Chimeric antigen receptors of HBV envelope proteins inhibit hepatitis B surface antigen secretion.

OBJECTIVES: Chronic hepatitis B (CHB) caused by HBV infection greatly increases the risk of liver cirrhosis and hepatocellular carcinoma. Hepatitis B surface antigen (HBsAg) plays critical roles in the pathogenesis of CHB. HBsAg loss is the key indicator for cure of CHB, but is rarely achieved by current approved anti-HBV drugs. Therefore, novel anti-HBV strategies are urgently needed to achieve sustained HBsAg loss. DESIGN: We developed multiple chimeric antigen receptors (CARs) based on single-chain variable fragments (scFvs, namely MA18/7-scFv and G12-scFv), respectively, targeting HBV large and small envelope proteins. Their impacts on HBsAg secretion and HBV infection, and the underlying mechanisms, were extensively investigated using various cell culture models and HBV mouse models. RESULTS: After secretory signal peptide mediated translocation into endoplasmic reticulum (ER) and secretory pathway, MA18/7-scFv and CARs blocked HBV infection and virion secretion. G12-scFv preferentially inhibited virion secretion, while both its CAR formats and crystallisable fragment (Fc)-attached versions blocked HBsAg secretion. G12-scFv and G12-CAR arrested HBV envelope proteins mainly in ER and potently inhibited HBV budding. Furthermore, G12-scFv-Fc and G12-CAR-Fc strongly suppressed serum HBsAg up to 130-fold in HBV mouse models. The inhibitory effect lasted for at least 8 weeks when delivered by an adeno-associated virus vector. CONCLUSION: CARs possess direct antiviral activity, besides the well-known application in T-cell therapy. Fc attached G12-scFv and G12-CARs could provide a novel approach for reducing circulating HBsAg.

Spatial transcriptomics reveals a low extent of transcriptionally active hepatitis B virus integration in patients with HBsAg loss.

OBJECTIVE: Hepatitis B virus (HBV) can integrate into the chromosomes of infected hepatocytes, contributing to the production of hepatitis B surface antigen (HBsAg) and to hepatocarcinogenesis. In this study, we aimed to explore whether transcriptionally active HBV integration events spread throughout the liver tissue in different phases of chronic HBV infection, especially in patients with HBsAg loss. DESIGN: We constructed high-resolution spatial transcriptomes of liver biopsies containing 13 059 tissue spots from 18 patients with chronic HBV infection to analyse the occurrence and relative distribution of transcriptionally active viral integration events. Immunohistochemistry was performed to evaluate the expression of HBsAg and HBV core antigen. Intrahepatic covalently closed circular DNA (cccDNA) levels were quantified by real-time qPCR. RESULTS: Spatial transcriptome sequencing identified the presence of 13 154 virus-host chimeric reads in 7.86% (1026 of 13 059) of liver tissue spots in all patients, including three patients with HBsAg loss. These HBV integration sites were randomly distributed on chromosomes and can localise in host genes involved in hepatocarcinogenesis, such as ALB, CLU and APOB. Patients who were receiving or had received antiviral treatment had a significantly lower percentage of viral integration-containing spots and significantly fewer chimeric reads than treatment-naïve patients. Intrahepatic cccDNA levels correlated well with viral integration events. CONCLUSION: Transcriptionally active HBV integration occurred in chronically HBV-infected patients at different phases, including in patients with HBsAg loss. Antiviral treatment was associated with a decreased number and extent of transcriptionally active viral integrations, implying that early treatment intervention may further reduce the number of viral integration events.

Hepatitis B virus middle surface antigen loss promotes clinical variant persistence in mouse models.

