Veritable antiviral capacity of natural killer cells in chronic HBV infection: an argument for an earlier anti-virus treatment

Impact of lamivudine treatment in late pregnancy on the development of the foetal immune response to hepatitis B virus: a meta-analysis in R with the metafor package

BACKGROUND

Hepatitis B virus (HBV) infection is a worldwide public health burden, especially in Asia and Africa. Concerns were raised that foetal exposure to HBV and antiretroviral therapy (ART) might suppress the innate immune response and reduce the production of hepatitis B surface antibody (HBsAb) in foetuses and infants. We therefore conducted the current study to evaluate the impact of ART on the development of the immune response to HBV in foetuses and infants.

METHODS

We selected lamivudine instead of telbivudine or tenofovir as the intervention measurement because it was the oldest and most widely used ART during pregnancy and its safety data have been sufficiently documented. A comprehensive search was conducted in eight electronic databases, including four Chinese and four English databases. Studies that met the following eligibility criteria were included: human randomized controlled trials (RCTs); participants in the treatment group were exclusively exposed to lamivudine; participants in the control group were exposed to placebo, no treatment or hepatitis B immunoglobulin; all participants were HBV-positive pregnant women with a high viral load and the main outcome of interest was neonatal HBsAb seropositivity. Data were tabulated and analysed using R software.

RESULTS

Nine RCTs were included and analysed. Compared with controls, lamivudine significantly decreased HBsAb seronegativity in the newborn within 24 h after birth (indicating the foetal immune response to HBV). Similar results were noted in infants within 6-7 months after birth and infants within 12 months (indicating the neonatal immune response to HBV vaccine).

CONCLUSIONS

Lamivudine treatment in late pregnancy boosted the foetal immune response to HBV in utero and enhanced the neonatal immune response to hepatitis B vaccine after birth.

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

Objective

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

Methods

In this prospective research, HBeAg-positive patients with CHB received PEG-IFN α-2a treatment, completing 4-year follow-up. After PEG-IFN α-2a treatment, undetectable HBV DNA, HBsAg loss, and HBeAg disappearance were defined as functional cure. Proportions of NK, CD56^dim, CD56^bright, NKp46⁺, NKp46^dim, NKp46^high, and interferon alpha receptor 2 (IFNAR2)⁺ NK cells, and the mean fluorescence intensity (MFI) of NK cell surface receptors IFNAR2 and NKp46 were detected.

Results

66 patients were enrolled into the study in which 17 patients obtained functional cure. At baseline, hepatitis B virus desoxyribose nucleic acid (HBV DNA) titer in patients with functional cure was remarkably lower than that in Non-functional cure group. Compared with baseline, HBV DNA levels, HBsAg levels, and HBeAg levels significantly declined at week 12 and 24 of therapy in patients with functional cure. At baseline, the negative correlation between CD56^bright NK% and HBV DNA and the negative correlation between CD56^dim NK% and HBV DNA was showed; CD56^bright NK% and IFNAR2 MFI in patients with functional cure were remarkably higher than those in patients without functional cure. After therapy, CD56^bright NK% and NKp46^high NK% in patients with functional cure were higher than those in patients without functional cure. In Functional cure group, after 24 weeks of treatment NK%, CD56^bright NK%, IFNAR2 MFI weakly increased, and NKp46^high NK% and NKp46 MFI significantly increased, meanwhile, CD56^dim NK% and NKp46^dim NK% decreased. Only NKp46 MFI increased after therapy in patients without functional cure.

Conclusion

The lower HBV DNA load and the higher CD56^bright NK% before therapy, and the higher the post-treatment CD56^bright NK%, IFNAR2 MFI, NKp46^high NK%, the easier to achieve functional cure.

Association of Serum 25(OH)D Deficiency with High Viral Load in HBV Infected Patients

Hepatitis B virus (HBV) is a significant public health concern, particularly in low-income countries. The host immune response plays an essential role in hepatitis B virus outcome, mainly orchestrated by cytokines and immune modulators molecules such as vitamin D. This study aimed to determine the levels of cytokines (IL-10), interferon-gamma (IFN-gamma), interferon-lambada (IFN-lambada), granzyme B, and vitamin D in Khartoum, Sudan, and to assess the association between them and variable HBV viral load as well as liver enzyme levels. A total of 174 participants were enrolled in the trial, with 100 HBV-infected patients (who were HIV and HCV negative) and 74 healthy volunteers. Patients’ HBV viral load, vitamin D levels, liver enzymes, and circulatory cytokines were measured. This study revealed a remarkable decrease in vitamin D levels in HBV infected patients with an elevation in levels of liver biomarkers. The level of IL-10 was significantly higher in patients than in apparently healthy controls (p-value <0.001). There was a positive correlation between IFN-ϒ, Granzyme B, and viral load. According to the findings of this study, there is a marked hypovitaminosis D among hepatitis B infected patients with a significant increase in IL-10, which may implicate the persistence of HBV infection. Moreover, HBV DNA levels were significantly associated with IFN- g and granzyme B levels.

