Hepatitis B virus (HBV) induces the expression of interleukin-8 that in turn reduces HBV sensitivity to interferon-alpha

Interleukin-8 in HepG2 cells: Enhancing antiviral proteins in uninfected cells but promoting HBV replication in infected cells

In vitro studies have revealed that hepatitis B virus (HBV) infection upregulates interleukin-8 (IL-8), which enhances HBV replication. Clinically, elevated IL-8 levels in chronic HBV patients are associated with diminished therapeutic efficacy of interferon-α (IFN-α). Our study advances these findings by demonstrating that IL-8 promotes the expression of myxovirus resistance A (MxA) and protein kinase R (PKR) in HepG2 cells via the PI3K-AKT pathway. However, HBV-infected cells fail to exhibit IL-8-induced upregulation of MxA and PKR, likely due to HBV's upregulation of PP2A that inhibits the PI3K-AKT pathway. Notably, IL-8 targets the C/EBPα transcription factor, increasing HBV promoter activity and viral replication, which in turn partially suppresses the expression of MxA and PKR induced by IFN-α. Our findings uncover a mechanism by which HBV may evade immune responses, suggesting potential new strategies for immunotherapy against chronic HBV infection.

Modulation of monocyte activity by hepatocellular MicroRNA delivery through HBsAg particles: Implications for pathobiology of chronic hepatitis B

BACKGROUND AND AIMS

HBsAg serves as an important immune-modulatory factor in chronic hepatitis B. One aspect of such modulation may act through monocytes, which are the major Ag-presenting cells taking up HBsAg. There is evidence for the encapsulation of hepatocellular microRNAs (miRNAs) by HBsAg particles, while its pathobiological significance is unclear. Here, we characterized the miRNA profile in patients with chronic hepatitis B and probed their association with liver inflammation.

APPROACHES AND RESULTS

We collected plasma from patients that are treatment-naive with chronic hepatitis B (n = 110) and quantified total/HBsAg-enveloped miRNAs by qRT-PCR and plasma cytokines by ELISA. The biological effects of HBsAg-delivered miRNAs in monocytes were evaluated using multiple approaches. The clinical significance of candidate miRNAs and cytokines was corroborated in patients with HBV-associated advanced liver diseases. The plasma miRNA profile showed 2 major clusters, one significantly associated with HBsAg titer and the other correlated with liver inflammation. Among HBsAg-carried miRNAs, miR-939 displayed the most significant correlation with IL-8. Mechanistically, miR-939 in subviral particles enters monocytes and significantly augments IL-8 production through the mitogen-activated protein kinase (MAPK) p38 signaling pathway. Finally, the findings that miR-939 positively correlated with IL-8 level and inflammation/fibrosis stage in the cohort of HBV-associated advanced liver diseases support its causative role in the progression of liver diseases.

CONCLUSIONS

HBsAg particles carry hepatocellular miRNAs, including miR-939, which enter monocytes and alter their functional status, such as IL-8 secretion. Our findings demonstrate that the HBsAg-miR-939-IL-8 axis may play a crucial role in HBV-induced hepatic necro-inflammation and the progression of advanced liver diseases.

Changes in Serum Interleukin-8 Levels Predict Response to Immune Checkpoint Inhibitors Immunotherapy in Unresectable Hepatocellular Carcinoma Patients

Background

Effective biomarkers are needed to predict the efficacy of immune checkpoint inhibitors (ICIs) therapy in hepatocellular carcinoma (HCC). We evaluated the early changes in serum interleukin-8 (IL-8) levels as a biomarker of response to ICIs in patients with unresectable HCC.

Methods

Eighty patients who received ICIs therapy alone or in combination with other treatments for unresectable HCC were included. Serum was collected at baseline and 2-4 weeks after the first dose. Serum IL-8 levels were measured using by ELISA.

Results

In the progressive disease (PD) group, serum IL-8 levels increased significantly before the second dose of ICIs therapy compared with baseline levels (P < 0.001). Early changes in serum IL-8 levels were significantly associated with the response to ICIs therapy (P < 0.001). A cutoff value of 8.1% increase over the baseline most effectively predicted the response to ICIs. Increases in serum IL-8 levels > 8.1% indicated the uselessness of ICIs immunotherapy in patients with unresectable HCC. Patients with increases in serum IL-8 levels > 8.1% had significantly shorter overall survival (OS) and progression-free survival (PFS) than those with increases in serum IL-8 levels ≤ 8.1% (P < 0.001). Increases in serum IL-8 levels > 8.1% were independent prognosticators of worse OS (P = 0.003) and PFS (P < 0.001).

Conclusion

Early changes in serum IL-8 levels, measured only 2-4 weeks after starting therapy, could predict the response to ICIs therapy, as well as OS and PFS of patients with unresectable HCC. Increases in serum IL-8 levels > 8.1% indicated the uselessness of ICIs immunotherapy and predicted worse OS and PFS.

Expression of 10 circulating cytokines/chemokines in HBV-related liver disease

BACKGROUND

Cytokines/chemokines play essential roles in the occurrence and progression of hepatitis B virus (HBV) infection. This study aimed to observe the expression patterns of 10 related cytokines/chemokines in the serum of healthy individuals, self-limited patients and HBV-infected patients at different stages of disease (chronic hepatitis B (CHB), liver cirrhosis (LC), hepatocellular dysplastic nodules (DNs) and hepatocellular carcinoma (HCC)) and to analyze the relationships of these cytokines/chemokines with disease progression.

METHODS

The levels of six cytokines (FGF-2, IFN-α2, IL-4, IL-6, IL-10 and VEGF-A) and four chemokines (GRO-α, IL-8, IP-10 and MCP-1) were quantified using Luminex multiplex technology.

RESULTS

There were no significant differences in the expression of the 10 cytokines/chemokines between healthy individuals and self-limited patients. The levels of IL-4, IL-6, and IL-8 increased significantly in the CHB and LC groups. IL-10 was highly expressed in the HCC group. The level of IP-10 was significantly greater in all liver disease groups (CHB, LC, DN and HCC) than in the HI and SL-HBV groups, while the level of GRO was significantly lower in all liver disease groups than in the HI and SL-HBV groups. The levels of the 10 cytokines/chemokines were not significantly different between the preoperative group and the two-day postoperative group. Significant increases in the levels of IL-4, VEGF-A and IL-8 and significant decreases in those of IL-10 and GRO-α were observed 3 months after surgery. Correlation analysis revealed that most of the cytokines/chemokines with significant correlation differences were positively correlated before and after HCC surgery.

CONCLUSION

Our results highlight the fluctuating status of specific cytokines in HBV infection-related disease progression. It is speculated that these cytokines may be used as serum markers to monitor dynamic changes during the progression of HBV-related liver disease and to predict patient prognosis.

Interferon-α induces differentiation of cancer stem cells and immunosuppression in hepatocellular carcinoma by upregulating CXCL8 secretion

Interferon-alpha (IFN-α) is widely used in the clinical treatment of patients with chronic hepatitis B and hepatocellular carcinoma (HCC). However, high levels of CXCL8 are associated with resistance to IFN-α therapy and poorer prognosis in advanced cancers. In this study, we investigated whether IFN-α could directly induce the production of CXCL8 in HCC cells and whether CXCL8 could antagonize the antitumor activity of IFN-α. We found that IFN-α not only upregulated the expression of the inducible genes CXCL9, CXCL10, CXCL11 and PD-L1, but also significantly stimulated CXCL8 secretion in HCC cells. Mechanically, IFN-α induces CXCL8 expression by activating the AKT and JNK pathways. In addition, our results demonstrate that IFN-α exposure significantly increases the differentiation of HCC stem cells, but this effect is reversed by the addition of the CXCL8 receptor CXCR1/2 inhibitor Reparixin and STAT3 inhibitor Stattic. Besides, our study reveals that the cytokine CXCL8 secreted by IFN-α-induced HCC cells inhibits T-cell function. Conversely, inhibition of CXCL8 promotes TNF-α and IFN-γ secretion by T cells. Finally, liver cancer patients who received anti-PD-1/PD-L1 immunotherapy with high CXCL8 expression had a lower immunotherapy efficacy. Overall, our findings clarify that IFN-α triggers immunosuppression and cancer stem cell differentiation in hepatocellular carcinoma by upregulating CXCL8 secretion. This discovery provides a novel approach to enhance the effectiveness of HCC treatment in the future.