Hepatitis B virus (HBV) middle surface antigen (MHBs) mutation or deletion occurs in patients with chronic HBV infection. However, the functional role of MHBs in HBV infection is still an enigma. Here, we reported that 7.33% (11/150) isolates of CHB patients had MHBs start codon mutations compared with 0.00% (0/146) in acute hepatitis B (AHB) patients. Interestingly, MHBs loss accounted for 11.88% (126/1061) isolates from NCBI GenBank, compared with 0.09% (1/1061) and 0.00% (0/1061) for HBV large surface antigen (LHBs) loss and HBV small surface antigen (SHBs) loss, respectively. One persistent HBV clone of genotype B (B56, MHBs loss) from a CHB patient was hydrodynamically injected into BALB/c mice. B56 persisted for >70 weeks in BALB/c mice, whereas B56 with restored MHBs (B56M+) was quickly cleared within 28 days. Serum cytokine assays demonstrated that CXCL1, CXCL2, IL-6 and IL-33 were significantly increased during rapid HBV clearance in B56M+ mice. Furthermore, the enhancers and promoters of B56 were proved to be required for B56 persistence in mice. Ablating MHBs expression improved the persistence of a new clone (HBV1.3, genotype B) which was recreated by using enhancers and promoters of B56. These data demonstrated that MHBs deletion can promote the persistence of specific HBV variants in a hydrodynamic mouse model. MHBs re-expression restored a rapid clearance of HBV, which was accompanied by cytokine responses including the elevation of CXCL1, CXCL2, IL-6 and IL-33.

Serum Levels of ITGBL1 as an Early Diagnostic Biomarker for Hepatocellular Carcinoma with Hepatitis B Virus Infection.

PURPOSE: Early diagnostic biomarkers of hepatocellular carcinoma (HCC) are needed to distinguish hepatitis B virus (HBV) associated HCC (HBV-HCC) patients from at-risk patients. We assessed the diagnostic values of serum Integrin beta-like 1 (ITGBL1) for early-stage HBV-HCC. PATIENTS AND METHODS: We recruited 716 participators including 299 in the training and 417 in the validation stage, (HBV-HCC, chronic hepatitis B (CHB), HBV-related liver cirrhosis (HBV-LC), and healthy controls) between 2017 and 2020 from three centers. Serum ITGBL1 was measured by ELISA. Receiver operating characteristic (ROC) was used to calculate diagnostic accuracy. RESULTS: The serum levels of ITGBL1 in HBV-HCC patients were significantly lower than those in CHB and HBV-LC patients. This result was confirmed in the follow-up patients who progressed from HBV-LC to HCC. The optimum diagnostic cutoff value of serum ITGBL1 was 47.93ng/mL for detection of early-stage HBV-HCC. The serum ITGBL1 has higher diagnostic accuracy than AFP20 in differentiating the early-stage HBV-HCC from the at-risk patients (area under curve [AUC] 0.787 vs 0.638, p<0.05). For AFP-negative (<20ng/mL) HBV-HCC patients, serum ITGBL1 maintained diagnostic accuracy (training cohort: AUC 0.756, 95% confidence interval [CI] 0.683-0.819, sensitivity 68.18%, and specificity 68.85%; validation cohort: 0.744, 0.686-0.796, 81.13%, and 55.88%). Combination ITGBL1 with AFP20 significantly increased diagnostic accuracy in differentiating the HBV-HCC from at-risk patients (AUC 0.840; 0.868) than ITGBL1 (AUC 0.773, p<0.05; 0.732, p<0.0001) or AFP20 (AUC 0.705, p<0.0001; 0.773, p<0.0001) alone. CONCLUSION: The serum level of ITGBL1 improved identification of AFP-negative HBV-HCC patients, and increased diagnostic accuracy with AFP20 together in the early detection of HBV-HCC.

Viral quasispecies quantitative analysis: a novel approach for appraising the immune tolerant phase of chronic hepatitis B virus infection.

Few non-invasive models were established for precisely identifying the immune tolerant (IT) phase from chronic hepatitis B (CHB). This study aimed to develop a novel approach that combined next-generation sequencing (NGS) and machine learning algorithms using our recently published viral quasispecies (QS) analysis package. 290 HBeAg positive patients from whom liver biopsies were taken were enrolled and divided into a training group (n = 148) and a validation group (n = 142). HBV DNA was extracted and QS sequences were obtained by NGS. Hierarchical clustering analysis (HCA) and principal component analysis (PCA) based on viral operational taxonomic units (OTUs) were performed to explore the correlations among QS and clinical phenotypes. Three machine learning algorithms, including K-nearest neighbour, support vector machine, and random forest algorithm, were used to construct diagnostic models for IT phase classification. Based on histopathology, 90 IT patients and 200 CHB patients were diagnosed. HBsAg titres for IT patients were higher than those of CHB patients (p < 0.001). HCA and PCA analysis grouped IT and CHB patients into two distinct clusters. The relative abundance of viral OTUs differed mainly within the BCP/precore/core region and was significantly correlated with liver inflammation and fibrosis. For the IT phase classification, all machine-learning models showed higher AUC values compared to models based on HBsAg, APRI, and FIB-4. The relative abundance of viral OTUs reflects the severity of liver inflammation and fibrosis. The novel QS quantitative analysis approach could be used to diagnose IT patients more precisely and reduce the need for liver biopsy.

