I-Chin Wu

Very low-density lipoprotein/lipo-viro particles reverse lipoprotein lipase-mediated inhibition of hepatitis C virus infection via apolipoprotein C-III

Objective Circulating hepatitis C virus (HCV) virions are associated with triglyceride-rich lipoproteins, including very low-density lipoprotein (VLDL) and low-density lipoprotein (LDL), designated as lipo-viro-particles (LVPs). Previous studies showed that lipoprotein lipase (LPL), a key enzyme for hydrolysing the triglyceride in VLDL to finally become LDL, may suppress HCV infection. This investigation considers the regulation of LPL by lipoproteins and LVPs, and their roles in the LPL-mediated anti-HCV function. Design The lipoproteins were fractionated from normolipidemic blood samples using iodixanol gradients. Subsequent immunoglobulin-affinity purification from the canonical VLDL and LDL yielded the corresponding VLDL-LVP and LDL-LVP. Apolipoprotein (apo) Cs, LPL activity and HCV infection were quantified. Results A higher triglyceride/cholesterol ratio of LDL was found more in HCV-infected donors than in healthy volunteers, and the triglyceride/cholesterol ratio of LDL-LVP was much increased, suggesting that the LPL hydrolysis of triglyceride may be impaired. VLDL, VLDL-LVP, LDL-LVP, but not LDL, suppressed LPL lipolytic activity, which was restored by antibodies that recognised apoC-III/-IV and correlated with the steadily abundant apoC-III/-IV quantities in those particles. In a cell-based system, treatment with VLDL and LVPs reversed the LPL-mediated inhibition of HCV infection in apoC-III/-IV-dependent manners. A multivariate logistic regression revealed that plasma HCV viral loads correlated negatively with LPL lipolytic activity, but positively with the apoC-III content of VLDL. Additionally, apoC-III in VLDL was associated with a higher proportion of HCV-RNA than was IgG. Conclusion This study reveals that LPL is an anti-HCV factor, and that apoC-III in VLDL and LVPs reduces the LPL-mediated inhibition of HCV infection.

Association of intrahepatic cccDNA reduction with the improvement of liver histology in chronic hepatitis B patients receiving oral antiviral agents.

Covalently closed circular DNA (cccDNA) of hepatitis B virus (HBV) is difficult to eradicate using current antiviral therapy. This study compares cccDNA reduction with relation to liver histology in nucleoside/nucleotide‐naïve chronic hepatitis B patients receiving oral antiviral monotherapy (n = 35), including entecavir (ETV, n = 13), adefovir dipivoxil (ADV, n = 22) or placebo (n = 14). Serum HBV DNA, intrahepatic total HBV DNA and cccDNA are quantified. Histological hepatic examination is performed at baseline and at 48 weeks of treatment. Treatment with ETV or ADV shows significant median reduction in serum HBV DNA (−6.21 and −4.27 log10 copies/mL) and intrahepatic total HBV DNA (−1.69 and −1.23 log10 copies/cell). Intrahepatic cccDNA levels are reduced slightly in the ETV and the ADV groups, but do not differ statistically from the placebo group (−0.17 vs. −0.01 vs. 0.02 copies/cell). Only the level of intrahepatic cccDNA correlates with Knodell necroinflammation activity (r = 0.527, P < 0.001) and Ishak fibrosis severity (r = 0.348, P = 0.015) before treatment. Multivariate logistic regression analysis indicates that treatment‐induced cccDNA reduction is associated with improved necroinflammation (P = 0.041) and fibrosis (P = 0.026). In conclusion, baseline intrahepatic cccDNA loads correlate with histologic activity. Although one‐year ETV or ADV treatment is insufficient for cccDNA eradication, oral antiviral therapies may improve liver histology, probably by suppressing intrahepatic cccDNA. J. Med. Virol. 83:602–607, 2011.