Clinical treatment of chronic hepatitis B virus infection in indeterminate phase: Current status and future prospects

The natural history of chronic hepatitis B virus (HBV) infection is usually divided into four stages: Immune tolerant phase (IT), hepatitis B e antigen (HBeAg) positive chronic hepatitis B (CHB) (i.e., immune clearance phase), immune control (IC) phase, and HBeAg negative CHB (i.e., reactivation phase). Patients whose HBeAg, alanine aminotransferase (ALT), HBV DNA, and hepatic histopathology fall into an indeterminate phase are divided into the following four groups: (1) Indeterminate phase related to IT: HBV DNA < 10⁶ IU/mL or significant inflammation and fibrosis, while other indicators are in line with IT; (2) Indeterminate phase related to HBeAg positive CHB: HBV DNA < 2 × 10⁴ IU/mL or ALT 1-2 times the upper limit of normal (ULN), while the rest indicators are consistent with HBeAg positive CHB; (3) Indeterminate phase related to IC: HBV DNA > 2 × 10³ IU/mL or significant inflammation and fibrosis, while other indicators meet IC; and (4) Indeterminate phase related to HBeAg negative CHB: HBV DNA < 2 × 10³ IU/mL or ALT 1-2 ULN, while the remaining indicators are in accordance with HBeAg negative CHB. In China, it is estimated that about 70 million people have chronic HBV infection, of which about 20-30 million are CHB patients. The percentage of liver cirrhosis and hepatocellular carcinoma caused by HBV infection is 77% and 84%, respectively. Chronic HBV infection brings severe burden to people's life and health as well as the national health care system. Although existing guidelines recommend dynamic monitoring of serum ALT and HBV DNA levels and assessment of liver histology of indeterminate zone, whether to initiate antiviral therapy in these patients remains controversial. This review mainly introduces the clinical treatment status of CHB patients in IC and indeterminate phase related to IC, and the future prospects of antiviral treatment for these patients.

Expression and clinical significance of inhibitory receptor Leukocyte-associated immunoglobulin-like receptor-1 on peripheral blood T cells of chronic hepatitis B patients: A cross-sectional study

Leukocyte-associated immunoglobulin-like receptor-1 (LAIR-1) is an inhibitory receptor that is expressed on the surface of multiple immune cells and plays key roles in immune modulation. In patients with chronic hepatitis B (CHB), T cell number and functions are abnormal and the expression of inhibitory receptors is elevated. However, the expression of LAIR-1 on T cells in patients with CHB is still undetermined.We recruited 320 patients with CHB in different disease phases and 17 healthy donors. Serum biochemical and virological examinations were performed for each participant, and their demographic and clinical data were collected. According to the latest American Association for the Study of Liver Disease guidelines, we categorized the patients into 4 groups: immune active, immune tolerant, inactive CHB, and gray zone. Additionally, we tested the expression of LAIR-1 on T cells and T cell subsets using flow cytometry.We observed a significant decrease in LAIR-1 expression on CD3+ T cells and its two subsets (CD4+ and CD8+ T cells) in patients with CHB. LAIR-1 expression on T cells was the lowest in the immune active group. LAIR-1 expression levels on CD4+ and CD8+ T cells showed a significant negative association with hepatitis B virus (HBV) DNA load and were lower in hepatitis B e antigen (HBeAg)-positive patients than in HBeAg-negative patients (P < .05). In addition, LAIR-1 expression levels on CD3+, CD4+, and CD8+ T cells were all negatively associated with liver inflammation and fibrosis parameters, such as alanine aminotransferase and aspartate aminotransferase levels, FibroScan value, and aspartate aminotransferase-to-platelet ratio index score.LAIR-1 expression levels on T cells were associated with HBV DNA load and liver inflammation and fibrosis parameters, indicating that LAIR-1 may play an important regulatory role in HBV-induced T cell immune pathogenesis and may be a therapeutic target for CHB.

