus affecting T cell activation and potentially associated with the progression of chronic hepatitis B. AIM: We aimed to investigate the polymorphisms of the HLA-DQB1 gene and its influence on chronic hepatitis B progression of chronic hepatitis B patients in Indonesia. METHODS: This cross-sectional research studied chronic hepatitis B patients at the Internal Medicine Department, Arifin Ahmad Hospital, Pekanbaru, from January 2018 to December 2018. Subjects were grouped into three categories: (1) Inactive chronic hepatitis B, (2) active chronic hepatitis B, and (3) end stage liver disease (ESLD) which consisted of patients with liver cirrhosis and hepatocellular carcinoma. Examination of the HLA-DQB1 gene polymorphism was performed with the SSP-PCR method and sequenced to verify the PCR results. Analysis results of p < 0.05 were considered statistically significant. RESULTS: The most common allele in patients with chronic hepatitis B was the HLA-DQB1 0301. The HLA-DQB1 0301 allele found primarily in the inactive chronic hepatitis B group. The DQB1 0501 allele found to be more abundant in patients with active chronic hepatitis B. The HLA DQB1 0502 allele only found in patients with chronic hepatitis B with ESLD. CONCLUSIONS: The HLA-DQB1 gene polymorphism is associated with the progression of chronic hepatitis B in chronic hepatitis B patients in Indonesia.

The role of quantitative HBsAg in the natural history of e antigen-negative chronic hepatitis B: A Tunisian prospective study

BACKGROUND/AIMS

During the natural course of Chronic Hepatitis B (CHB) infection, differentiation between inactive carrier (IC) and HBeAg negative CHB is a subject of ongoing debate. We studied the role of hepatitis B surface antigen (HBsAg) level as a means of differentiating between CHB and IC in a group of untreated chronic HBeAg-negative HBV-infected patients.

STUDY

A total of 115 HBeAg negative carriers were enrolled and followed up for>12 months; 78 as inactive carriers (IC), and 37 as active carriers (AC). Among ACs, patients were categorized according to the highest rate of viral load: AC1 (n=23), active carriers with persistent HBV-DNA<20,000 IU/mL; AC2 (n=14), active carriers with HBV-DNA>20,000 IU/mL.

RESULTS

HBsAg levels were higher in AC compared to IC patients (1607 IU/ml vs. 225 IU/ml respectively, P=0.001). Among the AC group, the 23 AC1 cases had HBsAg levels significantly lower than the 14 AC2 patients (1756 IU/mL vs. 3327 IU/mL respectively; P<10^-3). HBsAg showed weak correlation with HBV-DNA in the whole cohort (r=0.44, P<0.01). The suggested cutoff value of HBsAg titer to differentiate between the two groups was 938 IU/mL. Combined single-point quantification of HBsAg (938 IU/mL) and HBV DNA (2000 IU/mL) identified IC with 87.2% specificity and 91.7% positive predictive value.

CONCLUSION

This study confirms the predictability of a one-time combined HBsAg and HBV DNA measurement for true inactive carriers requiring neither strict follow-up nor antiviral treatment.

Global dynamics of a model of hepatitis B virus infection in a sub-Saharan African rural area

We formulate and systematically study a deterministic compartmental model of Hepatitis B. This model has some important and novel features compared with the well-known basic model in the literature. Specifically, it takes into account the differential susceptibility that follows the vaccine formulation employing three-doses schedule. It points up the HbeAg status of carriers, their levels of viral replication, the fact that treatment being not curative is recommended only to a small proportion of chronic carriers, and finally the fact that only inactive carriers are able to recover from disease. The model has simple dynamical behavior which has a globally asymptotically stable disease-free equilibrium when the basic reproduction number [Formula: see text] and an endemic equilibrium when [Formula: see text]. By the use of Lyapunov functions, when it exists, we prove the global asymptotic stability of the endemic equilibrium under some conditions. Using data from Tokombere, a rural area in Cameroon, numerical simulations are performed. These numerical simulations first confirm analytical results, second they suggest that a policy based on treatment could not significantly impact the course of the infection. Third, they show as it is well known that vaccination is a very effective measure to control the infection. Furthermore, they show that neonatal vaccination influences more the course of infection than mass vaccination strategy. Nevertheless, they picture how much loss between consecutive doses of vaccine could be harmful. Finally, it is suggested that for a Sub-saharan African rural area, two-thirds of expected incidence of Hepatitis B virus infection and one third of expected prevalence of chronic carriers could be averted by 2030 if the birth dose vaccination becomes systematic and if mass vaccination rate increases to up 10%.

MicroRNAs and exosomes: key players in HIV pathogenesis

OBJECTIVES

HIV infection is well known to cause impairment of the human immune system, and until recently was a leading cause of death. It has been shown that T lymphocytes are the main targets of HIV. The virus inactivates T lymphocytes by interfering with a wide range of cellular and molecular targets, leading to suppression of the immune system. The objective of this review is to investigate to what extent microRNAs (miRNAs) are involved in HIV pathogenesis.

METHODS

The scientific literature (Pubmed and Google scholar) for the period 1988-2019 was searched.