ITGBL1 promotes cell migration and invasion through stimulating the TGF-ß signalling pathway in hepatocellular carcinoma.

OBJECTIVES: Integrin beta-like 1 (ITGBL1) is involved in the migration and invasion of several cancers; however, its roles in the development and progression of hepatocellular carcinoma (HCC) remain largely unknown. MATERIALS AND METHODS: Immunohistochemistry staining was used to investigate the expression pattern of ITGBL1 and its prognostic values in HCC patients. The transwell, wound-healing assays, xenograft and orthotopic mouse models were employed to determine the effects of ITGBL1 on HCC cell migration and invasion in vitro and in vivo. The biological mechanisms involved in cell migration and invasion caused by ITGBL1 were determined with Western blotting and RT-PCR methods. RESULTS: ITGBL1 expression was significantly increased in HCC tissues compared to adjacent normal tissues. Patients with higher ITGBL1 expression were associated with more reduced overall survival. ITGBL1 overexpression promoted migration and invasion in SMMC-7721 and HepG2 cells in vitro and in vivo, whereas knockdown or knockout ITGBL1 in CSQT-2 cells significantly reduced cell migration and invasion abilities. In SMMC-7721 cells, ITGBL1 overexpression stimulated TGF-ß/Smads signalling pathway, along with the KRT17 and genes involved in the epithelial-mesenchymal transition (EMT). In contrast, ITGBL1 knockout inhibited the TGF-ß/Smads signalling pathway in CSQT-2 cells. CONCLUSIONS: These findings suggested that ITGBL1 promoted migration and invasion in HCC cells by stimulating the TGF-ß/Smads signalling pathway. ITGBL1 could be a promising prognostic biomarker, as well as a potential therapeutic target in HCC.

Liraglutide prevents ß-cell apoptosis via inactivation of NOX2 and its related signaling pathway.

AIMS: High glucose (HG)-induced pancreatic ß-cell apoptosis may be a major contributor to the progression of diabetes mellitus (DM). NADPH oxidase (NOX2) has been considered a crucial regulator in ß-cell apoptosis. This study was designed to evaluate the impact of GLP-1 receptor agonist (GLP-1Ra) liraglutide on pancreatic ß-cell apoptosis in diabetes and the underlying mechanisms involved. METHODS: The diabetic rat models induced by streptozotocin (STZ) and a high fat diet (HFD) received 12 weeks of liraglutide treatment. Hyperglycemic clamp test was carried out to evaluate ß-cell function in vivo. Flow cytometry analysis was used to measure apoptosis rates in vitro. DCFH-DA method was used to detected ROS level in vivo and in vitro. RESULTS: Liraglutide significantly improved islet function and morphology in diabetic rats and decreased cell apoptosis rates. Thr183/Thr185 p-JNK1/2 and NOX2 levels reduced in diabetic rats and HG-induced INS-1 cell following liraglutide treatment. In addition, liraglutide upregulated the phosphorylation of AMPKα (p-AMPKα), which prevented NOX2 activation and alleviated HG-induced ß-cell apoptosis. CONCLUSION: The p-AMPKα/NOX2/JNK1/2 pathway is essential for liraglutide to attenuate HG-induced ß-cell apoptosis, which further proves that GLP-1Ras may become promising therapeutics for diabetes mellitus.

Protective Effects of Reduced Beta 2 Glycoprotein I on Liver Injury in Streptozotocin (STZ)-Diabetic Rats by Activation of AMP-Activated Protein Kinase.

