Natural history of chronic hepatitis B virus infection from infancy to adult life - the mechanism of inflammation triggering and long-term impacts

Hurdles to the Development of Effective HBV Immunotherapies and HCV Vaccines

Chronic infections with HBV and HCV continue to be major public health problems, with hundreds of millions of people infected worldwide; this is despite the availability of both an effective prophylactic HBV vaccine for more than 3 decades and potent direct antivirals for HBV and, more recently, HCV infection. Consequently, development of HBV immunotherapies and prophylactic HCV vaccines remains extremely urgent, but limited funding and significant gaps in our understanding of the correlates of immune protection pose serious hurdles for the development of novel immune-based interventions. Here we discuss immunological questions related to HBV and HCV, some shared and some pertinent to only 1 of the viruses, that should be addressed for the rational design of HBV immunotherapies and HCV vaccines.

Role of interleukin-23 in monocyte-derived dendritic cells of HBV-related acute-on-chronic liver failure and its correlation with the severity of liver damage

BACKGROUND

The role of interleukin-23 (IL-23) in monocyte-derived dendritic cells (MoDCs) from hepatitis B virus-related acute-on-chronic liver failure (HBV-ACLF) patients remains unclear. The aim of this study was to observe the correlation between the activation of the IL-23 signaling pathway and the prognosis of HBV-ACLF patients.

MATERIALS AND METHODS

The baseline levels of serum IL-6, IL-12, IL-17, IL-23, tumor necrosis factor-α (TNF-α), and interferon-γ (IFN-γ) from immune tolerant (IT), chronic hepatitis B (CHB), HBV-ACLF patients and healthy individuals who served as healthy controls (HCs) were analyzed using the Luminex system, whereas serum IL-23 from HBV-ACLF patients was measured by ELISA before and after treatment. Purified monocytes were isolated from peripheral blood and were induced into MoDCs, IL-23, IL-23R, NF-κB and TRAF6 expression in MoDCs from 4 groups was analyzed using real-time PCR, and IL-23R and intracellular IL-23 were evaluated by flow cytometry.

RESULTS

Serum IL-6, IL-12, IL-17, IL-23 and TNF-α levels were upregulated in HBV-ACLF patients compared with IT patients, CHB patients and HCs (P<0.05 for all). Serum IL-23 was closely correlated with elevated serum IL-17 in HBV-ACLF patients (r=0.5935, P<0.0001). Moreover, IL-23 and IL-23R levels were significantly upregulated in MoDCs from patients with CHB or HBV-ACLF compared with HCs, and further upregulation of IL-23 and IL-23R was observed in HBV-ACLF patients compared to CHB patients (P<0.05 for all). IL-23 expression was markedly enhanced and was correlated with elevated NF-κB and TRAF6 in MoDCs from HBV-ACLF patients (P<0.05 for both). Linear correlation analysis demonstrated significant correlations between the expression of IL-23 and disease severity markers (MELD scoring system, international normalized ratio, prothrombin time and total bilirubin, r=0.6874, r=0.6475, r=0.6249, r=0.3771, respectively, P<0.05 for all) for individual HBV-ACLF patients, and IL-23 levels were significantly upregulated in non-survival HBV-ACLF patients compared with survival HBV-ACLF patients (P<0.05).

CONCLUSION

IL-23 in serum and MoDCs is significantly elevated in HBV-ACLF patients, TRAF6/NF-κB may play a role in IL-23 production by MoDCs in HBV-ACLF patients and high pre-treatment IL-23 levels in MoDCs are associated with mortality in HBV-ACLF patients.

