Qing-Lei Zeng

Myeloid-derived suppressor cells are associated with viral persistence and downregulation of TCR ζ chain expression on CD8(+) T cells in chronic hepatitis C patients.

Myeloid-derived suppressor cells (MDSCs) play an important role in impairing the function of T cells. We characterized MDSCs in two chronic hepatitis C (CHC) cohorts: a cross-sectional group that included 61 treatment-naive patients with CHC, 14 rapid virologic response (RVR) cases and 22 early virologic response (EVR) cases; and a longitudinal group of 13 cases of RVR and 10 cases of EVR after pegylated-interferon-α/ribavirin treatment for genotype 1b HCV infection. Liver samples from 32 CHC patients and six healthy controls were subjected to immunohistochemical analysis. MDSCs frequency in treatment-naive CHC was significantly higher than in RVR, EVR, or healthy subjects and was positively correlated with HCV RNA. Patients infected with HCV genotype 2a had a significantly higher frequency of MDSCs than those infected with genotype 1b. Decreased T cell receptor (TCR) ζ expression on CD8+ T cells was significantly associated with an increased frequency of MDSCs in treatment-naive CHC patients and was restored by L-arginine treatment in vitro. Increased numbers of liver arginase-1+ cells were closely associated with the histological activity index in CHC. The TCR ζ chain was significantly downregulated on hepatic CD8+ T cells in CHC. During antiviral follow up, MDSCs frequency in peripheral blood mononuclear cells was directly correlated with the HCV RNA load in the plasma and inversely correlated with TCR ζ chain expression in CD8+ T cells in both RVR and EVR cases. Notably, the RVR group had a higher frequency of MDSCs at baseline than the EVR group. Collectively, this study provides evidence that MDSCs might be associated with HCV persistence and downregulation of CD8 ζ chain expression.

Sofosbuvir and ABT-450: Terminator of hepatitis C virus?

Combination therapy with peginterferon (pegIFN)-α and ribavirin (RBV) has been the standard of care (SOC) for chronic hepatitis C. Unfortunately, not all patients can achieve a sustained virologic response (SVR) with this regimen. SVR rates are approximately 80% in patients with hepatitis C virus (HCV) genotype 2, 3, 5 and 6 and 40%-50% in patients with genotype 1 and 4. Therefore, strategies to improve SVR rates have been an important issue for clinical physicians. Several direct acting antiviral agents (DAAs) have significantly higher SVR rates when combined with pegIFN-α and RBV than pegIFN-α and RBV alone. Treatments containing DAAs have several advantages over the previous SOC, including higher specificity and efficacy, shorter treatment durations, fewer side effects, and oral administration. Based on these advantages, treatment with pegIFN-α and RBV plus telaprevir or boceprevir has become the current SOC for patients with genotype 1 HCV infection. However, many patients are either not eligible for therapy or decline treatment due to coexisting relative or absolute contraindications as well as an inability to tolerate the hematological side effects and adverse events caused by the new SOC. These factors have contributed to the advent of pegIFN-α-free regimens. The newest therapeutic regimens containing sofosbuvir and ABT-450 have shown promising results. In this review, we summarize the development of anti-HCV agents and the clinical efficacy of sofosbuvir and ABT-450-based therapies as well as the potential for future HCV studies.

HCV-specific interleukin-21+CD4+ T cells responses associated with viral control through the modulation of HCV-specific CD8+ T cells function in chronic hepatitis C patients

Interleukin-21 (IL-21)+CD4+ T cells are involved in the immune response against hepatitis B virus (HBV) by secreting IL-21. However, the role of IL-21+CD4+ T cells in the immune response against chronic hepatitis C (CHC) virus infection is poorly understood. This study aimed to investigate the role of IL-21+CD4+ T cells in CHC patients and the potential mechanisms. The study subjects included nineteen CHC patients who were grouped by viral load (low, < 106 RNA copies/ml, n = 8; high, > 106 RNA copies/ml, n = 11). The peripheral frequency of HCV-specific IL-21+CD4+ T cells was higher in the low viral load group and was negatively correlated with the serum HCV RNA viral load in all CHC patients. Meanwhile, IL-21+ cells accumulated in the liver in the low viral load group. In vitro, IL-21 treatment increased the expression of proliferation markers and cytolytic molecules on HCV-specific CD8+ T cells. In summary, these findings suggest that HCV-specific IL-21+CD4+ T cells might contribute to HCV control by rescuing HCV-specific CD8+ T cells in CHC patients.