The Comparison of Serum Interleukin-8 Levels Based on Severity of Liver Cirrhosis

Background

The molecule known as Interleukin-8 (IL-8), a chemotactic leukocyte, has been found to have a crucial role in the perpetuation of the inflammatory environment that is associated with hepatitis B virus (HBV) infection, as well as in the development of liver cirrhosis and cancer.

Objective

The aim of this study was to carefully examine the role of IL-8 in the inflammatory reaction and to compare the levels based on the severity of liver cirrhosis.

Methods

The study was conducted from February 2018 to September 2018 at the Gastroenterohepatology Division, Internal medicine Department, Faculty of Medicine, Universitas Sumatera Utara. The study was designed as an analytic comparative, cross-sectional study. The liver cirrhosis patients who participated in this study met the inclusion criteria and provided informed consent.

Results

A total of 70 patients were included in the study, from which we identified 1 individual with child-pugh A, 28 individuals with child-pugh B, and 41 individuals with child-pugh C. The serum level of IL-8 was found to be 98 (11-320) (pg/ml). The IL-8 levels between child-pugh B and C patients did not exhibit any noteworthy differences during our analysis (p = 0.109, p>0.05).

Conclusion

There is no notable inequality in the levels of IL-8 across different stages of liver cirrhosis.

Association between hepatitis B virus replication during pregnancy and perinatal outcomes: a retrospective cohort study

BACKGROUND

The effect of hepatitis B virus (HBV) replication during pregnancy on the outcomes of pregnancies remains to be elucidated.

OBJECTIVES

This study aimed to investigate the association between HBV replication and adverse maternal and infant outcomes.

METHODS

We retrospectively analysed the clinical data of 836 pregnant inpatients with hepatitis B surface antigen positivity who delivered at two provincial tertiary grade A hospitals in the Fujian province between June 2016 and October 2020.

RESULTS

The incidence of intrahepatic cholestasis of pregnancy, hypertensive syndrome complicating pregnancy, gestational diabetes mellitus, preterm birth, macrosomia, growth restriction, and vaginal infections did not differ in the HBV replication and non-replication groups (p > 0.05); however, the rates of caesarean section (p = 0.017; OR, 1.423; 95% CI, 1.065-1.902) and neonatal jaundice (p < 0.001; OR, 2.361; 95% CI, 1.498-3.721) were higher in the replication group than that in the non-replication group. After using propensity score analysis to adjust for alanine transaminase and aspartate aminotransferase levels in both groups, the replication group was still found to have an increased risk for caesarean section (p < 0.001; OR, 2.367; 95% CI, 1.668-3.359) and their infants had higher rates of neonatal jaundice (p < 0.001; OR, 12.605; 95% CI, 4.456-35.656).

CONCLUSIONS

Our findings contribute to a better understanding of the association between maternal HBV replication status and perinatal outcomes. Pregnant women with HBV replication face an increased risk of caesarean section, and their infants appear to have a higher risk for neonatal jaundice.

Transcriptomic analysis of sorted lung cells revealed a proviral activity of the NF-κB pathway toward SARS-CoV-2

Investigations of cellular responses to viral infection are commonly performed on mixed populations of infected and uninfected cells or using single-cell RNA sequencing, leading to inaccurate and low-resolution gene expression interpretations. Here, we performed deep polyA+ transcriptome analyses and novel RNA profiling of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infected lung epithelial cells, sorted based on the expression of the viral spike (S) protein. Infection caused a massive reduction in mRNAs and long non-coding RNAs (lncRNAs), including transcripts coding for antiviral factors, such as interferons (IFNs). This absence of IFN signaling probably explained the poor transcriptomic response of bystander cells co-cultured with S+ ones. NF-κB pathway and the inflammatory response escaped the global shutoff in S+ cells. Functional investigations revealed the proviral function of the NF-κB pathway and the antiviral activity of CYLD, a negative regulator of the pathway. Thus, our transcriptomic analysis on sorted cells revealed additional genes that modulate SARS-CoV-2 replication in lung cells.

Coronavirus Porcine Epidemic Diarrhea Virus Utilizes Chemokine Interleukin-8 to Facilitate Viral Replication by Regulating Ca2+ Flux

Chemokine production by epithelial cells is crucial for neutrophil recruitment to sites of inflammation during viral infection. However, the effect of chemokine on epithelia and how chemokine is involved in coronavirus infection remains to be fully understood. Here, we identified an inducible chemokine interleukin-8 (CXCL8/IL-8), which could promote coronavirus porcine epidemic diarrhea virus (PEDV) infection in African green monkey kidney epithelial cells (Vero) and Lilly Laboratories cell-porcine kidney 1 epithelial cells (LLC-PK1). IL-8 deletion restrained cytosolic calcium (Ca2+), whereas IL-8 stimulation improved cytosolic Ca2+. The consumption of Ca2+ restricted PEDV infection. PEDV internalization and budding were obvious reductions when cytosolic Ca2+ was abolished in the presence of Ca2+ chelators. Further study revealed that the upregulated cytosolic Ca2+ redistributes intracellular Ca2+. Finally, we identified that G protein-coupled receptor (GPCR)-phospholipase C (PLC)-inositol trisphosphate receptor (IP3R)-store-operated Ca2+ (SOC) signaling was crucial for enhancive cytosolic Ca2+ and PEDV infection. To our knowledge, this study is the first to uncover the function of chemokine IL-8 during coronavirus PEDV infection in epithelia. PEDV induces IL-8 expression to elevate cytosolic Ca2+, promoting its infection. Our findings reveal a novel role of IL-8 in PEDV infection and suggest that targeting IL-8 could be a new approach to controlling PEDV infection. IMPORTANCE Coronavirus porcine epidemic diarrhea virus (PEDV) is a highly contagious enteric coronavirus that caused severe economic losses worldwide, and more effort is needed to develop economical and efficient vaccines to control or eliminate this disease. The chemokine interleukin-8 (CXCL8/IL-8) is indispensable for the activation and trafficking of inflammatory mediators and tumor progression and metastasis. This study evaluated the effect of IL-8 on PEDV infection in epithelia. We found that IL-8 expression improved cytosolic Ca2+ in epithelia, facilitating PEDV rapid internalization and egress. G protein-coupled receptor (GPCR)-phospholipase C (PLC)-inositol trisphosphate receptor (IP3R)-SOC signaling was activated by IL-8, releasing the intracellular Ca2+ stores from endoplasmic reticulum (ER). These findings provide a better understanding of the role of IL-8 in PEDV-induced immune responses, which will help develop small-molecule drugs for coronavirus cure.

The antiviral activity of tripartite motif protein 38 in hepatitis B virus replication and gene expression and its association with treatment responses during PEG-IFN-α antiviral therapy

Hepatitis B virus (HBV) infection represents one of the most critical health problems worldwide. Tripartite motif protein 38 (TRIM38) is an interferon-stimulated gene (ISG) that inhibits various DNA and RNA viruses.In this study, we found a mechanistic correlation between TRIM38 expression levels and the efficacy of HBV infection and IFN-α therapy in patients with CHB. TRIM38 was highly induced by IFN-alpha (IFN-α) in vivo and in vitro. TRIM38 overexpression inhibited HBV replication and gene expression in HepG2 and HepG2.2.15 cells, whereas knockdown of TRIM38 increased these processes. Further experiments indicated that TRIM38 protein enhanced the antiviral effect of IFN-α by enhancing the expression of antiviral proteins. A prospective study revealed high TRIM38 levels in peripheral blood PBMCs were from early responders, and increased TRIM38 expression correlated with a better response to PEG-IFN-α therapy. Taken together, our study suggests that TRIM38 plays a vital role in HBV replication and gene expression.

