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Background & Aims: The cellular immunity has a profound impact on the status of hepatitis C virus (HCV) infection. However, the response of cellular immunity on the virological response in patients with antiviral treatment remains largely unclear. We aimed to clarify the response of peripheral T cells and monocytes in chronic hepatitis C patients with antiviral treatment. Methods: Patients with chronic hepatitis C were treated either with interferon alpha-2b plus ribavirin (n = 37) or with pegylated interferon alpha-2a plus ribavirin (n = 33) for up to 24 weeks. Frequencies of peripheral regulatory T-cells (Tregs), programmed death-1 (PD-1) expressing CD4+ T-cells or CD8+ T-cells and toll-like receptor (TLR) 3 expressing CD14+ monocytes were evaluated by flow cytometry in patients at baseline, 12 and 24 weeks following treatment and in 20 healthy controls. Results: Frequencies of Tregs, PD-1 and TLR3 expressing cells were higher in patients than those in control subjects (P<0.05). Patients with complete early virological response (cEVR) showed lower Tregs, PD-1 expressing CD4+ or CD8+ T-cells than those without cEVR at 12 weeks (P<0.05). Patients with low TLR3 expressing CD14+ monocytes at baseline had a high rate of cEVR (P<0.05). Conclusions: Low peripheral TLR3 expressing CD14+ monocytes at baseline could serve as a predictor for cEVR of antiviral therapy in chronic HCV-infected patients. The cEVR rates were significantly increased in the patients with reduced circulating Tregs, PD-1 expressing CD4+ or CD8+ T-cells. Trial Registration: Chinese Clinical Trial Registry ChiCTR10001090. [ABSTRACT FROM AUTHOR]

Background: Previously, we have successfully constructed replication-competent hepatitis B virus (HBV) vectors by uncoupling the P open reading frame (ORF) from the preC/C ORF to carefully design the transgene insertion site to overcome the compact organization of the HBV genome and maintain HBV replication competence. Consequently, the replication-competent HBV vectors carrying foreign genes, including pCH-BsdR, carrying blasticidin resistance gene (399 bp), and pCH-hrGFP, carrying humanized renilla green fluorescent protein gene (720 bp), were successfully obtained. However, the replication efficiency of the former is higher but it is tedious to use, while that of the latter is poor and cannot be quantified. Hence, we need to search for a new reporter gene that is convenient and quantifiable for further research., Aim: To establish a helpful tool for intracellular HBV replication and anti-viral drugs screening studies., Methods: We utilized the replication-competent HBV viral vectors constructed by our laboratory, combined with the secreted luciferase reporter gene, to construct replication-competent HBV vectors expressing the reporter gene secretory Nanoluc Luciferase (SecNluc). HepG2.TA2-7 cells were transfected with this vector to obtain cell lines with stably secreted HBV particles carrying secNluc reporter gene., Results: The replication-competent HBV vector carrying the SecNluc reporter gene pCH-sNLuc could produce all major viral RNAs and a full set of envelope proteins and achieve high-level secreted luciferase expression. HBV replication intermediates could be produced from this vector. Via transfection with pTRE-sNLuc and selection by hygromycin, we obtained isolated cell clones, named HBV-NLuc-35 cells, which could secrete secNLuc recombinant viruses, and were sensitive to existing anti-HBV drugs. Using differentiated HepaRG cells, it was verified that recombinant HBV possessed infectivity., Conclusion: Our research demonstrated that a replication-competent HBV vector carrying a secreted luciferase transgene possesses replication and expression ability, and the established HBV replication and expression cell lines could stably secrete viral particles carrying secNluc reporter gene. More importantly, the cell line and the secreted recombinant viral particles could be used to trace HBV replication or infection., Competing Interests: Conflict-of-interest statement: The authors declare no conflicts of interest., (©The Author(s) 2019. Published by Baishideng Publishing Group Inc. All rights reserved.)

B7-H4, another member of costimulatory molecule, has been shown to be overexpressed in multiple types of tumors, including hepatocellular carcinoma (HCC). However, the specific biological role of B7-H4 in HCC still needs to be further explored. In this study, we observed that B7-H4 was highly overexpressed in HCC tissues and cells, and its overexpression strongly correlated with patient's TNM stage, overall survival and early recurrence. Downregulation of B7-H4 significantly suppressed cell growth, invasion, and stemness of HCC by inducing apoptosis in the in vitro experiment. In addition, depletion of B7-H4 could help restore CD8 + T anti-tumor immunity by elevating the expression and secretion levels of CD107a, granzyme A, granzyme B, perforin and IFN-γ. In a xenografted mouse model of HCC, stable depletion of B7-H4 resulted in significantly smaller mean tumor volume and less mean tumor weight after 30 days of growth, compared to the control group. Together, our results provide insights into the diverse functions of B7-H4 involved in the pathogenesis, recurrence and anti-tumor immunity of HCC, indicating B7-H4 as a novel and effective approach for future treatment strategies that benefits anticancer therapy., Competing Interests: CONFLICTS OF INTEREST The authors declare no conflict of interest.