BACKGROUND Protective effects of reduced beta 2 glycoprotein I (Rb2GPI) against vascular injury of diabetes mellitus have been extensively investigated. However, the effects of Rb2GPI on liver injury in diabetic animals have not been reported. MATERIAL AND METHODS A diabetic rat model of was produced by systemic injection of streptozotocin (STZ). Rats were divided into a normal control group, a model group, and an Rb2GPI treatment group (N=6 in each group). After treatments, blood serum and liver tissue were collected to test the protection of Rb2GPI. AMP-activated protein kinase (AMPK) was detected by immunohistochemistry and Western blotting. RESULTS Our results revealed that Rß2GPI reduced blood glucose, serum creatinine, and urea nitrogen levels, as well as serum inflammation cytokines, including interleukin (IL)-6, tumor necrosis factor (TNF)-α and C-reactive protein in the diabetic rats. Importantly, Rß2GPI prevented liver injury in the diabetic rats as confirmed by hematoxylin-eosin (H&E) staining, alanine transaminase, aspartate transaminase, and gamma-glutamyl transferase. Reactive oxygen species (ROS) were promoted by diabetic modeling and were attenuated by Rß2GPI administration. Moreover, Rß2GPI significantly reduced liver catalase, malondialdehyde, and superoxide dismutase levels in the diabetic rats. Rß2GPI reduced liver glycolipid storage in STZ diabetic rats. Both immunohistochemistry and Western blotting demonstrated that Rß2GPI promoted AMPK phosphorylation in the diabetic rats. CONCLUSIONS Our data proved that Rß2GPI prevented liver injury in diabetic rats, likely through activating the AMPK signaling pathway.

Serum M2BPGi level is a novel predictive biomarker for the responses to pegylated interferon-α treatment in HBeAg-positive chronic hepatitis B patients.

Serum Mac-2-binding protein glycosylation isomer (M2BPGi) level was found to be a useful prognostic marker for hepatitis B e antigen (HBeAg)-positive chronic hepatitis B (CHB) patients treated with nucleoside/nucleotide analogs (NUCs) therapy, and the aim of our study is to evaluate the clinical implementation of M2BPGi level in the prediction of antiviral responses to pegylated-interferon-α (PEG-IFN-α) treatment in HBeAg-positive CHB patients. Ninety-six CHB patients who received PEG-IFN-α treatment for at least 48 weeks were recruited. The serum M2BPGi, alanine aminotransferase (ALT), hepatitis B surface antigen (HBsAg), HBeAg, and HBV DNA levels at baseline, weeks 4, 12, and 24 after PEG-IFN-α treatment were determined and their associations with antiviral responses were evaluated and the virological response (VR) rate and serological response (SR) rate after 48 weeks of treatment were 65.6% and 35.4%, respectively. Baseline serum M2BPGi level was significantly different between VR and non-VR (P = 0.002) or SR and non-SR groups (P = 0.012). Multivariate analyses suggested that baseline serum M2BPGi level was independently associated with VR and SR of PEG-IFN-α treatment at week 48. The area under the ROC curve (AUC) of baseline M2BPGi was 0.682 in predicting VR, which was superior to HBsAg (AUC = 0.566) or HBV DNA (AUC = 0.567). The AUC of baseline M2BPGi in predicting SR was 0.655, which was also higher than that of HBsAg (AUC = 0.548) or HBV DNA (AUC = 0.583). These results suggested that baseline serum M2BPGi level was a novel predictor of VR and SR for PEG-IFN-α treatment in HBeAg-positive CHB patients.

Effects of reduced ß2 glycoprotein I on high glucose­induced cell death in HUVECs.