CXCL8, CXCL9, CXCL10, and CXCL11 as biomarkers of liver injury caused by chronic hepatitis B

Background

Chronic hepatitis B (CHB) remains a significant global health problem, leading to recurrent inflammation and liver-damaging diseases such as fibrosis, cirrhosis, and hepatocellular carcinoma (HCC). Currently, although diagnostic markers for CHB are well established, the indicators for predicting liver injury caused by hepatitis B virus (HBV) infection still need to be further explored. Thus, the identification of credible infectious indicators is urgently needed to facilitate timely clinical intervention and avoid the progression of disease malignancy.

Methods

The Gene Expression Omnibus (GEO) database GSE83148 data set was used to explore the hub genes for HBV infection. The quantitative real-time polymerase chain reaction (qPCR) was used to identify the impact of HBV infection on the expression of hub gene at the cell level. At the same time, serum samples and clinical information were collected from healthy, HBV-free and CHB patients. The enzyme-linked immunosorbent assay (ELISA) was used to verify the results of cell experiments and Pearson correlation analysis was used to clarify hub genes correlation with HBV infection indicators and liver injury-related indicators. Finally, the Gene Expression Profiling Interactive Analysis (GEPIA) database was used to analyze the differences in the expression of hub gene in liver injury diseases.

Results

Chemokine (C-X-C motif) ligand (CXCL)8, CXCL9, CXCL10, and CXCL11 were identified as hub genes in HBV infection. After HBV infection, the expression of the four chemokines was significantly increased and the concentrations secreted into serum were also increased. Moreover, the four chemokines were significantly correlated with HBV infection-related indicators and liver injury-related indicators, which were positively correlated with alanine aminotransferase (ALT), aspartate aminotransferase (AST) and hepatitis B e antigen (HBeAg), and negatively correlated with AST/ALT ratio and hepatitis B core antibody (HBcAb). In addition, the expression of CXCL9, CXCL10, and CXCL11 in HCC tissues was significantly higher than in normal tissues.

Conclusion

Using a combination of bioinformatics, cell experiments, and clinical correlation analysis, this study showed that CXCL8, CXCL9, CXCL10, and CXCL11 can be used as serum biomarkers to forecast liver injury caused by HBV infection.

Hepatitis B Flare in Hepatitis B e Antigen-Negative Patients: A Complicated Cascade of Innate and Adaptive Immune Responses

Chronic hepatitis B virus (HBV) infection is a dynamic process involving interactions among HBV, hepatocytes, and the host immune system. The natural course of chronic hepatitis B (CHB) is divided into four chronological phases, including the hepatitis B e antigen (HBeAg)-positive and HBeAg-negative phases. During HBV flare, alanine aminotransferase (ALT) levels abruptly rise to >5× the upper limit of normal; this is thought to occur due to the immune response against an upsurge in serum HBV DNA and antigen levels. Hepatitis flares may occur spontaneously, during or after antiviral therapy, or upon immunosuppression or chemotherapy in both HBeAg-positive and HBeAg-negative patients. The clinical spectrum of HBV flares varies from asymptomatic to hepatic decompensation or failure. HBeAg seroconversion with ≥ 1 year of consolidation therapy is accepted as an endpoint of oral antiviral therapy in HBeAg-positive patients, but recommendations for treating HBeAg-negative patients differ. Thus, the management of HBeAg-negative patients has attracted increasing interest. In the current review, we summarize various types of HBV flares and the associated complex cascade of innate and adaptive immune responses, with a focus on HBeAg-negative CHB patients. Hopefully, this review will provide insight into immunopathogenesis to improve the management of HBV flares in HBeAg-negative CHB patients.

Suppression of Interferon-α Treatment Response by Host Negative Factors in Hepatitis B Virus Infection

Chronic hepatitis B virus (CHB) infection remains a major global public health issue for which there is still lacking effective curative treatment. Interferon-α (IFN-α) and its pegylated form have been approved as an anti-HBV drug with the advantage of antiviral activity and host immunity against HBV infection enhancement, however, IFN-α treatment failure in CHB patients is a challenging obstacle with 70% of CHB patients respond poorly to exogenous IFN-α treatment. The IFN-α treatment response is negatively regulated by both viral and host factors, and the role of viral factors has been extensively illustrated, while much less attention has been paid to host negative factors. Here, we summarized evidence of host negative regulators and parameters involved in IFN-α therapy failure, review the mechanisms responsible for these effects, and discuss the possible improvement of IFN-based therapy and the rationale of combining the inhibitors of negative regulators in achieving an HBV cure.

The Genetic Profile and Serum Level of IL-8 Are Associated with Chronic Hepatitis B and C Virus Infection

The present study evaluated the IL8-251 A/T polymorphism in samples from 74 patients with chronic hepatitis B (HBV), 100 patients with chronic hepatitis C (HCV), and 300 healthy donors (CG). The correlations of this polymorphism with plasma IL-8 and disease stage were calculated. Polymorphisms were identified by real-time PCR. IL-8 was measured by enzyme-linked immunosorbent assay. The IL8-251 A/T genotype was not associated with susceptibility to infection by HBV or HCV. The wild-type allele (A) was associated with higher levels of inflammation (p = 0.0464) and fibrosis scores (p = 0.0016) in the HBV group, representing an increased risk for increased inflammatory activity (OR = 1.84; p = 0.0464) and for high fibrosis scores (OR = 2.63; p = 0.0016). Viral load was higher in HBV patients with polymorphic genotypes (TA and TT) at the IL8-251 A/T polymorphism than in those with the wild-type genotype (p = 0.0272 and p = 0.0464, respectively). Plasma IL-8 was higher among patients infected with HBV or HCV than in the control group (p = 0.0445 and p = 0.0001, respectively). The polymorphic genotype was associated with lower IL-8 than the wild-type genotype in the HBV group (p = 0.0239) and the HCV group (p = 0.0372). The wild-type genotype for IL8-251 A/T and high IL-8 were associated with a worse prognosis for infections; therefore, they may contribute to viral persistence and the development of more severe forms of chronic viral liver diseases.

Are Humanized Mouse Models Useful for Basic Research of Hepatocarcinogenesis through Chronic Hepatitis B Virus Infection?

Chronic hepatitis B virus (HBV) infection is a global health problem that can lead to liver dysfunction, including liver cirrhosis and hepatocellular carcinoma (HCC). Current antiviral therapies can control viral replication in patients with chronic HBV infection; however, there is a risk of HCC development. HBV-related proteins may be produced in hepatocytes regardless of antiviral therapies and influence intracellular metabolism and signaling pathways, resulting in liver carcinogenesis. To understand the mechanisms of liver carcinogenesis, the effect of HBV infection in human hepatocytes should be analyzed. HBV infects human hepatocytes through transfer to the sodium taurocholate co-transporting polypeptide (NTCP). Although the NTCP is expressed on the hepatocyte surface in several animals, including mice, HBV infection is limited to human primates. Due to this species-specific liver tropism, suitable animal models for analyzing HBV replication and developing antivirals have been lacking since the discovery of the virus. Recently, a humanized mouse model carrying human hepatocytes in the liver was developed based on several immunodeficient mice; this is useful for analyzing the HBV life cycle, antiviral effects of existing/novel antivirals, and intracellular signaling pathways under HBV infection. Herein, the usefulness of human hepatocyte chimeric mouse models in the analysis of HBV-associated hepatocarcinogenesis is discussed.