Apolipoprotein J, a glucose-upregulated molecular chaperone, stabilizes core and NS5A to promote infectious hepatitis C virus virion production

BACKGROUND & AIMS Hepatitis C virus (HCV) infection leads to glucose abnormality. HCV depends on lipid droplets (LDs) and very-low density lipoproteins for assembly/releasing; however, the components and locations for this process remain unidentified. Apolipoprotein J (ApoJ), upregulated by glucose, functions as Golgi chaperone of secreted proteins and resides abundantly in very-low density lipoproteins. This study investigates the interplay between glucose, ApoJ and HCV virion production. METHODS The effects of high glucose on ApoJ expression and HCV production were evaluated with cultivated HuH7.5, primary human hepatocytes, and in treatment naive chronic hepatitis C patients. How ApoJ affects HCV lifecycle was assessed using siRNA knockdown strategy in JFH1 infected and subgenomic replicon cells. The interactions and locations of ApoJ with viral and host components were examined by immunoprecipitation, immunofluorescence and subcellular fractionation experiments. RESULTS HCV infection increased ApoJ expression, which in parallel with HCV infectivity was additionally elevated with high glucose treatment. Serum ApoJ correlated positively with fasting blood glucose concentration and HCV-RNA titre in patients. ApoJ silencing reduced intracellular and extracellular HCV infectivity and extracellular HCV-RNA, but accumulated intracellular HCV-RNA in HCV-infected cells. ApoJ interacted with HCV core and NS5A and stabilized the dual protein complex. HCV infection dispersed cytoplasmic ApoJ from the compact zones of the Golgi to encircle LDs, where co-localization of the core, NS5A, HCV-RNA, subcellular markers for LDs, endoplasmic reticulum (ER), Golgi, and membrane contact sites occurred. CONCLUSIONS ApoJ facilitates infectious HCV particle production via stabilization of core/NS5A, which might surround LDs at the ER-Golgi membrane contact site.

Genotyping of Hepatitis B Virus – Genotypes A to G by Multiplex Polymerase Chain Reaction

Objectives: Eight genotypes (A–H) of hepatitis B virus (HBV) are known with variations in nucleotide sequences greater than 8%. Several recent publications found that the clinical course and outcome of antiviral therapy depended on the genotype of the infecting HBV strain. Large epidemiological studies will require the availability of a system which is rapid, reliable and can be performed on a large number of samples. Methods: To establish a simple and accurate genotyping method, the study collected 369 HBV complete genomic sequences from the GenBank database. Type-specific primers were also designed that separated HBV genotypes A to G by multiplex polymerase chain reaction. Results: By comparison with the traditional restriction fragment length polymorphism method, over 93% of 441 samples were accurately genotyped by current assay, with a higher detection rate and sensitivity to detect mixed HBV infections. Conclusions: This methodology can be applied only to areas prevalent with HBV genotypes A to G. However, it provides an efficient alternative for clinical diagnosis and large-scale studies.

Low dose erythropoietin-beta improves anemia and maintains ribavirin dose in chronic hepatitis C patients receiving combination therapy with ribavirin plus pegylated interferon Alfa-2b.

Aim:  Anemia during combination therapy with pegylated interferon alfa‐2b plus ribavirin (RBV) for chronic hepatitis C virus (HCV) patients usually leads to RBV dose reduction or discontinuation. This study evaluated the effect of erythropoietin‐beta (EPO‐β) to maintain RBV dose and hemoglobin (Hb) level in chronic HCV patients treated with antiviral combination therapy.

Aberrant Serum Immunoglobulin G Glycosylation in Chronic Hepatitis B Is Associated With Histological Liver Damage and Reversible by Antiviral Therapy