Reduced ß2 glycoprotein I (ß2GPI) has been demonstrated to exhibit a beneficial effect in diabetic atherosclerosis and retinal neovascularization. However, the effect of reduced ß2GPI on vascular disorders in diabetic mellitus (DM) remains to be elucidated. The present study established a high glucose­induced injury model using human umbilical cords veins (HUVECs) and evaluated the protective effects of reduced ß2GPI against the injury. The data demonstrated that a low concentration of reduced ß2GPI (0.5 µM) mitigated high glucose­induced cell loss, decreased nitric oxide (NO) production and resulted in calcium overloading. Mechanically, reduced ß2GPI additionally reversed high glucose­induced phosphatase and tensin homolog (PTEN) accumulation, decrease of protein kinase B phosphorylation and nitric oxide synthase activity, and increase of cyclooxygenase­2 activity. It was further confirmed that PTEN inhibitor­bpV (1 µM) exhibited similar effects to those resulting from reduced ß2GPI. Overall, the data revealed that reduced ß2GPI exerts protective effects from glucose­induced injury in HUVECs, potentially via decreasing PTEN levels. The present study suggests reduced ß2GPI may act as a novel therapeutic strategy for the treatment of vascular disorders in DM.

Characterization of gene expression profiles in HBV-related liver fibrosis patients and identification of ITGBL1 as a key regulator of fibrogenesis.

Although hepatitis B virus (HBV) infection is the leading cause of liver fibrosis (LF), the mechanisms underlying liver fibrotic progression remain unclear. Here, we investigated the gene expression profiles of HBV-related LF patients. Whole genome expression arrays were used to detect gene expression in liver biopsy samples from chronically HBV infected patients. Through integrative data analysis, we identified several pathways and key genes involved in the initiation and exacerbation of liver fibrosis. Weight gene co-expression analysis revealed that integrin subunit ß-like 1 (ITGBL1) was a key regulator of fibrogenesis. Functional experiments demonstrated that ITGBL1 was an upstream regulator of LF via interactions with transforming growth factor ß1. In summary, we investigated the gene expression profiles of HBV-related LF patients and identified a key regulator ITGBL1. Our findings provide a foundation for future studies of gene functions and promote the development of novel antifibrotic therapies.

Serum WFA+ -M2BP levels for evaluation of early stages of liver fibrosis in patients with chronic hepatitis B virus infection.

BACKGROUND & AIMS: Accurate evaluation of liver fibrosis is crucial for predicting progression of chronic hepatitis B virus (HBV) infection. We assessed the utility of a novel fibrosis glycobiomarker Wisteria floribunda agglutinin-positive Mac-2-binding protein (WFA+ -M2BP) for evaluating liver fibrosis and disease progression in patients with chronic HBV infection. METHODS: We enrolled 774 patients with chronic HBV infection, with or without fibrosis, diagnosed by liver biopsy/FibroScan. Patients who underwent liver biopsy (n = 297) were divided into training (n = 221) and validation (n = 76) groups. Serum WFA+ -M2BP values were measured and compared with FIB-4 index, aspartate aminotransferase (AST)-to-platelet ratio (APRI) and AST-to-alanine aminotransferase ratio (AAR) using receiver-operating characteristic (ROC) analysis. RESULTS: Serum WFA+ -M2BP levels increased significantly with fibrosis progression (P < 0.0001). Area under the ROC curve of WFA+ -M2BP for diagnosing significant fibrosis was higher than that of FIB-4 (P = 0.198), APRI (P = 0.017) and AAR (P < 0.001), with sensitivity and specificity in the training set of 60.5% and 79.8% and validation set of 59.5% and 82.1%, respectively. Serum WFA+ -M2BP levels were significantly correlated with FibroScan values (P < 0.0001) and improved the accuracy of FibroScan in assessing significant fibrosis. Changes in WFA+ -M2BP levels were parallel with those in FibroScan values during nucleot(s)ide analogues therapy in patients with chronic HBV infection. CONCLUSIONS: WFA+ -M2BP is an accurate serum indicator for assessing early stages of liver fibrosis and may monitor regression of fibrosis during the treatment of chronic HBV infection. WFA+ -M2BP provides a simple and reliable alternative or complementary method to liver biopsy and FibroScan.

Redox Status of ß2GPI in Different Stages of Diabetic Angiopathy.