Antiviral Activity of Interferon Alpha-Inducible Protein 27 Against Hepatitis B Virus Gene Expression and Replication

Despite the availability of effective vaccines, hepatitis B virus (HBV) is still a major health issue, and approximately 350 million people have been chronically infected with HBV throughout the world. Interferons (IFNs) are the key molecules in the innate immune response that restrict several kinds of viral infections via the induction of hundreds of IFN-stimulated genes (ISGs). The objective of this study was to confirm if interferon alpha-inducible protein 27 (IFI27) as an ISG could inhibit HBV gene expression and DNA replication both in cell culture and in a mouse model. In human hepatoma cells, IFI27 was highly induced by the stimulation of IFN-alpha (IFN-α), and it potentiated the anti-HBV activity. The overexpression of IFI27 inhibited, while its silencing enhanced the HBV replication in HepG2 cell. However, the knocking out of IFI27 in HepG2 cells robustly increases the formation of viral DNA, RNA, and proteins. Detailed mechanistic analysis of the HBV genome showed that a sequence [nucleotide (nt) 1715-1815] of the EnhII/Cp promoter was solely responsible for viral inhibition. Similarly, the hydrodynamic injection of IFI27 expression constructs along with the HBV genome into mice resulted in a significant reduction in viral gene expression and DNA replication. In summary, our studies suggested that IFI27 contributed a vital role in HBV gene expression and replication and IFI27 may be a potential antiviral agent for the treatment of HBV.

Hepatitis B-Induced IL8 Promotes Hepatocellular Carcinoma Venous Metastasis and Intrahepatic Treg Accumulation

Hepatitis B-associated hepatocellular carcinoma (HCC) is often accompanied by severe vascular invasion and portal vein tumor thrombus, leading to a poor prognosis. However, the underlying mechanism of this disease remains obscure. In this study, we demonstrate that the hepatitis B virus (HBV)-encoded gene HBx induces high IL8 production through MEK-ERK signal activation, leading to enhanced endothelial permeability to facilitate tumor vascular invasion. In a vascular metastatic model using a tail vein injection in a transgenic mouse with selective expression of human CXCR1 in the endothelium, activation of the IL8-CXCR1 cascade by overexpression of IL8 in tumor cells dramatically enhanced liver metastasis. Mechanistically, IL8 selectively induced GARP-latent-TGFβ in liver sinusoidal endothelial cells and subsequently provoked preferential regulatory T-cell polarization to suppress antitumor immunity. Collectively, these findings reveal a hepatitis B-associated IL8-CXCR1 signaling axis that mediates vascular invasion and local microenvironmental immune escape of HCC to induce intrahepatic metastasis, which may serve as potential therapeutic targets for HBV-associated HCC. SIGNIFICANCE: This study identifies a hepatitis B-induced IL8/CXCR1/TGFβ signaling cascade that suppresses antitumor immunity and enhances metastasis in hepatocellular carcinoma, providing new potential targets for therapeutic intervention.

A Network Pharmacology Approach to Explore the Mechanisms of Artemisiae scopariae Herba for the Treatment of Chronic Hepatitis B

Background

As a traditional Chinese medicine, Artemisiae scopariae Herba (ASH) is used to treat various liver diseases. The purpose of this study was to explore the mechanisms of ASH for treating chronic hepatitis B (CHB) using a network pharmacological method.

Methods

Bioactive ingredients and related targets of ASH were obtained from Traditional Chinese Medicine Systems Pharmacology (TCMSP) database. Gene names of targets were extracted from UniProt database. Differentially expressed genes (DEGs) of CHB were obtained from microarray dataset GSE83148. The intersect genes between DEGs and target genes were annotated using clusterProfiler package. The STRING database was used to obtain a network of protein-protein interactions. Cytoscape 3.7.2 was used to construct the “ingredient-gene-pathway” (IGP) network. Molecular docking studies were performed using Autodock vina.

Results

A total of 13 active components were extracted from TCMSP database. Fifteen intersect genes were obtained between 183 target genes and 403 DEGs of GSE83148. Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis results showed that ASH against CHB mainly involved in toll-like receptor signaling pathway, cellular senescence, hepatitis B, and chemokine signaling pathway. We screened one hub compound, five core targets, and four key pathways from constructed networks. The docking results indicated the strong binding activity between quercetin and AKT1.

Conclusions

This study provides potential molecular mechanisms of ASH against CHB based on exploration of network pharmacology.

Factors influencing PCV13 specific antibody response in Danish children starting in day care

This study examines different factors influencing the 13-valent pneumococcal conjugate vaccine (PCV13) specific antibody response in 8–13 months old Danish children starting in day care. We present secondary findings to the ProbiComp study, which included nose swabs, buccal swabs and blood samples from the children before entering day care (baseline) and again after 6 months. Pneumococci isolated from nose swabs were identified by latex agglutination kit and Quellung reaction. Luminex-based assay was used for antibody measurements against specific anti-pneumococcal capsular IgG. Buccal gene expression was analyzed by qPCR. Statistical analyses were performed in R and included Pearson’s Chi-squared test, Welch two sample t-test and linear regression models. The PCV13 antibody response was unaffected by whether the children were carriers or non-carriers of any pneumococcal serotype. Having siblings increased the risk of carrying serotype 21 before day care (p = 0.020), and having siblings increased the PCV13 antibody response at the end of study (p = 0.0135). Hepatitis B-vaccination increased the PCV13 antibody response before day care attendance (p = 0.005). The expression of IL8 and IL1B was higher in children carrying any pneumococcal serotype at baseline compared to non-carriers (p = 0.0125 and p = 0.0268 respectively).

The AP-1 pathway; A key regulator of cellular transformation modulated by oncogenic viruses

Cancer progression is critically associated with modulation of host cell signaling pathways. Activator protein-1 (AP-1) signaling is one such pathway whose deregulation renders the host more susceptible to cancer development. Oncogenic viruses, including hepatitis B virus, hepatitis C virus, human papilloma virus, Epstein-Barr virus, human T-cell lymphotropic virus type 1, and Kaposi's sarcoma-associated herpes virus, are common causes of cancer. This review discusses how these oncoviruses by acting through various aspects of the host cell signaling machinery such as the AP-1 pathway might affect oncoviral tumorigenesis, replication, and pathogenesis. The review also briefly considers how the pathway might be targeted during infections with these oncogenic viruses.

Harmonized Autophagy Versus Full-Fledged Hepatitis B Virus: Victorious or Defeated

Autophagy is a finely tuned process in the regulation of innate immunity to avoid excessive inflammatory responses and inflammasome signaling. In contrast, the results of recent studies have shown that autophagy may disease-dependently contribute to the pathogenesis of liver diseases, such as fibrosis, cirrhosis, and hepatocellular carcinoma (HCC) during hepatitis B virus (HBV) infection. HBV has learned to subvert the cell's autophagic machinery to promote its replication. Given the great impact of the autophagy mechanism on the HBV infection and HCC, recognizing these factors may be offered new hope for human intervention and treatment of chronic HBV. This review focuses on recent findings viewing the dual role of autophagy plays in the pathogenesis of HBV infected hepatocytes.