Background: Previous studies have revealed that hepatitis B core antibody (anti-HBc) levels vary throughout the different phases of treatment-naïve chronic hepatitis B (CHB) patients and can be used as a predictor of treatment response in both interferon-α and nucleoside analogue therapies. However, few data have been published regarding the relationship between quantitative anti-HBc (qAnti-HBc) levels and liver fibrosis in patients with CHB., Results: A total of 489 HBeAg-positive (HBeAg (+)) and 135 HBeAg-negative (HBeAg (-)) patients were recruited. In both HBeAg (+) and HBeAg (-) groups, the S0-1/S0 subjects had significantly lower qAnti-HBc levels than the S2-4 subjects (p < 0.05). Multiple logistic regression analysis showed that the parameters for predicting significant fibrosis (S ≥ 2) included age, PLT and qAnti-HBc. In HBeAg (+) subjects, the AUROC of qAnti-HBc for predicting significant fibrosis was 0.734 (95% CI 0.689 to 0.778) and the optimal cut-off was 4.58 log10IU/mL, with a sensitivity of 63.08% and a specificity of 74.83%. In HBeAg (-) subjects, the AUROC was 0.707 (95% CI 0.612 to 0.801) and the optimal cut-off value was 4.37 log10IU/mL, with a sensitivity of 75.53% and a specificity of 56.10%., Materials and Methods: From 2012 to 2015, we conducted a cross-sectional study of treatment-naïve CHB patients. Liver biochemistry, hepatitis B virus (HBV) serological markers, HBV DNA, hepatitis B surface antigen (HBsAg) titers and HBV genotype were determined using commercial assays, and serum qAnti-HBc levels were measured using double-sandwich immunoassay. Liver biopsies and serum samples were obtained on the same day., Conclusions: The present study showed an association between high serum qAnti-HBc levels and significant fibrosis (S ≥ 2) in treatment-naïve CHB patients. Furthermore, we described a serum qAnti-HBc cut-off for predicting significant fibrosis in CHB patients infected with HBV genotype B or C.

Combination therapy comprising pegylated interferon-alpha (PegIFNα) and ribavirin (RBV) has been the standard of care for the chronic hepatitis C patients for more than a decade. Recently, direct antiviral agents show better efficacy, tolerance, and shorter treatment duration. However, the prohibitive costs of the regimens limit their use in developing countries where most of the HCV infection exists. Optimizing the treatment and understanding the host- and virus-factors associated with viral clearance were necessary for individualizing therapy to maximize sustained virologic response. To explore individualized antiviral strategies with PegIFNα-2a/IFNα-2b plus ribavirin for CHC patients, and to clarify predictive factors for virological response. A cohort of 314 patients were included in this open-label, prospective clinical trial, which received individualized doses of PegIFNα-2a or IFNα-2b combined with RBV according to body weight, disease status and complications, with the duration of 44 weeks after HCV RNA undetectable. All the IL-28B (rs8099917), IL-17A (rs8193036), IL-17B (rs2275913) and PD-1.1 SNPs were genotyped using the TaqMan system. The sustained virological response (SVR) in PegIFNα-2a group was significantly higher than that in IFNα-2b (85.8% vs 75.0%, P = 0.034), especially in HCV genotype 1 (84.0% vs 64.3%, P = 0.022). However, no significant differences were found in rapid virological response (RVR), complete early virological response (cEVR) and SVR between PegIFNα-2a and IFNα-2b according to different doses, respectively. The genotype frequency of IL-28B TT in patients with cEVR, SVR was higher than that in non-responsed patients (93.8% vs 78.1%, χ(2) = 7.827, P = 0.005; 95.9% vs 80.4%, χ(2) = 9.394, P = 0.002). No significant correlation between the genotype distribution of IL-17A, IL-17B and PD-1.1 with virological response. Individualized regimens of PegIFNα-2a/RBV and IFNα-2b/RBV could achieve satisfied virological response in Chinese HCV patients. The IL-28B (rs8099917) TT genotype is a clinical usefully marker for cEVR and SVR.