BACKGROUND Aberrant serum immunoglobulin G (IgG) glycosylation and its immunomodulatory effect are rarely addressed in chronic hepatitis B virus (HBV) infection. METHODS Serum IgG-Fc glycosylation profiles in 76 patients with HBV-related liver cirrhosis and 115 patients with chronic hepatitis B (CHB) before and after 48 weeks of anti-HBV nucleos(t)ide analogue treatment were analyzed using high-throughput liquid chromatography-mass spectrometry and were compared to profiles in 108 healthy controls. RESULTS The level of aberrant serum IgG-Fc glycosylation ,: particularly galactose deficiency, was higher in patients with CHB and those with cirrhosis (P < .001 for both) than in healthy controls. IgG galactose deficiency was correlated with the severity of liver necroinflammation and fibrosis in CHB. Multivariate logistic regression analyses showed that the IgG-Fc glycoform with fucosylation and fully galactosylation was an independent factor for a total Knodell necroinflammation score of ≥ 7 (odds ratio, 0.74; 95% confidence interval, .56-.97) and an Ishak fibrosis score of ≥ 3 (odds ratio, 0.69; 95% confidence interval, .49-.97). Administration of antiviral therapy for 48 weeks reversed aberrant IgG-Fc glycosylation in patients with CHB from week 12 onward but did not reverse glycosylation in patients with cirrhosis. Attenuated IgG opsonization in patients with CHB, which was correlated with aberrant Fc-glycosylation, was reversed after treatment as well. CONCLUSIONS Aberrant serum IgG-Fc glycosylation in CHB, which is highly associated with histological liver damage, affects IgG opsonizing activity and can be reversed by antiviral therapy.

Clinical significance of serum HBsAg levels and association with liver histology in HBeAg positive chronic hepatitis B.

BACKGROUND Despite its recognized role as a prognostic marker for antiviral treatment, the clinical significance of serum hepatitis B surface antigen (HBsAg) level in the immune-clearance stage of chronic hepatitis B remains unclear. OBJECTIVES To characterize how HBsAg level and various clinical and virological factors are related and analyze the correlation of HBsAg with liver histology. STUDY DESIGN A total of 198 treatment-naïve HBeAg-positive chronic hepatitis B patients were enrolled. Serum HBV DNA and HBsAg were determined quantitatively. Mutations of precore or basal core promoter (BCP) were also determined. Finally, liver necroinflammation grading and fibrosis stage were evaluated by Knodell score and Ishak score, respectively. RESULTS Lower HBsAg levels were found in patients with genotype C HBV infection, or in the presence of precore or mutations, or Knodell necroinflammation grading ≥ 7, or advanced fibrosis (Ishak stage 4-6). HBsAg level displayed a strong correlation with HBV DNA (r = 0.727, P < 0.001) and also exhibited a positive correlation with intrahepatic HBcAg expression in either cytoplasm (r = 0.420, P < 0.001) or nucleus (r = 0.401, P < 0.001). Examining the correlation with advanced liver fibrosis revealed that HBsAg level is a significant factor in univariate analysis and is the only independent factor in multivariate analysis (Coefficient: -0.975, P = 0.039, OR: 0.377, 95% CI: 0.149-0.953). CONCLUSIONS HBsAg level varied with different clinical or virological categories. Lower baseline levels of HBsAg might reflect the status of advanced liver fibrosis in HBeAg positive chronic hepatitis B patients.

Resistance of ground glass hepatocytes to oral antivirals in chronic hepatitis B patients and implication for the development of hepatocellular carcinoma

Ground glass hepatocytes (GGHs) have been shown to predict the development of hepatocellular carcinoma (HCC). Type I GGH and type II GGH harbor hepatitis B virus (HBV) pre-S1 and pre-S2 deletion mutants, respectively. Whether anti-HBV therapy can inhibit the expression of GGHs and potentially reduce HCC development is explored in this study. Two sets of liver specimens were included: the first contained 31 paired biopsy specimens obtained from chronic HBV patients receiving oral nucleos(t)ide analogue (NA) treatment; the second contained 186 resected liver tissues obtained from HBV-related HCC patients receiving surgery: 82 received NA before surgery and 104 did not. Compared with the baseline biopsy specimens, type I (P=0.527) and type II GGH (P=0.077) were not significantly decreased after 48 weeks of NA treatment in the first set of patients. In the second set, despite suppression of viral load (P<0.001) and periportal necrosis (P=0.006) in treated patients, GGH (P=0.594), cccDNA (P=0.172) and serum pre-S mutants (p=0.401) were not significantly suppressed. A significant decrease of type I (P=0.049) and type II GGH (P=0.029) could only be observed in patients after long duration of treatment (median duration: 4.3 years). In the treated patients, the persisted type II GGH remained an independent variable associated with decreased local recurrence-free survival of HCC (P=0.019) as in non-treated patients (P=0.001). In conclusion, the persistence of GGHs could explain the residual risk of HCC development under anti-HBV treatment. Therefore, intrahepatic GGHs and pre-S mutant are potential additional targets for HCC prevention in patients already receiving anti-HBV treatment.