Immunological biomarkers as indicators for outcome after discontinuation of nucleos(t)ide analogue therapy in patients with HBeAg-negative chronic hepatitis B

The optimal duration of treatment with nucleos(t)ide analogues (NAs) for patients with HBeAg-negative chronic hepatitis B (CHB) is unknown. The aim of this study was to identify an immune signature associated with off-treatment remission to NA therapy. We performed microarray analysis of peripheral blood mononuclear cell (PBMCs) from six patients with chronic hepatitis B who stopped NA therapy (three with off-treatment remission, three with relapse) and five patients with chronic HBV infection (previously termed 'inactive carriers') served as controls. Results were validated using qRT-PCR on a second group of 21 individuals (17 patients who stopped treatment and four controls). PBMCs from 38 patients on long-term NA treatment were analysed for potential to stop treatment. Microarray analysis indicated that patients with off-treatment remission segregated as a distinct out-group. Twenty-one genes were selected for subsequent validation. Ten of these were expressed at significantly lower levels in the patients with off-treatment remission compared to the patients with relapse and predicted remission with AUC of 0.78-0.92. IFNγ, IL-8, FASLG and CCL4 were the most significant by logistic regression. Twelve (31.6%) of 38 patients on long-term NA therapy had expression levels of all these four genes below cut-off values and hence were candidates for stopping treatment. Our data suggest that patients with HBeAg-negative CHB who remain in off-treatment remission 3 years after NA cessation have a distinct immune signature and that PBMC RNA levels of IFNγ, IL-8, FASLG and CCL4 may serve as potential biomarkers for stopping NA therapy.

NF-κB signaling and crosstalk during carcinogenesis

Transcription factors (TFs) are proteins that control the transcription of genetic information from DNA to mRNA by binding to specific DNA sequences either on their own or with other proteins as a complex. TFs thus support or suppress the recruitment of the corresponding RNA polymerase. In general, TFs are classified by structure or function. The TF, Nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), is expressed in all cell types and tissues. NF-κB signaling and crosstalk are involved in several steps of carcinogenesis including in sequences involving pathogenic stimulus, chronic inflammation, fibrosis, establishment of its remodeling to the precancerous niche (PCN) and transition of a normal cell to a cancer cell. Triggered by various inflammatory cytokines, NF-κB is activated along with other TFs with subsequent stimulation of cell proliferation and inhibition of apoptosis. The involvement of NF-κB in carcinogenesis provides an opportunity to develop anti-NF-κB therapies. The complexity of these interactions requires that we elucidate those aspects of NF-κB interactions that play a role in carcinogenesis, the sequence of events leading to cancer.

Endoplasmic reticulum-mediated induction of interleukin-8 occurs by hepatitis B virus infection and contributes to suppression of interferon responsiveness in human hepatocytes

The events in the immune response to hepatitis B virus (HBV) remain unclear. We analyzed the direct influence of HBV on gene expression in human hepatocytes under immunodeficient conditions using a human hepatocyte chimeric mouse model. HBV-infected or non-infected chimeric mouse livers were collected, and gene expression profiles were compared. Since IL-8 was the most significantly up-regulated gene at 8 weeks after HBV infection, we focused on IL-8 and found that HBx and the large HBs (L-HBs) protein induce transcription of IL-8 via endoplasmic reticulum stress. This stress induces IL-8 transcription via NFAT activation and contributes to suppression of interferon responsiveness in HBV-infected human hepatocytes. In the present study, we identified a novel regulatory mechanism in which the L-HBs protein activates IL-8 via endoplasmic reticulum stress, suggesting a key role for IL-8 in the immune response to HBV and a potential new target for antiviral treatments of HBV infection.

Identification of TRIM14 as a Type I IFN-Stimulated Gene Controlling Hepatitis B Virus Replication by Targeting HBx

Hepatitis B virus (HBV) remains a major cause of hepatic disease that threatens human health worldwide. Type I IFN (IFN-I) therapy is an important therapeutic option for HBV patients. The antiviral effect of IFN is mainly mediated via upregulation of the expressions of the downstream IFN-stimulated genes. However, the mechanisms by which IFN induces ISG production and inhibits HBV replication are yet to be clarified. TRIM14 was recently reported as a key molecule in the IFN-signaling pathway that regulates IFN production in response to viral infection. In this study, we sought to understand the mechanisms by which IFN restricts HBV replication. We confirmed that TRIM14 is an ISG in the hepatic cells, and that the pattern-recognition receptor ligands polyI:C and polydAdT induce TRIM14 dependent on IFN-I production. In addition, IFN-I-activated STAT1 (but not STAT3) directly bound to the TRIM14 promoter and mediated the induction of TRIM14. Interestingly, TRIM14 played an important role in IFN-I-mediated inhibition of HBV, and the TRIM14 SPRY domain interacted with the C-terminal of HBx, which might block the role of HBx in facilitating HBV replication by inhibiting the formation of the Smc-HBx–DDB1 complex. Thus, our study clearly demonstrates that TRIM14 is a STAT1-dependent ISG, and that the IFN-I–TRIM14–HBx axis shows an alternative way to understand the mechanism by which IFN-I inhibits virus replication.

When Hepatitis B Virus Meets Interferons

Chronic hepatitis B virus (HBV) infection imposes a severe burden on global public health. Currently, there are no curative therapies for millions of chronic HBV-infected patients (Lok et al., 2017). Interferon (IFN; including pegylated IFN) is an approved anti-HBV drug that not only exerts direct antiviral activity, but also augments immunity against HBV infection. Through a systematic review of the literature, here we summarize and present recent progress in research regarding the interactions between IFN and HBV as well as dissect the antiviral mechanisms of IFN. We focus on inhibition of HBV replication by IFN-stimulated genes (ISGs) as well as inhibition of IFN signaling by HBV and viral proteins. Finally, we briefly discuss current IFN-based HBV treatment strategies. This review may help to better understand the mechanisms involved in the therapeutic action of IFN as well as the crosstalk between IFN and HBV, and facilitate the development of both direct-acting and immunology-based new HBV drugs.

Type III interferon-induced CBFβ inhibits HBV replication by hijacking HBx

Hepatitis B virus (HBV) and its associated chronic infection remain serious health threats worldwide. However, there is still no impactful approach for clinical treatment of hepatitis B patients. Therefore, developing a better understanding of the interactions between HBV and its host is particularly important. HBV infection has been reported to induce type-III but not type-I or type-II interferon (IFN). In this study, we identified CBFβ, an HIV enhancer, as an HBV restriction factor that is specifically induced by type-III IFN in the early stages of HBV infection. Type-III IFN-induced IL-10 played an important role in the production of CBFβ. Interestingly, the interaction between CBFβ- and HBV-encoded regulatory protein X (HBx) enhanced the stability of CBFβ, but notably blocked HBx-mediated promotion of HBV replication. CBFβ expression was lower in HBV patients than in healthy persons, and the addition of serum from HBV patients inhibited CBFβ expression in HepG2 cells. On the contrary, HBV via HBsAg inhibited type-III IFN-induced CBFβ expression and decreased the anti-HBV activity of type-III IFN, suggesting that HBV inhibits antiviral interferon-stimulated gene (ISG) expression and induces IFN resistance. Collectively, our results demonstrate that type-III IFN-triggered and IL-10-induced CBFβ are crucial factors for inhibiting HBV replication, and the HBx–CBFβ–HBsAg axis reveals a new molecular mechanism of interaction between HBV and its hosts.

3D microfluidic liver cultures as a physiological preclinical tool for hepatitis B virus infection

With more than 240 million people infected, hepatitis B virus (HBV) is a major health concern. The inability to mimic the complexity of the liver using cell lines and regular primary human hepatocyte (PHH) cultures pose significant limitations for studying host/pathogen interactions. Here, we describe a 3D microfluidic PHH system permissive to HBV infection, which can be maintained for at least 40 days. This system enables the recapitulation of all steps of the HBV life cycle, including the replication of patient-derived HBV and the maintenance of HBV cccDNA. We show that innate immune and cytokine responses following infection with HBV mimic those observed in HBV-infected patients, thus allowing the dissection of pathways important for immune evasion and validation of biomarkers. Additionally, we demonstrate that the co-culture of PHH with other non-parenchymal cells enables the identification of the cellular origin of immune effectors, thus providing a valuable preclinical platform for HBV research.