Evaluation of APRI and FIB-4 for noninvasive assessment of significant fibrosis and cirrhosis in HBeAg-negative CHB patients with ALT ≤ 2 ULN: A retrospective cohort study

To evaluate the performance of aspartate transaminase-to-platelet ratio index (APRI) and fibrosis index based on four factors (FIB-4) to predict significant fibrosis and cirrhosis in hepatitis B virus e antigen (HBeAg)-negative chronic hepatitis B (CHB) patients with alanine transaminase (ALT) ≤ twice the upper limit of normal (2 ULN).Histologic and laboratory data of 236 HBeAg-negative CHB patients with ALT ≤ 2 ULN were analyzed. Predicted fibrosis stage, based on established scales and cut-offs for APRI and FIB-4, was compared with METAVIR scores obtained from liver biopsy.In this study, the areas under the receiver operating characteristic curves (AUROCs) of APRI were lower than that of FIB-4 (0.62 vs 0.69; P = 0.019) for diagnosing significant fibrosis; however APRI and FIB-4 were comparable for diagnosing cirrhosis (0.77 vs 0.81; P = 0.374). When the cut-off proposed by WHO HBV guideline for APRI (>2.0) was used, no cirrhotic patients were correctly predicted. For FIB-4, the WHO proposed cut-off of 3.25 correctly identified significant fibrosis 83% of the time; but for APRI, the WHO proposed cut-off of 1.5 identified significant fibrosis 56%. In ruling out significant fibrosis, the WHO proposed APRI cut-off of 0.5 had a predictive value of 39%, and the FIB-4 cut-off of 1.45 correctly identified lack of significant fibrosis in 47% of the patients. In this study, based on ROC analysis, the optimal cut-offs were 0.46 and 0.65 for APRI, and 1.05 and 1.29 for FIB-4, for diagnosing significant fibrosis and cirrhosis, respectively. When the new cut-off of APRI (>0.65) was used, 82% of the cirrhotic patients were correctly predicted. In ruling out significant fibrosis, the new APRI cut-off (<0.46) had a predictive value of 80%, and new FIB-4 cut-off (<1.05) correctly identified lack of significant fibrosis in 84% of the patients.The WHO guidelines proposed cut-offs might be higher for HBeAg-negative CHB patients with ALT ≤2 ULN, and might underestimate the proportion of significant fibrosis and cirrhosis. A new set of cut-offs should be used to predict significant fibrosis and cirrhosis in this specific population.

Immune response- and viral control-related pathways in the progression of chronic hepatitis B

BACKGROUND

Chronic hepatitis B (CHB) is a complicated and dynamic course, and is associated with advanced liver disease. Host immune response against viral infection plays a pivotal role in the progression of CHB. However, it is still uncharted that how the hepatic transcriptomes in patients with CHB are correlated with the clinical phases.

OBJECTIVE

This study aimed to identify the specific sub-networks across various phases of CHB and infer potential pathways for phenotypic outcome prediction.

METHODS

In this study, we performed the pairwise comparisons of the hepatic transcriptomes of CHB patients under different phases, and constructed the differential co-expression networks (DCNs). We firstly identified the critical genes from each DCN according to the adjacency matrix of the network. Then, the specific sub-networks were digged by iteratively affiliating genes that can increase the classification accuracy, using a snow-ball sampling strategy. Permutation test was implemented to determine the statistical significance of these sub-networks. Finally, each sub-network was given a most significant functional pathway.

RESULTS

We constructed 3 DCNs by pairwise comparing the hepatic transcriptomes among three CHB phases, and systemically tracked 1, 1 and 2 specific sub-networks and pathways, respectively. Relative to immune tolerant phase, TGF-beta receptor signaling in EMT (epithelial to mesenchymal transition) pathway was significantly changed in the immune clearance phase, and nuclear receptor transcription pathway and adenylate cyclase activating pathway were altered in inactive carrier state. The host genes related to DNA strand elongation showed significant difference between the immune clearance phase and inactive carrier state.

CONCLUSIONS

By pairwise comparing the hepatic transcriptomes of CHB patients under a network view, several immune- and viral control-related pathways were identified in this study. These results might serve as a foundation for characterizing the host transcriptomes responded to CHB infection, and hold clues for the development of potential targets for disease control.