Serum HBV pregenomic RNA exhibited opposite associations with NKdim and NKbright cell immunity in treatment-naïve chronic hepatitis B patients

Hepatitis B virus (HBV) pregenomic RNA (pgRNA) is a new biomarker that reflects HBV replication, but its relationship with natural killer (NK) cell immunity in chronic hepatitis B (CHB) is unknown. We assessed serum HBV pgRNA levels in 323 CHB patients by reverse transcription-polymerase chain reaction, assessed cytokine production and activation and inhibitory markers of NK cells by flow cytometry, and measured serum cytokines by enzyme-linked immunosorbent assays (ELISAs). Among the different CHB phases, the serum HBV pgRNA level was highest in the immune-tolerant (IT) and immune-active (IA) phases. Regarding NK and NKdim cells, HBV pgRNA was negatively associated with frequencies, but positively associated with NKp44 and NKp46 expression (activation markers). Regarding NKbright cells, serum HBV pgRNA was positively associated with frequency and programmed cell death protein 1 (PD1) expression (inhibitory marker), but negatively associated with NKp44 and NKp46. Serum HBV pgRNA was not associated with NKp30 (activation marker) on NK cells or subsets. Lastly, serum HBV pgRNA was positively correlated with the levels of serum IL-7 and IL-12P40 (NK cell-promoting cytokines) and negatively correlated with serum prostaglandin E2 (PGE2) level (which negatively regulates NK cells). In conclusion, we found varied relationships between serum HBV pgRNA and NK cells and subsets, indicating that HBV pgRNA may play a complicated role in NK cell-related immunity, providing new information on HBV and host immunity.

Variation and expression of HLA-DPB1 gene in HBV infection

Hepatitis B virus (HBV) affects approximately 68 million people in China, and 10-15% of adults infected with HBV develop chronic hepatitis B, liver cirrhosis, liver failure or hepatocellular carcinoma (HCC). HLA-DPB1 gene polymorphism and expression have been shown to be associated with HBV infection susceptibility and spontaneous clearance. The aim of this study is to evaluate the role of HLA-DPB1 gene polymorphism in HBV infection. HLA-DPB1 and rs9277535 polymorphisms were investigated in 259 patients with HBV infection and 442 healthy controls (HCs) using sequence-based typing. The mRNA of HLA-DPB1 was measured by real-time polymerase chain reaction. HLA-DPB1 genes and rs9277535 polymorphisms were all associated with HBV infection in the Sichuan Han population. rs9277535A and HLA-DPB1*04:02 played a protective role against HBV infection. rs9277535G and DPB1*05:01 were associated with susceptibility to HBV infection. rs9277535GG had significantly higher HLA-DPB1 mRNA expression in the HBV infection group compared with the HC group. HLA-DPB1*05:01 and HLA-DPB1*21:01 had significantly lower mRNA expression in the HBV infection group compared with the HC group. The meta-analysis revealed that HLA-DPB1*02:01, HLA-DPB1*02:02, HAL-DPB1*04:01 and HLA-DPB1*04:02 protected against HBV infection, while HLA-DPB1*05:01, HLA-DPB1*09:01, and HLA-DPB1*13:01 were risk factors for susceptibility to HBV infection. HLA-DPB1*02:01, HLA-DPB1*02:02, and HLA-DPB1*04:01 were associated with HBV spontaneous clearance, while HLA-DPB1*05:01 was associated with chronic HBV infection. HLA-DPB1 alleles and rs9277535 have a major effect on the risk of HBV infection, and HBV infection is associated with lower HLA-DPB1 expression. HLA-DPB1 alleles have an important role in HBV susceptibility and spontaneous clearance.

Quantative HBsAg level correlates dendritic cells maturation in chronic hepatitis B patients

BACKGROUND

In order to better understand the role of Dendritic cells (DCs) in Chronic Hepatitis B (CHB), we investigated the frequencies and maturation markers on DCs in CHB patients and its change during entecavir treatment.

METHODS

Twenty-six CHB patients on anti-virus treatment for 48 weeks were included in this study. Patients' blood samples were collected on every 3 months since starting treatment. Samples on baseline and after 48 weeks treatment were examined using flow-cytometry to investigate frequencies and maturation markers of DCs.

RESULTS

The frequencies of myeloid DCs (mDCs) and plasmacytoid DCs (pDCs) were lower in CHB patients than healthy controls on baseline. pDCs frequencies and mDCs maturation markers expression were increased after entecavir (ETV) treatment. Patients with higher baseline HBsAg levels showed a poorer maturation status than those with low baseline HBsAg levels, regardless of changes in HBsAg levels after treatment.

CONCLUSIONS

Entecavir treatment could restore the decreased DCs frequencies in CHB patients and improve DCs maturation levels. Baseline HBsAg level is an important factor that affecting DCs.