B7 family members are aberrantly expressed on the human hepatocellular carcinoma (HCC) cell surface, and induce local and systemic immunosuppression. Tumor-associated macrophages (TAMs) are a significant immune cell subpopulation in HCC and may be induced to express co-inhibitory molecules including B7 homologue 3 (B7-H3). In the present study, 79.3% of the HCC tissue samples showed high expression of B7-H3 which was positively correlated with the number of TAMs in the evaluated cancer tissues. Furthermore, high levels of TAMs or B7-H3 were associated with a shorter survival time of the HCC patients. In vitro, B7-H3 expression was upregulated at both the mRNA and protein levels in phorbol 12-myristate 13-acetate (PMA)-induced THP-1 cells cocultured with HepG2 cells in a Transwell system. In addition, B7-H3 promoted PMA-induced THP-1 cells to differentiate into the M2 phenotype, with evidence of increases in arginase 1 (Arg1), vascular endothelial cell growth factor (VEGF) and macrophage-derived chemokine (CCL22) mRNA following coculture with HepG2 cells. However, this phenomenon was abrogated through knockdown of B7-H3 by RNA interference or by blocking the signal transducer and activator of trans-cription 3 (STAT3) signaling pathway. Overall, these results suggest that the B7-H3-mediated STAT3 signaling pathway is an important mechanism for inducing M2-type polarization of TAMs, which accelerates HCC development. Our findings may support the development of novel therapeutic strategies for HCC patients through the skewing of the TAM phenotype by targeting the B7-H3 signaling pathway.

Background: Cytokines are crucial factors in the non-cytolytic antiviral process to inhibit HBV gene expression and replication. Interleukin (IL)-21 has been suggested to play an important role in HBV infection, but it remains unknown whether IL-21 can inhibit HBV replication or how it inhibits HBV replication., Methods: In this study, we investigated the influence of IL-21 on HBV replication based on human hepatoma Huh7.93 cells co-cultured with human peripheral blood mononuclear cells (PBMCs) and the possible correlation among IL-21, interferon-γ, tumour necrosis factor-α and IL-10., Results: We demonstrated that the decrease of IL-21 expression and the increase of IL-10 expression in PBMCs could promote HBV replication in vitro. We further revealed that IL-21 is not only able to effectively suppress HBV replication directly but also reduce HBV replication by inhibition of IL-10 secretion., Conclusions: Our results provide important evidence for the non-cytolytic antiviral mechanism mediated by cytokines and their interactions in chronic hepatitis B.

Aim: To construct a tricistronic hepatitis C virus (HCV) replicon with double internal ribosome entry sites (IRESes) of only 22 nucleotides for each, substituting the encephalomyocarditis virus (EMCV) IRESes, which are most often used as the translation initiation element to form HCV replicons., Methods: The alternative 22-nucleotide IRES, RNA-binding motif protein 3 IRES (Rbm3 IRES), was used to form a tricistronic HCV replicon, to facilitate constructing HCV-harboring stable cell lines and successive antiviral screening using a luciferase marker. Briefly, two sequential Rbm3 IRESes were inserted into bicistronic pUC19-HCV plasmid, consequently forming a tricistronic HCV replicon (pHCV-rep-NeoR-hRluc), initiating the translation of humanized Renilla luciferase and HCV non-structural gene, along with HCV authentic IRES initiating the translation of neomycin resistance gene. The sH7 cell lines, in which the novel replicon RNA stably replicated, were constructed by neomycin and luciferase activity screening. The intracellular HCV replicon RNA, expression of inserted foreign genes and HCV non-structural gene, as well as response to anti-HCV agents, were measured in sH7 cells and cells transiently transfected with tricistronic replicon RNA., Results: The intracellular HCV replicon RNA and expression of inserted foreign genes and HCV non-structural gene in sH7 cells and cells transiently transfected with tricistronic replicon RNA were comparable to those in cells stably or transiently transfected with traditional bicistronic HCV replicons. The average relative light unit in pHCV-rep-NeoR-hRluc group was approximately 2-fold of those in the pUC19-HCV-hRLuc and Tri-JFH1 groups (1.049 × 10(8) ± 2.747 × 10(7) vs 5.368 × 10(7) ± 1.016 × 10(7), P < 0.05; 1.049 × 10(8) ± 2.747 × 10(7) vs 5.243 × 10(7) ± 1.194 × 10(7), P < 0.05), suggesting that the translation initiation efficiency of the first Rbm3 IRES in the two sequential IRESes was stronger than the HCV authentic IRES and EMCV IRES. The fold changes of 72 h/4 h relative light units in the pHCV-rep-NeoR-hRluc and pUC19-HCV-hRLuc groups were similar (159.619 ± 9.083 vs 163.536 ± 24.031, P = 0.7707), and were both higher than the fold change in the Tri-JFH1 group 159.619± 9.083 vs 140.811 ± 9.882, P < 0.05; 163.536 ± 24.031 vs 140.811 ± 9.882, P < 0.05), suggesting that the replication potency of the Rbm3 IRES tricistronic replicon matched the replication of bicistronic replicon and exceeded the potency of EMCV IRES replicon. Replication of tricistronic replicons was suppressed by ribavirin, simvastatin, atorvastatin, telaprevir and boceprevir. Interferon-alpha 2b could not block replication of the novel replicon RNA in sH7 cells. After interferon stimulation, MxA mRNA and protein levels were lower in sH7 than in parental cells., Conclusion: Tricistronic HCV replicon with double Rbm3 IRESes could be applied to evaluate the replication inhibition efficacy of anti-HCV agents.