We explored the redox status of beta 2 glycoprotein I (ß2GPI) in different stages of diabetic angiopathy. Type 2 diabetes mellitus (T2DM) had a significantly lower proportion of reduced ß2GPI as compared to healthy controls (p < 0.05). There was a trend that the mild coronal atherosclerosis heart disease (CAD) had higher proportion of reduced ß2GPI than non-CAD and severe-CAD groups, however without significances (p > 0.05). The mild-A-stenosis group and mild-diabetic retinopathy (DR) groups had higher proportion of reduced ß2GPI than their severely affected counterparts. The mild-slow nerve conduction velocity (NCVS) group had higher proportion of reduced ß2GPI than normal nerve conduction velocity (NCVN group) and severe-NCVS groups. The proportion of reduced ß2GPI was in positive correlation with 24 h urine microalbumin and total urine protein, and the proportion of reduced ß2GPI was in negative correlation with serum and skin advanced glycation end products (AGEs). Taken together, our data implicate that the proportion of reduced ß2GPI increased in the early stage of angiopathy and decreased with the aggravation of angiopathy.

C­reactive protein/oxidized low density lipoprotein/ß2­glycoprotein i complexes induce lipid accumulation and inflammatory reaction in macrophages via p38/mitogen­activated protein kinase and nuclear factor­κB signaling pathways.

Oxidized low-density lipoprotein (oxLDL) can bind to ß2-glycoprotein I (ß2GPI) and C-reactive protein (CRP) to form stable complexes, which exert certain effects in diabetic cardiovascular disease. A previous study by our group has confirmed that the resulting complexes promote atherosclerosis in diabetic BALB/c mice. The present study was designed to investigate the effects and potential mechanisms of oxLDL complexes on lipid accumulation and inflammatory reactions in RAW264.7 macrophages cultured in a hyperglycemic environment. Cultured cells were divided into seven groups, which were treated with phosphate­buffered saline (control), CRP, ß2GPI, oxLDL, CRP/oxLDL, oxLDL/ß2GPI or CRP/oxLDL/ß2GPI. The results revealed the formation of foam cells in the oxLDL, CRP/oxLDL, oxLDL/ß2GPI as well as CRP/oxLDL/ß2GPI groups. Compared with oxLDL, the three complexes induced less lipid accumulation (P<0.05) through inhibiting the expression of CD36 mRNA and promoting the expression of and ABCG1 mRNA (P<0.05 vs. oxLDL). Furthermore, the levels of inflammatory factors interleukin (IL)­1ß, IL­6 and tumor necrosis factor­α were elevated in the CRP/oxLDL and CRP/oxLDL/ß2GPI groups (P>0.05 vs. oxLDL), and obvious effects on p38/mitogen­activated protein kinase and nuclear factor (NF)­κB phosphorylation were also observed in these groups (P<0.05 vs. oxLDL). These results suggested that CRP/oxLDL/ßG2P1 complexes may induce lipid accumulation and inflammation in macrophages via the p38/MAPK and NF­κB signaling pathways. However, some differences were observed between the complexes, which may be attributed to the property of each constituent; therefore, further studies are required.

Decreased secretion of adiponectin through its intracellular accumulation in adipose tissue during tobacco smoke exposure.

BACKGROUND: Cigarette smoking is associated with an increased risk of type 2 diabetes mellitus (T2DM). Smokers exhibit low circulating levels of total adiponectin (ADPN) and high-molecular-weight (HMW) ADPN multimers. Blood concentrations of HMW ADPN multimers closely correlate with insulin sensitivity for handling glucose. How tobacco smoke exposure lowers blood levels of ADPN, however, has not been investigated. In the current study, we examined the effects of tobacco smoke exposure in vitro and in vivo on the intracellular and extracellular distribution of ADPN and its HMW multimers, as well as potential mechanisms. FINDINGS: We found that exposure of cultured adipocytes to tobacco smoke extract (TSE) suppressed total ADPN secretion, and TSE administration to mice lowered their plasma ADPN concentrations. Surprisingly, TSE caused intracellular accumulation of HMW ADPN in cultured adipocytes and in the adipose tissue of wild-type mice, while preferentially decreasing HMW ADPN in culture medium and in plasma. Importantly, we found that TSE up-regulated the ADPN retention chaperone ERp44, which colocalized with ADPN in the endoplasmic reticulum. In addition, TSE down-regulated DsbA-L, a factor for ADPN secretion. CONCLUSIONS: Tobacco smoke exposure traps HMW ADPN intracellularly, thereby blocking its secretion. Our results provide a novel mechanism for hypoadiponectinemia, and may help to explain the increased risk of T2DM in smokers.