Aberrant anti-viral response of natural killer cells in severe asthma

Rhinovirus infections are the main cause of asthma exacerbations. As natural killer (NK) cells are important actors of the antiviral innate response, we aimed at evaluating the functions of NK cells from severe asthma patients in response to rhinovirus-like molecules or rhinoviruses.Peripheral blood mononuclear cells from patients with severe asthma and healthy donors were stimulated with pathogen-like molecules or with the rhinoviruses (RV)-A9 and RV-2. NK cell activation, degranulation and interferon (IFN)-γ expression were analysed.NK cells from severe asthma patients were less cytotoxic than those from healthy donors in response to toll-like receptor (TLR)3, TLR7/8 or RV-A9 but not in response to RV-2 stimulation. Furthermore, when cultured with interleukin (IL)-12+IL-15, cytokines which are produced during viral infections, NK cells from patients with severe asthma were less cytotoxic and expressed less IFN-γ than NK cells from healthy donors. NK cells from severe asthmatics exhibited an exhausted phenotype, with an increased expression of the checkpoint molecule Tim-3.Together, our findings indicate that the activation of NK cells from patients with severe asthma may be insufficient during some but not all respiratory infections. The exhausted phenotype may participate in NK cell impairment and aggravation of viral-induced asthma exacerbation in these patients.

Soluble programmed death-1 is a useful indicator for inflammatory and fibrosis severity in chronic hepatitis B

Elevated programmed death-1 (PD-1) has been found in immune cells in viral infections and plays an important role in infection persistence. The soluble form of PD-1 (sPD-1) is involved in tumours and viral infections. The aim of this study was to investigate the role of sPD-1 in chronic hepatitis B (CHB). A total of two hundred and eighteen CHB patients and sixty healthy controls (HC) were enrolled. Demographic data and clinical parameters were collected. An ELISA assay was used to measure serum sPD-1 levels, and the relationships between sPD-1 and clinical/virological characteristics was analysed. sPD-1 levels in CHB patients were higher (median 4.409 IQR 3.435-5.306 pg/mL) than those of HC individuals (median 0.3665 IQR 0.2425-0.5010 pg/mL). Among patients at various disease stages, patients with immune activity showed the highest sPD-1 levels (median 5.138 IQR 4.329-5.406 pg/mL). sPD-1 concentration was associated with HBV markers (HBsAg, HBV DNA and HBeAg) and biochemical parameters (serum aspartate aminotransferase [AST], alanine aminotransferase [ALT], total bilirubin [TBil] and gamma glutamyl transferase [γ-GT] levels) (all P < 0.05). sPD-1 levels were higher in CHB patients with moderate-to-severe inflammation or fibrosis than in those with mild inflammation or fibrosis, regardless of ALT levels. The association between sPD-1 and disease progression of CHB suggests that sPD-1 could serve as a new indicator in assessing liver fibrosis. These findings may further aid in determining the initiation of antiviral treatment in patients with normal ALT levels.

B7-H6 expression in human hepatocellular carcinoma and its clinical significance [corrected]

Background

Recent studies have suggested that B7-H6, a new member of the B7 family of ligands, not only is a crucial regulator of NK cell-mediated immune responses but also has important clinical implications due to its abnormal expression in many human cancers. We have previously reported that higher B7-H6 expression levels in ovarian cancer tissues are positively correlated with tumor metastasis and cancer progression. To date, the expression of B7-H6 in human hepatocellular carcinoma (HCC) and the clinical significance of B7-H6 expression still remain elusive.

Methods

In the present study, the expression level of B7-H6 was examined in both HCC tissues and HCC cell lines (HepG2 and SMMC-7721). And the clinical significance of B7-H6 was analyzed as well.

Results

Our results revealed that B7-H6 was expressed abnormally in HCC tissues, which was greatly related to tumor size. The TCGA data also showed that the B7-H6 mRNA expression level was significantly negatively correlated with the survival of HCC patients. Next, to investigate the functions of B7-H6 in HCC, we successfully constructed B7-H6 knockdown expression human HCC cell lines using the RNA interference technology. Our studies showed that reduced expression of B7-H6 in HepG2 and SMMC-7721 cells significantly attenuated cell proliferation as well as cell migration and invasion. Besides, depletion of B7-H6 greatly induced cell cycle arrest at G1 phase. And also B7-H6 knockdown in HCC cell lines dramatically decreased the C-myc, C-fos and Cyclin-D1 expression.

Conclusions

Our present findings suggested that B7-H6 played an important role in oncogenesis of HCC on cellular level, and B7-H6 could be employed to develop immunotherapeutic approaches targeting this malignancy.

Why, who and when to start treatment for chronic hepatitis B infection

Chronic hepatitis B remains a major global health challenge due to morbidity and mortality from hepatocellular carcinoma and complications of liver cirrhosis. Current treatment regimens are non-curative and, once initiated, treatment is of indefinite duration for the majority. The decision to initiate treatment decisions is based on risk stratification. Advances in our understanding of the natural history of chronic hepatitis B have led to a paradigm shift in recommendations for treatment. Emerging non-invasive biomarkers of disease activity will further enhance disease stratification. In this review, we summarise the guidance from major international societies on treatment for chronic hepatitis B and explore some of the novel approaches to disease assessment.