Dysregulated Chemokine Signaling in Cystic Fibrosis Lung Disease: A Potential Therapeutic Target

CF lung disease is characterized by a chronic and non-resolving activation of the innate immune system with excessive release of chemokines/cytokines including IL-8 and persistent infiltration of immune cells, mainly neutrophils, into the airways. Chronic infection and impaired immune response eventually lead to pulmonary damage characterized by bronchiectasis, emphysema, and lung fibrosis. As a complete knowledge of the pathways responsible for the exaggerated inflammatory response in CF lung disease is lacking, understanding these pathways could reveal new therapeutic targets, and lead to novel treatments. Therefore, there is a strong rationale for the identification of mechanisms and pathways underlying the exaggerated inflammatory response in CF lung disease. This article reviews the role of inflammation in the pathogenesis of CF lung disease, with a focus on the dysregulated signaling involved in the overexpression of chemokine IL-8 and excessive recruitment of neutrophils in CF airways. The findings suggest that targeting the exaggerated IL-8/IL-8 receptor (mainly CXCR2) signaling pathway in immune cells (especially neutrophils) may represent a potential therapeutic strategy for CF lung disease.

HDM2 Promotes NEDDylation of Hepatitis B Virus HBx To Enhance Its Stability and Function

Hepatitis B virus (HBV)-encoded X protein (HBx) plays a critical role in HBV-related hepatocarcinoma development. In this study, we demonstrate that HBx is specifically modified by NEDD8. We found that E3 ligase HDM2 promotes NEDDylation of HBx to enhance HBx stability by preventing its ubiquitination-mediated degradation. Consistently, analysis of 160 hepatocellular carcinoma patient specimens indicated that the amount of HDM2 protein correlates with HBx protein level. We identified that HBx K91 and K95 as the key HBx NEDDylation sites and observed that the NEDDylation-deficient HBx has shorter half-life. We generated Huh7 cell lines which ectopically express wild-type and NEDDylation-deficient HBx and found that NEDDylation-deficient HBx showed less chromatin localization and less DDB1 binding. Consistently, the expression of HBx-regulated genes (IL-8, MMP9, and YAP) and HBV transcription (the activity of HBV enhancer and the amount of pgRNA transcribed from cccDNA) were significantly higher in cells expressing wild-type (WT) HBx than that in cells expressing mutant HBx. In addition, HBx-expressing cells proliferated faster than control and mutant HBx-expressing cells. We also showed that the ability of WT HBx-expressing cells to form tumors in nude mice was significantly higher than that of mutant HBx-expressing cells. In conclusion, we revealed that E3 ligase HDM2 promotes NEDDylation of HBx to enhance HBx stability and chromatin localization, which in turn favors HBx-dependent transcriptional regulation, cell proliferation, and HBV-driven tumor growth.IMPORTANCE Hepatitis B virus (HBV) HBx protein plays a critical role in viral replication and hepatocarcinogenesis. However, the regulation of HBx stability is not well understood. We found that HBx is modified by NEDD8 and that the HDM2 E3 ligase promotes HBx NEDDylation to enhance HBx stability by inhibiting its ubiquitination. We provide a new evidence to show the positive correlation between HDM2 and HBx in clinical hepatocellular carcinoma (HCC) samples. We also identified the major NEDDylation sites on HBx. Our studies indicate that the defective NEDDylation of HBx negatively affects its ability to activate the transcription of downstream genes and promote cell proliferation and tumor growth in vivo Taken together, our findings reveal a novel posttranslational modification of HBx by HDM2 which regulates its stability, subcellular localization, and functions. These findings indicate that HDM2 is an important regulator on HBx and a potential diagnosis/therapeutic marker for HBV-associated HCC.

Interferon induces interleukin 8 and bone marrow stromal cell antigen 2 expression, inhibiting the production of hepatitis B virus surface antigen from human hepatocytes

Hepatitis B virus (HBV) surface antigen (HBsAg) loss is one of the treatment goals of chronic HBV infection. Bone marrow stromal cell antigen 2 (BST2) is one of the interferon (IFN)-stimulated genes (ISGs) and inhibits the release of various enveloped viruses. Here we examined the effects of antiviral treatment on HBsAg levels and its intracellular mechanism in HBsAg-producing hepatocytes. In PLC/PRF/5 and Huh1, IFNα-2a treatment decreased HBsAg levels in their conditioned media. Upregulation of interleukin 8 (IL8), toll-like receptor 2 (TLR2) and interferon gamma-induced protein 10 (IP10) mRNAs was associated with the reduction of HBsAg in both PLC/PRF/5 and Huh1. The HBsAg level was upregulated by knockdown of IL8, TLR2 or IP10. Exogenous addition of IL8 enhanced BST2 promoter activity and BST2 mRNA expression. Additionally, knockdown of IL8 could lead to the downregulation of BST2 mRNA. Transfection of poly(I-C) enhanced IL8 and BST2 mRNA expression and inhibited HBsAg secretion from PLC/PRF/5 cells. In conclusion, IL8 might play an important role in the enhancement of BST2 and be involved in HBsAg eradication.

Impact of genetic variations in C-C chemokine receptors and ligands on infectious diseases

Chemokine receptors and ligands are crucial for extensive immune response against infectious diseases such as malaria, leishmaniasis, HIV and tuberculosis and a wide variety of other diseases. Role of chemokines are evidenced in the activation and regulation of immune cell migration which is important for immune response against diseases. Outcome of disease is determined by complex interaction among pathogen, host genetic variability and surrounding milieu. Variation in expression or function of chemokines caused by genetic polymorphisms could be associated with attenuated immune responses. Exploration of chemokine genetic polymorphisms in therapeutic response, gene regulation and disease outcome is important. Infectious agents in human host alter the expression of chemokines via epigenetic alterations and thus contribute to disease pathogenesis. Although some fragmentary data are available on chemokine genetic variations and their contribution in diseases, no unequivocal conclusion has been arrived as yet. We therefore, aim to investigate the association of CCR5-CCL5 and CCR2-CCL2 genetic polymorphisms with different infectious diseases, transcriptional regulation of gene, disease severity and response to therapy. Furthermore, the role of epigenetics in genes related to chemokines and infectious disease are also discussed.

Chemokine Expression Profiles of Human Hepatoma Cell Lines Mediated by Hepatitis B Virus X Protein

The hepatitis B virus X protein (HBx), which is encoded by hepatitis B virus (HBV), plays crucial roles in the tumorigenesis of HBV associated hepatocellular carcinoma (HCC). Recent studies suggest that the HBx is involved in regulation of host immune cytokines and chemokines in HBV-associated HCC patients. However, effects of the HBx on autocrine chemokine expression profiles of hepatoma cells, which were shown in modulation of tumor-immune cell interactions, have not been investigated comprehensively. In the present study, human hepatoma cell lines SMMC-7721 and HepG2 were transfected with HBx-expressing plasmid. Human chemokine antibody array 1 (RayBio®), which simultaneously detects 38 chemokine factors, was used to determine chemokine expression profiles. Real-time polymerase chain reaction (real-time PCR) was used to further confirm the differential expression of chemokines. Chemokine antibody array revealed that all 38 chomekines were found to be expressed by SMMC-7721 and HepG2 cell lines. Interleukin-8 (IL-8) was obviously up-regulated, and epithelial neutrophil-activating protein 78 (ENA78), eosinophil chemotactic protein-1 (Eotaxin-1), monocyte chemotactic protein-1 (MCP-1), MCP-2, MCP-3 and macrophage inflammatory protein-3β (MIP-3β) were significantly declined in both cell lines following transfection of HBx-expressing plasmid. Other chemokines showed little or no significant changes. HBx-induced differential chemokine expression levels were validated by real-time PCR. Hierarchical cluster analysis identified a distinction of chomekine expression profiles between HBX-expressing hepatoma cell lines and controls. Our findings provide new evidence that HBx is able to selectively regulate chomekines in hepatoma cells that may be involved in the regulation of tumor-immune cell interactions.