High serum resistin associates with intrahepatic inflammation and necrosis: an index of disease severity for patients with chronic HBV infection

BACKGROUND

Studies have revealed that resistin plays a role as an intrahepatic cytokine with proinflammatory activities. This study investigated the association between serum resistin and fibrosis severity and the possible marker role of resistin in the inflammatory process of chronic hepatitis B.

METHODS

In this study, 234 subjects with HBV infection were retrospectively selected, including 85 patients with chronic hepatitis B (CHB), 70 patients with HBV-related liver cirrhosis (LC-B), and 79 patients with HBV-related liver failure (LF-B). Serum levels of resistin, IL-1, IL-6, IL-17, IL-23, TNF-α, and TGF-β1 were assayed by ELISA. Demographic and clinical characteristics of patients were extracted from clinical databases of Taihe Hospital, Hubei University of Medicine, including serum levels of alanine aminotransferase (ALT), aspartate aminotransferase (AST), total bilirubin (TBil), and liver stiffness (LS).

RESULTS

All the selected patients with HBV infection showed significantly increased levels of serum resistin, which was rarely detectable in the healthy controls. Serum resistin levels in patients with CHB, LC-B, and LF-B were 4.119 ± 5.848 ng/mL, 6.370 ± 6.834 ng/mL, and 6.512 ± 6.076 ng/mL, respectively. Compared with the CHB group, patients with LC-B or LF-B presented with significantly higher serum levels of resistin (p < 0.01). On the other hand, all of the enrolled patients had high serum levels of IL-1, IL-6, IL-17, TNF-α, and TGF-β1, but not IL-23. Interestingly, serum levels of resistin was significantly positively correlated with serum levels of TGF-β1 in LC-B patients (R = 0.3090, p = 0.0290), with IL-17 in LC-B (R = 0.4022, p = 0.0038) and LF-B patients (R = 0.5466, p < 0.0001), and with AST (R = 0.4501, p = 0.0036) and LS (R = 0.3415, p = 0.0310) in CHB patients.

CONCLUSIONS

High serum resistin associates with intrahepatic inflammation and necrosis and may be used as an index of disease severity for patients with chronic HBV infection.

The gamma-glutamyl transpeptidase-to-platelet ratio predicts liver fibrosis and cirrhosis in HBeAg-positive chronic HBV infection patients with high HBV DNA and normal or mildly elevated alanine transaminase levels in China

The gamma-glutamyl transpeptidase-to-platelet ratio (GPR) is a new serum diagnostic model, which is reported to be more accurate than aspartate transaminase-to-platelet ratio index (APRI) and fibrosis index based on the four factors (Fib-4) for the diagnosis of significant fibrosis and cirrhosis in chronic HBV infection (CHBVI) patients in West Africa. To evaluate the performance of the GPR model for the diagnosis of liver fibrosis and cirrhosis in HBeAg-positive CHBVI patients with high HBV DNA (≥5 log₁₀ copies/mL) and normal or mildly elevated alanine transaminase (ALT) (≤2 times upper limit of normal (ULN)) in China. A total of 1521 consecutive CHBVI patients who underwent liver biopsies and routine laboratory tests were retrospectively screened. Of these patients, 401 treatment naïve HBeAg-positive patients with HBV DNA≥5 log₁₀ copies/mL and ALT≤2 ULN were included. The METAVIR scoring system was adopted as the pathological diagnosis standard of liver fibrosis. Using liver histology as a gold standard, the performances of GPR, APRI, and Fib-4 for the diagnosis of liver fibrosis and cirrhosis were evaluated and compared by receiver operating characteristic (ROC) curves and the area under the ROC curves (AUROCs). Of 401 patients, 121 (30.2%), 49 (12.2%) and 17 (4.2%) were classified as having significant fibrosis (≥F2), severe fibrosis (≥F3) and cirrhosis (=F4), respectively. After estimating the AUROC to predict significant fibrosis, the performance of GPR (AUROC=0.66, 95% CI 0.60-0.72) was higher than APRI (AUROC=0.58, 95% CI 0.52-0.64, P=.002) and Fib-4 scores (AUROC=0.54, 95% CI 0.47-0.60, P<.001). After estimating the AUROC to predict severe fibrosis, the performance of GPR (AUROC=0.71, 95% CI 0.63-0.80) was also higher than APRI (AUROC=0.65, 95% CI 0.56-0.73, P=.003) and Fib-4 scores (AUROC=0.67, 95% CI 0.58-0.75, P=.001). After estimating the AUROC to predict cirrhosis, the performance of GPR (AUROC=0.73, 95% CI 0.56-0.88) was higher than APRI (AUROC=0.69, 95% CI 0.54-0.83, P=.041) and Fib-4 scores (AUROC=0.69, 95% CI 0.55-0.82, P=.012) too. The GPR is a new serum model for the diagnosis of liver fibrosis and cirrhosis and shows obvious advantages in Chinese HBeAg-positive patients with HBV DNA≥5 log₁₀ copies/mL and ALT≤2 ULN compared with APRI and Fib-4, thus warranting its widespread use for this specific population.