RESULTS

Mounting evidence has revealed that miRNAs are involved in viral replication and immune response, whether by direct targeting of viral transcripts or through indirect modulation of virus-related host pathways. In addition, exosomes have been found to act as nanoscale carriers involved in HIV pathogenesis. These nanovehicles target their cargos (i.e. DNA, RNA, viral proteins and miRNAs) leading to alteration of the behaviour of recipient cells.

CONCLUSIONS

miRNAs and exosomes are important players in HIV pathogenesis. Additionally, there are potential diagnostic applications of miRNAs as biomarkers in HIV infection.

Characterization and assessment of HBV chronically infected patients: Identification of those eligible for treatment in the South West region of Cameroon

BACKGROUND

The management of patients with chronic hepatitis B infection is quite complex because it requires an in-depth knowledge of the natural history of the disease. This study was aimed at characterizing HBV infected patients in order to determine the phase of the infection and identify the proportion eligible for treatment using 3 different guidelines.

METHODS

HBV chronically infected patients (negative for HIV and HCV) were enrolled and the following tests were done for them: ALT, AST, HBV viral load, HBV serologic panel and Full blood count. APRI score was calculated for all patients. These patients were classified into immunotolerant, immune clearance, immune control and immune escape phases of the infection. The WHO and the 2018 AASLD criteria was also used to identify those who need treatment. Patients were clinically examined for signs and symptoms. Questionnaire was administered to all participants to ascertain their treatment status. Statistical analysis was done using SPSS version 21.

RESULTS

A total of 283 participants (101 females and 182 males) with a mean age of 31.3±8.5 were enrolled. Fifty-two (18.4%) were eligible for treatment (Immune clearance and immune escape phases) and they recorded a significantly higher mean APRI score (0.71±0.51) as compared to those in the immune control and immune tolerant phase (0.43±0.20). Based on WHO and AASLD criteria, 12(4.2%) and 15 (5.3%) were eligible for treatment respectively and these were all subsets of the 52 cases mentioned above. Six (2.1%) and 29 (10.2%) of those identified under the immune control phase were on tenofovir and traditional medication respectively.

CONCLUSION

Considering treatment for patients in the immune clearance and immune escape phases of the infection can be a reliable strategy to implement in our setting as this may probably tie with considerations from other treatment guidelines. Fifty-two (18.4%) patients were eligible for treatment and none of them were among the 2.1% of patients put on Tenofovir based treatment. This calls for the need for more trained health experts to periodically assess patients, implement an adequate treatment guideline and place the right patients on treatment in Cameroon.

Interference of Apoptosis by Hepatitis B Virus

Hepatitis B virus (HBV) causes liver diseases that have been a consistent problem for human health, leading to more than one million deaths every year worldwide. A large proportion of hepatocellular carcinoma (HCC) cases across the world are closely associated with chronic HBV infection. Apoptosis is a programmed cell death and is frequently altered in cancer development. HBV infection interferes with the apoptosis signaling to promote HCC progression and viral proliferation. The HBV-mediated alteration of apoptosis is achieved via interference with cellular signaling pathways and regulation of epigenetics. HBV X protein (HBX) plays a major role in the interference of apoptosis. There are conflicting reports on the HBV interference of apoptosis with the majority showing inhibition of and the rest reporting induction of apoptosis. In this review, we described recent studies on the mechanisms of the HBV interference with the apoptosis signaling during the virus infection and provided perspective.

Hepatitis B Virus Inactive Carriers: Which Follow-up Strategy?

Introduction

The natural history of patients with inactive hepatitis B virus (HBV) is still unclear, persisting doubts about the optimal management of these patients.

Aim

To evaluate the long-term outcome in a cohort of hepatitis B inactive carriers.

Methods

We conducted a retrospective study in a cohort of 100 HBV inactive carriers (categorized after quarterly determinations of serum ALT and HBV DNA over one year) and analyzed the results of serial determinations of HBV DNA and alanine transaminase (ALT). The HBV DNA was quantified by Cobas TaqMan^®. We used the Spearman's rank correlation coefficient to evaluate the correlation between the serum ALT and HBV DNA.

Results

We studied 100 HBV inactive carriers (53% females, mean age 48.7 ± 13.8 years, range 16–77 year). Vertical transmission was identified in 18%. The mean follow-up time was 4.6 ± 2.5 (2–13) years. Two patients had transient elevation of ALT (alcohol and drugs). We observed clearance of hepatitis B surface antigen (HBsAg) in four patients (4%) and biological and virological reactivation in 10% (from the 4th year of follow-up). Mild lesions were found in the 12 patients in whom liver biopsy was performed; genotypes A and D predominated. Viral load and serum ALT levels were unremarkable in 90% of the patients. There was no significant correlation (p > 0.05) between the values of ALT and HBV DNA throughout the follow-up.

Conclusion

The management strategy, using both patterns of biochemical and virologic activity, seems adequate. The lack of correlation between the values of ALT and HBV DNA caveat its effectiveness and the stability of the levels of HBV DNA and ALT in most patients suggests that the prognosis of the inactive carriers, when defined accurately, is mostly benign. Further studies, including ones with new tests available, are needed to standardize and improve the management of this group of patients.