Autophagy Mediates HBx-Induced Nuclear Factor-κB Activation and Release of IL-6, IL-8, and CXCL2 in Hepatocytes

Hepatitis B virus (HBV) and one of its encoded proteins, HBV X protein (HBx), have been shown to induce autophagy in hepatoma cells. Substantial evidence indicates that autophagy is a potent suppressor of inflammation. However, sporadic reports suggest that autophagy could promote pro-inflammatory cytokine expression and inflammation in some biological contexts. Here, we show that overexpression of HBx induces LC3B-positive autophagosome formation, increases autophagic flux and enhances the expression of ATG5, ATG7, and LC3B-II in normal hepatocytes. Abrogation of autophagy by small interfering RNA against ATG5 and ATG7 prevents HBx-induced formation of autophagosomes. Autophagy inhibition also abrogates HBx-induced activation of nuclear factor-κB (NF-κB) and production of interleukin-6 (IL-6), IL-8, and CXCL2. These findings suggest that autophagy is required for HBx-induced NF-κB activation and pro-inflammatory cytokine production and could shed new light on the complex role of autophagy in the modulation of inflammation.

HCV NS5A Up-Regulates COX-2 Expression via IL-8-Mediated Activation of the ERK/JNK MAPK Pathway

Chronic hepatitis C virus (HCV) infection leads to intrahepatic inflammation and liver cell injury, which are considered a risk factor for virus-associated hepatitis, cirrhosis, and hepatocellular carcinoma worldwide. Inflammatory cytokines are critical components of the immune system and influence cellular signaling, and genetic imbalances. In this study, we found that cyclooxygenase-2 (COX-2) and interleukin-8 (IL-8) were significantly induced by HCV infection and HCV NS5A expression, and induction of COX-2 correlated with HCV-induced IL-8 production. We also found that the ERK and JNK signaling pathways were involved in the regulation of IL-8-mediated COX-2 induction in response to HCV infection. Using a promoter-linked reporter assay, we identified that the C/EBP regulatory element within the COX-2 promoter was the dominant factor responsible for the induction of COX-2 by HCV. Silencing C/EBP attenuated HCV-induced COX-2 expression. Our results revealed that HCV-induced inflammation promotes viral replication, providing new insights into the involvement of IL-8-mediated COX-2 induction in HCV replication.

miR-106a Is Downregulated in Peripheral Blood Mononuclear Cells of Chronic Hepatitis B and Associated with Enhanced Levels of Interleukin-8

Aims. This study aimed to investigate miR-106a expression in peripheral blood mononuclear cells (PBMCs) of chronic hepatitis B (CHB) patients and to analyze the function of miR-106a. Materials and Methods. miR-106a expression levels in PBMCs from 40 healthy controls and 56 CHB patients were analyzed by quantitative real-time polymerase chain reaction (qRT-PCR). The luciferase activity assays were used to determine whether miR-106a binds to 3′UTR of IL-8. miR-106a mimics and inhibitors were transfected into healthy PBMCs. IL-8 mRNA and protein levels were detected and determined by qRT-PCR and ELISA, respectively. Results. The qRT-PCR results suggested that the PBMC miR-106a levels were decreased in CHB patients. IL-8 was augmented in CHB patients and was inversely correlated with miR-106a levels. The luciferase activity assays indicated that IL-8 is a target of miR-106a. Exogenous expression of miR-106a could significantly repress IL-8 expression at both mRNA and protein levels in PBMCs, whereas miR-106a inhibitor had the opposite effects. Conclusions. This study suggested that miR-106a is downregulated in PBMCs of CHB patients and that miR-106a may play an important role in CHB by targeting IL-8.

Effects of Bush Sophora Root polysaccharide and its sulfate on immuno-enhancing of the therapeutic DVH

Bush Sophora Root polysaccharide (BSRPS) and its sulfate, sulfated Bush Sophora Root polysaccharide (sBSRPS), possess the antiviral activities against duck hepatitis A virus. However their antiviral mechanisms are still not clear. This paper reported their immuno-enhancing roles in the therapeutic effects for duck virus hepatitis (DVH). The effects of BSRPS and sBSRPS on stimulating lymphocyte proliferation were investigated by MTT methods. After that, ducklings were challenged with DHAV and treated with BSRPS and sBSRPS. Meanwhile, the total antibody (Ab), cytokines including interferon gamma (IFN-γ), hepatocyte growth factor (HGF), interleukin (IL)-2, IL-6 and IL-8 were determined by enzyme-linked immuno sorbent assay methods. The results showed that BSRPS owned a fine hepatoprotective effect with stable HGF producing ability. Sulfated modification was able to increase the proliferation rates of B and T lymphocytes and the secretions of total Ab, IFN-γ and IL-2, as comparison with those of BSRPS group. In summary, both of them exhibited immuno-enhancing effects on the therapeutic effects for DVH, and the capacity of sBSRPS was stronger than that of BSRPS.

Current and future antiviral drug therapies of hepatitis B chronic infection

Despite significant improvement in the management of chronic hepatitis B virus (HBV) it remains a public health problem, affecting more than 350 million people worldwide. The natural course of the infection is dynamic and involves a complex interplay between the virus and the host’s immune system. Currently the approved therapeutic regimens include pegylated-interferon (IFN)-α and monotherapy with five nucleos(t)ide analogues (NAs). Both antiviral treatments are not capable to eliminate the virus and do not establish long-term control of infection after treatment withdrawal. IFN therapy is of finite duration and associates with low response rates, liver decompensating and numerous side effects. NAs are well-tolerated therapies but have a high risk of drug resistance development that limits their prolonged use. The imperative for the development of new approaches for the treatment of chronic HBV infection is a challenging issue that cannot be over-sided. Research efforts are focusing on the identification and evaluation of various viral replication inhibitors that target viral replication and a number of immunomodulators that aim to restore the HBV specific immune hyporesponsiveness without inducing liver damage. This review brings together our current knowledge on the available treatment and discusses potential therapeutic approaches in the battle against chronic HBV infection.

Paeoniflorin diminishes ConA-induced IL-8 production in primary human hepatic sinusoidal endothelial cells in the involvement of ERK1/2 and Akt phosphorylation

Liver diseases are closely associated with elevated levels of interleukin-8 (IL-8), suggesting the ability to inhibit IL-8 production could enhance the treatment of liver diseases. Paeoniflorin is a major active constituent of dried Paeoniae Radix Alba root (Baishao in Chinese) which is widely used in China to treat liver diseases. We examined the effects and underlying mechanisms of paeoniflorin on IL-8 production in primary human hepatic sinusoidal endothelial cells (HHSECs). Concanavalin A (ConA) at 20 μg/mL produced a 5.2-fold increase in IL-8 mRNA by 8h, and a 14.2-fold rise in IL-8 levels by 16 h. Inhibition of MEK (ERK kinase) and extracellular signal-regulated kinase (ERK) by PD98059 and U0126, or inhibition of phosphatidylinositol 3-kinase (PI3K) by LY294002 blocked both ConA-induced IL-8 mRNA expression and IL-8 secretion. Paeoniflorin reduced ConA-induced IL-8 mRNA expression and IL-8 release by 57.9% and 52.8%, respectively, and also decreased ConA-stimulated phosphorylation of ERK1/2 and Akt, suggesting paeoniflorin inhibits IL-8 expression and release by inhibiting the ERK1/2 and Akt pathways. Combining paeoniflorin with U0126 or LY294002 at low doses showed supra-additive inhibition of not only phospho-ERK1/2 and phospho-Akt by 46.4% and 35.0%, but also IL-8 release by 42.4% and 36.1% and IL-8 mRNA expression by 43.5% and 31.8%, respectively. In conclusion, paeoniflorin most likely contributes to the therapy for liver disease by exerting anti-inflammatory effects on HHSECs through blocking IL-8 secretion via downregulation of ERK1/2 and Akt phosphorylation.