New horizon for radical cure of chronic hepatitis B virus infection

About 250 to 350 million people worldwide are chronically infected with hepatitis B virus (HBV), and about 700000 patients per year die of HBV-related cirrhosis or hepatocellular carcinoma (HCC). Several anti-viral agents, such as interferon and nucleos(t)ide analogues (NAs), have been used to treat this disease. NAs especially have been shown to strongly suppress HBV replication, slowing the progression to cirrhosis and the development of HCC. However, reactivation of HBV replication often occurs after cessation of treatment, because NAs alone cannot completely remove covalently-closed circular DNA (cccDNA), the template of HBV replication, from the nuclei of hepatocytes. Anti-HBV immune responses, in conjunction with interferon-γ and tumor necrosis factor-α, were found to eliminate cccDNA, but complete eradication of cccDNA by immune response alone is difficult, as shown in patients who recover from acute HBV infection but often show long-term persistence of small amounts of HBV-DNA in the blood. Several new drugs interfering with the life cycle of HBV in hepatocytes have been developed, with drugs targeting cccDNA theoretically the most effective for radical cure of chronic HBV infection. However, the safety of these drugs should be extensively examined before application to patients, and combinations of several approaches may be necessary for radical cure of chronic HBV infection.

Favorable Long-Term Oncologic Outcomes of Hepatocellular Carcinoma Following Laparoscopic Liver Resection

BACKGROUND

Reports on the long-term oncologic outcomes of laparoscopic liver resection (LLR) compared to open liver resection (OLR) in patients with hepatocellular carcinoma (HCC) are rare. The aim of this study was to compare the long-term outcomes of LLR and OLR as a treatment for HCC patients.

PATIENTS AND METHODS

A total of 125 patients were included in the study (32 patients underwent LLR and 93 underwent OLR). Data were categorized according to operation methods. The primary endpoints were disease-free survival and overall survival. The secondary endpoints were surgical outcomes of LLR for HCC.

RESULTS

Capsular invasion was more frequent in the LLR group (P = .001). The median follow-up period was 48 months (1-188 month). There were no significant differences between the two groups regarding mortality and morbidity. Hospitalization days were shorter in the LLR group (P = .042). Disease-free 5-year survival of HCC was 40.9% and 47.2% in the LLR and OLR group, respectively (P = .376). Overall 5-year survival for HCC was 96.4% and 96.7% for the LLR and OLR group, respectively (P = .748).

CONCLUSION

Our long-term analysis on oncologic aspects confirms the safety of LLR compared to OLR in HCC patients.

Complete Genome Sequence of Hepatitis B Virus Genotype E, the First Molecular Characterization from an Imported Case in Mexico

Hepatitis B virus infection is currently a global public health problem. Here, we present the first characterization and complete genome sequence of a strain belonging to genotype E in Mexico, obtained from a foreign carrier with chronic infection.