The sero-prevalence of anti-adenovirus 5 neutralizing antibodies is independent of a chronic hepatitis B carrier state in China.

We investigated the prevalence of neutralizing antibodies (NA) to human Adenovirus (Ad) 5 both in healthy subjects (HS) and Chronic Hepatitis B (CHB) patients in Shanghai. Detection of anti-Ad5 NA (percentage of detection and titers) was similar between HS and CHB patients. A high percentage of subjects harbored no detectable antibodies (32.2 %) while proportion of subjects displaying very high antibody titers was low (4 %). Neither demographic factors (gender, age, health) nor AST/ALT or HBV circulating DNA titers affected detection of Ad5-specific NA. These observations pave the ground for development of Ad5-based immunotherapeutics aiming at treating CHB patients in China.

Chemerin expression in Chinese pregnant women with and without gestational diabetes mellitus.

OBJECTIVES: The aim of this study was to determine the effect of obesity, gestational diabetes mellitus (GDM) on circulating chemerin concentrations and chemerin gene expression of adipotissue in pregnancy women. MATERIAL AND METHODS: Totally 42 normal glucose tolerant (NGT) women and 48 women with GDM were included in this study. Their clinical features and biochemical parameters were analyzed. The NGT and GDM women were subgrouped by prepregnancy BMI as normal-weight group, overweight group, and obese group, respectively. Serum chemerin and tumor necrosis factor α (TNF-α) of these individuals were determined by ELISA methods, and subcutaneous adipose tissues' mRNA expressions of chemerin and CMKLR1 (encoding the receptor of chemerin) were analyzed by real-time PCR. RESULTS: Serum chemerin in obese-NGT group and normal-weight-GDM group was significantly higher than that of normal-weight-NGT group. Chemerin and CMKLR1 mRNA expression of subcutaneous adipose tissue was lower in the obese-NGT group than normal-weight-NGT group. There was no significant difference of CMKLR1 mRNA expression between normal-weight-NGT and normal-weight-GDM group. Serum chemerin significantly and positively correlated with triglycerides (TG) and homeostasis model assessment of insulin resistance (HOMA-IR) assessed both by uni- and multivariate. CONCLUSIONS: Gestational obesity, GDM may contribute to the elevating serum chemerin. Serum chemerin in pregnancy was associated with insulin resistance and triglycerides. Chemerin gene may play a role both in obese and GDM patients. CMKLR1 might exert its action only in obese individuals, not in GDM patients before delivery.

Hepatitis B virus core protein sensitizes hepatocytes to tumor necrosis factor-induced apoptosis by suppression of the phosphorylation of mitogen-activated protein kinase kinase 7.

UNLABELLED: Hepatitis B, which caused by hepatitis B virus (HBV) infection, remains a major health threat worldwide. Hepatic injury and regeneration from chronic inflammation are the main driving factors of liver fibrosis and cirrhosis in chronic hepatitis B. Proinflammatory tumor necrosis factor alpha (TNF-α) has been implicated as a major inducer of liver cell death during viral hepatitis. Here, we report that in hepatoma cell lines and in primary mouse and human hepatocytes, expression of hepatitis B virus core (HBc) protein made cells susceptible to TNF-α-induced apoptosis. We found by tandem affinity purification and mass spectrometry that receptor of activated protein kinase C 1 (RACK1) interacted with HBc. RACK1 was recently reported as a scaffold protein that facilitates the phosphorylation of mitogen-activated protein kinase kinase 7 (MKK7) by its upstream activators. Our study showed that HBc abrogated the interaction between MKK7 and RACK1 by competitively binding to RACK1, thereby downregulating TNF-α-induced phosphorylation of MKK7 and the activation of c-Jun N-terminal kinase (JNK). In line with this finding, specific knockdown of MKK7 increased the sensitivity of hepatocytes to TNF-α-induced apoptosis, while overexpression of RACK1 counteracted the proapoptotic activity of HBc. Capsid particle formation was not obligatory for HBc proapoptotic activity, as analyzed using an assembly-defective HBc mutant. In conclusion, the expression of HBc sensitized hepatocytes to TNF-α-induced apoptosis by disrupting the interaction between MKK7 and RACK1. Our study is thus the first indication of the pathogenic effects of HBc in liver injury during hepatitis B. IMPORTANCE: Our study revealed a previously unappreciated role of HBc in TNF-α-mediated apoptosis. The proapoptotic activity of HBc is important for understanding hepatitis B pathogenesis. In particular, HBV variants associated with severe hepatitis may upregulate apoptosis of hepatocytes through enhanced HBc expression. Our study also found that MKK7 is centrally involved in TNF-α-induced hepatocyte apoptosis and revealed a multifaceted role for JNK signaling in this process.