Efficacy of telbivudine in the treatment of chronic hepatitis b and liver cirrhosis and its effect on immunological responses

This study was aimed to evaluate the long-term effects of telbivudine (LdT) in the treatment of chronic hepatitis B (CHB) and HBV-related liver cirrhosis (LC) and to observe the changes of immunological responses during LdT treatment. Clinical data of 80 CHB and 28 HBV-related LC patients who were administered with LdT for 108 weeks and followed up were retrospectively analyzed. The liver function indicators including ALT, AST and γ-GT, HBV DNA copy number in serum and the rates of hepatitis B e antigen (HBeAg) seroconversion were analyzed before and 12, 24, 36, 48, 60, 72, 84, 96 and 108 weeks after LdT treatment in CHB and LC groups. Four serum fibrosis-related markers, including hyaluronic acid (HA), human laminin (LN), human type IV collagen (IV-C) and human N-terminal procollagen III peptide (PC-III), were detected before and after LdT treatment in LC group. The results showed favorable viral suppression and biochemical responses after treatment with LdT for 12 weeks, and a high rate of virological and biochemical control was maintained during the course of 108-week treatment in both CHB and LC groups. The four fibrosis-related markers, especially HA and LN, were down-regulated to some degrees in LC group. Moreover, LdT treatment led to the fluctuation of the circulating interferon-γ (IFN-γ) and interleukin-10 (IL-10) levels at different time points in CHB group. It was concluded that LdT could favorably lead to the virological suppression and biochemical remission. Besides, IFN-γ and IL-10 may represent a suitable and effective predictor of responsiveness during LdT therapy.

Targeting the Achilles heel of the hepatitis B virus: a review of current treatments against covalently closed circular DNA

Chronic infection with hepatitis B virus (HBV) often leads to the development of liver cancer and cirrhosis, creating immense sociological, clinical and economic burdens worldwide. Although current anti-HBV medications manage to control the disease progression and help restore normal liver functions, they often fail to eliminate the virus completely. A major reason for this failure is the presence of a stable viral genome in the hepatocyte nucleus: the covalently closed circular DNA (cccDNA). Targeting HBV cccDNA is a promising approach that could lead to a complete cure. Here, we review various research approaches that are directed toward eliminating HBV cccDNA. This is a brief, yet comprehensive, summary of current state-of-the-art developments in this emerging area of interest.

Viral (hepatitis C virus, hepatitis B virus, HIV) persistence and immune homeostasis

Immune homeostasis is a host characteristic that maintains biological balance within a host. Humans have evolved many host defence mechanisms that ensure the survival of individuals upon encountering a pathogenic infection, with recovery or persistence from a viral infection being determined by both viral factors and host immunity. Chronic viral infections, such as hepatitis B virus, hepatitis C virus and HIV, often result in chronic fluctuating viraemia in the face of host cellular and humoral immune responses, which are dysregulated by multi-faceted mechanisms that are incompletely understood. This review attempts to illuminate the mechanisms involved in this process, focusing on immune homeostasis in the setting of persistent viral infection from the aspects of host defence mechanism, including interferon-stimulated genes, apolipoprotein B mRNA editing enzyme catalytic polypeptide 3 (APOBEC3), autophagy and interactions of various immune cells, cytokines and regulatory molecules.

Enhanced levels of interleukin-8 are associated with hepatitis B virus infection and resistance to interferon-alpha therapy

The objective of this study was to analyze the expression levels of IL-8 in serum and liver tissues from patients with chronic hepatitis B (CHB) infection and to investigate whether IL-8 may antagonize interferon-alpha (IFN-α) antiviral activity against HBV. IL-8 expression in serum was determined by enzyme linked immunosorbent assay (ELISA), and fluorescence-based quantitative real-time PCR (RT-qPCR) was used to measure IL-8 mRNA in peripheral blood mononuclear cells (PBMCs) in patients with CHB. IL-8 protein expression was detected in liver biopsy tissues by immunohistochemistry. In addition, the differences in serum IL-8 and PBMCs mRNA levels were also observed in patients with different anti-viral responses to IFN-α. Compared to normal controls, serum IL-8 protein and mRNA levels were increased in CHB patients, IL-8 levels were positively correlated with the severity of liver inflammation/fibrosis. Moreover, serum IL-8 protein and mRNA levels were positively correlated with serum alanine aminotransferase (ALT) level and negatively correlated with serum prealbumin (PA) level. IL-8 expression was mainly located in portal area of liver tissues and was increased with the severity of liver inflammation and fibrosis stage. The expression serum and mRNA levels of IL-8 in the CHB patients with a complete response to IFN-α are significantly lower than that of the patients with non-response to IFN-α treatment. It is suggested that IL-8 might play important roles in the pathogenesis of CHB. Moreover, interferon resistance may be related to the up-regulation of IL-8 expression in the patients did not respond to IFN-α treatment.

MiRNA-181a regulates Toll-like receptor agonist-induced inflammatory response in human fibroblasts

MicroRNAs (miRNA) regulate the synthesis of cytokines in response to Toll-like receptor (TLR) activation. Our recent microarray study comparing normal and inflamed human dental pulps showed that miRNA-181 (miR-181) family is differentially expressed in the presence of inflammation. Prior studies have reported that the dental pulp, which is composed primarily of TLR4/2+ fibroblasts, expresses elevated levels of cytokines including Interleukin-8 (IL-8) when inflamed. In this study, we employed an in-vitro model to determine the role of the miRNA 181 family in the TLR agonist-induced response in human fibroblasts. TLR4/2+ primary human dental pulp fibroblasts were stimulated with lipopolysaccharide from Porphyromonas gingivalis (Pg LPS), a known oral pathogen, and IL-8 and miR-181 expression measured. An inversely proportional relationship between IL-8 and miR-181a was observed. In-silico analysis identified a miR-181a binding site on the 3′UTR of IL-8 which was confirmed by dual-luciferase assays. MiR-181a directly binds to the 3′UTR of IL-8, an important inflammatory component of the immune response, and modulates its levels. This is the very first report demonstrating miR-181a regulation of IL-8.

The roles of hepatitis B virus-encoded X protein in virus replication and the pathogenesis of chronic liver disease

INTRODUCTION

Hepatitis B virus (HBV) is a major cause of chronic liver disease (CLD) and hepatocellular carcinoma (HCC) worldwide. More than 350 million people are at risk for HCC, and with few treatment options available, therapeutic approaches to targets other than the virus polymerase will be needed. This review suggests that the HBV-encoded X protein, HBx, would be an outstanding target because it contributes to the biology and pathogenesis of HBV in three fundamental ways.

AREAS COVERED

First, HBx is a trans-activating protein that stimulates virus gene expression and replication, thereby promoting the development and persistence of the carrier state. Second, HBx partially blocks the development of immune responses that would otherwise clear the virus, and protects infected hepatocytes from immune-mediated destruction. Thus, HBx contributes to the development of CLD without virus clearance. Third, HBx alters patterns of host gene expression that make possible the emergence of HCC. The selected literature cited is from the National Library of Medicine (Pubmed and Medline).

EXPERT OPINION

Understanding the mechanisms, whereby HBx supports virus replication and promotes pathogenesis, suggests that HBx will be an important therapeutic target against both virus replication and CLD aimed at the chemoprevention of HCC.