Analysis of precore/core covariances associated with viral kinetics and genotypes in hepatitis B e antigen-positive chronic hepatitis B patients

Hepatitis B virus (HBV) is one of the most common DNA viruses that can cause aggressive hepatitis, cirrhosis and hepatocellular carcinoma. Although many people are persistently infected with HBV, the kinetics in serum levels of viral loads and the host immune responses vary from person to person. HBV precore/core open reading frame (ORF) encoding proteins, hepatitis B e antigen (HBeAg) and core antigen (HBcAg), are two indicators of active viral replication. The aim of this study was to discover a variety of amino acid covariances in responses to viral kinetics, seroconversion and genotypes during the course of HBV infection. A one year follow-up study was conducted with a total number of 1,694 clones from 23 HBeAg-positive chronic hepatitis B patients. Serum alanine aminotransferase, HBV DNA and HBeAg levels were measured monthly as criteria for clustering patients into several different subgroups. Monthly derived multiple precore/core ORFs were directly sequenced and translated into amino acid sequences. For each subgroup, time-dependent covariances were identified from their time-varying sequences over the entire follow-up period. The fluctuating, wavering, HBeAg-nonseroconversion and genotype C subgroups showed greater degrees of covariances than the stationary, declining, HBeAg-seroconversion and genotype B. Referring to literature, mutation hotspots within our identified covariances were associated with the infection process. Remarkably, hotspots were predominant in genotype C. Moreover, covariances were also identified at early stage (spanning from baseline to a peak of serum HBV DNA) in order to determine the intersections with aforementioned time-dependent covariances. Preserved covariances, namely representative covariances, of each subgroup are visually presented using a tree-based structure. Our results suggested that identified covariances were strongly associated with viral kinetics, seroconversion and genotypes. Moreover, representative covariances may benefit clinicians to prescribe a suitable treatment for patients even if they have no obvious symptoms at the early stage of HBV infection.

Association of serum IgG N-glycome and transforming growth factor-β1 with hepatitis B virus e antigen seroconversion during entecavir therapy.

Aberrant serum IgG N-glycome has been demonstrated in various autoimmune diseases and viral infections. However, the correlation between serum IgG N-glycome and cytokine is unclear. In addition, the clinical relevance of IgG glycosylation and cytokine changes in the treatment outcome of chronic hepatitis B (CHB) has never been assessed. One hundred and three treatment-naive patients with CHB and 101 healthy controls were enrolled in this retrospective cohort study. Serum samples in patients before and after 48weeks of entecavir treatment were collected. In-gel trypsinized serum IgG heavy chain was analyzed using liquid chromatography-tandem mass spectrometry. Selected ion chromatograms corresponding to 10 N-glycoforms on asparagine 297 were individually extracted to calculate the percentage of each glycoforms. Serum cytokine profiles were examined using enzyme-linked immunosorbent assay. Forty-eight weeks of entecavir treatment resulted in decreases in galactose-deficient (total G0) IgG and transforming growth factor (TGF)-β1 levels (both P<0.001) in patients with CHB. The changes in TGF-β1 (ΔTGF-β1) and IgG total G0 (Δtotal G0) levels during treatment were significantly correlated (r=0.403, P<0.001). Furthermore, higher levels of Δtotal G0 (P<0.01) and ΔTGF-β1 (P<0.001) were found in hepatitis B virus e antigen (HBeAg)-positive patients than in HBeAg-negative patients and were also found in patients with HBeAg seroconversion at week 48. The area under the receiver operating characteristic (ROC) curves for Δtotal G0 and ΔTGF-β1 to discriminate a week-48 HBeAg seroconversion were 0.835 and 0.830, respectively. These results suggested a correlation between serum cytokine and IgG N-glycome and its effect on the outcome of entecavir treatment in patients with CHB.