Domain I-IV of ß2-glycoprotein I inhibits advanced glycation end product-induced angiogenesis by down-regulating vascular endothelial growth factor 2 signaling.

Advanced glycation end products (AGEs) are a contributing factor in the angiogenesis that is characteristic of proliferative diabetic retinopathy. However, a previous study made a promising observation that domain I­IV of ß2­glycoprotein I (DI­IV) inhibits angiogenesis in human umbilical vein cells. The present study aimed to confirm the inhibition of AGE­induced angiogenesis in retinal endothelial cells by DI­IV and to investigate the potential underlying mechanisms. The RF/6A rhesus macaque choroid­retinal vascular endothelial cell line was cultured in vitro and treated with AGEs in the presence or absence of different concentrations of DI­IV. The proliferation, migration and tube formation of the RF/6A cells were evaluated using MTS assays, in vitro wound healing assays and in vitro Matrigel angiogenesis assays, respectively. The mRNA expression of vascular endothelial growth factor (VEGF), VEGF receptor (VEGFR) 2, VEGFR 1 and receptor for AGE (RAGE) were quantified by reverse transcription quantitative polymerase chain reaction. The expression of VEGFR­1, VEGFR­2 and the activation of protein kinase B (Akt) and extracellular signal­regulated kinase (ERK) were also assessed by western blot analysis. The results indicated that AGEs promoted the migration, proliferation and tube formation of RF/6A cells in vitro (P<0.05), increased the expression of VEGF, VEGFR­2 and RAGE (P<0.05) and increased the phosphorylation of Akt and ERK (P<0.05). DI­IV inhibited the increase in VEGFR­2 mRNA and protein, but did not inhibit the increase in VEGF or RAGE mRNAs. These results led to the conclusion that DI­IV inhibited AGE­induced angiogenesis in the RF/6A cells, which was accompanied by a downregulation in the expression of VEGFR­2 and its downstream phosphatidylinosol 3­kinase/Akt and mitogen­activated protein kinase/ERK1/2 pathways. These findings provide further support towards the treatment of proliferative diabetic retinopathy by interventions that act via a mechanism similar to that of DI­IV.

Reduced ß­2­glycoprotein І inhibits hypoxia­induced retinal angiogenesis in neonatal mice through the vascular endothelial growth factor pathway.

ß­2­glycoprotein I (ß2GPI), also known as apolipoprotein H, is a phospholipid­binding plasma protein consisting of five homologous repeated units. ß2GPI downregulates vascular endothelial growth factor (VEGF) signaling pathways and inhibits angiogenesis in vitro. However, the in vivo roles and effectors of reduced ß2GPI and ß2GPI in retinal angiogenesis are still not fully understood. In this study, an oxygen­induced retinopathy model was used to investigate the effects of reduced ß2GPI and ß2GPI, and to monitor the expression of VEGF, VEGF receptor (VEGFR) 1, VEGFR­2 and hypoxia­inducible factor 1 (HIF­1) mRNA and the phosphorylation of extracellular signal­regulated kinase (ERK) and Akt. The data showed that both ß2GPI and reduced ß2GPI inhibited retinal angiogenesis and suppressed the expression of VEGF, VEGFR­1, VEGFR­2, HIF­1, phosphorylated- (p­) ERK and p­Akt. The effects of reduced ß2GPI were significantly stronger than those of ß2GPI. In conclusion, this study showed that ß2GPI and reduced ß2GPI could inhibit retinal angiogenesis by downregulating the expression of VEGF and its downstream targets. This suggests that ß2GPI and reduced ß2GPI may have potential anti­angiogenic activity in vivo.