Primary biliary cirrhosis-associated hepatocellular carcinoma in Chinese patients: Incidence and risk factors

AIM To investigate the incidence, characteristics, and risk factors for hepatocellular carcinoma (HCC) in Chinese patients with primary biliary cirrhosis (PBC). METHODS We reviewed the data of 52 PBC-associated HCC patients treated at Beijing 302 Hospital from January 2002 to December 2013 and analyzed its incidence and characteristics between the two genders. The risk factors for PBC-associated HCC were analyzed via a case-control study comprising 20 PBC patients with HCC and 77 matched controls without HCC. The matched factors included gender, age, follow-up period and Child-Pugh scores. Conditional logistic regression was used to evaluate the odds ratios of potential risk factors for HCC development. A P < 0.05 was considered statistically significant. RESULTS The incidence of HCC in Chinese PBC patients was 4.13% (52/1255) and was significantly higher in the males (9.52%) than in the females (3.31%). Among the 52 PBC patients with HCC, 55.76% (29/52) were diagnosed with HCC and PBC simultaneously, and 5.76% (3/52) were diagnosed with HCC before PBC. The males with PBC-associated HCC were more likely than the females to have undergone blood transfusion (18.75% vs 8.33%, P = 0.043), consumed alcohol (31.25% vs 8.33%, P = 0.010), smoked (31.25% vs 8.33%, P = 0.010), had a family history of malignancy (25% vs 5.56%, P = 0.012), and had serious liver inflammation, as indicated by the elevated levels of alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase, and γ-glutamyl transpeptidase (P < 0.05). Conditional logistic regression analysis revealed that body mass index (BMI) ≥ 25 [adjusted odds ratio (AOR) = 1.116, 95%CI: 1.002-1.244, P = 0.045] and history of alcohol intake (AOR = 10.294, 95%CI: 1.108-95.680, P = 0.040) were significantly associated with increased odds of HCC development in PBC patients. CONCLUSION HCC is not rare in Chinese PBC patients. Risk factors for PBC-associated HCC include BMI ≥ 25 and a history of alcohol intake. In addition to regular monitoring, PBC patients may benefit from abstinence from alcohol and body weight control.

Interleukin-21 mediates hepatitis B virus-associated liver cirrhosis by activating hepatic stellate cells.

Interleukin‐21 (IL‐21) is involved in effective primary hepatic immune response against hepatitis B virus (HBV) and profibrotic function. However, the role of IL‐21 in HBV‐associated liver cirrhosis is poorly understood. This study aimed to investigate the role of IL‐21 in HBV‐associated liver cirrhosis and possible mechanisms.

Upregulation of OX40 ligand on monocytes contributes to early virological control in patients with chronic hepatitis C

Dysfunctional hepatitis C virus (HCV) specific CD4+ T cells are known to contribute to inadequate adaptive immunity in chronic hepatitis C (CHC), although the underlying mechanisms remain largely undefined. In this study, OX40 ligand (OX40L) expression was investigated in 41 treatment‐naïve CHC patients, 20 sustained virological responders and 36 healthy subjects. We observed that OX40L expression was significantly upregulated in peripheral monocytes in CHC patients compared with sustained virological responders and healthy subjects. OX40L upregulation correlated significantly with plasma viral load rather than serum alanine aminotransaminase levels. Furthermore, longitudinal analyses indicated that upregulated OX40L expression on monocytes is closely associated with rapid or early virological responses in patients receiving pegylated IFN‐α/ribavirin treatment. In vitro, HCV core antigen strongly stimulated monocyte expression of OX40L and blockade of TLR2 signaling significantly downregulated OX40L expression. More importantly, elevated OX40L expression was also shown to be closely associated with elevation of the HCV‐specific CD4+ T‐cell response and in vitro blockade of OX40L expressed on monocytes led to impaired CD4+ T‐cell function. These findings, therefore, implicate OX40L expression can be used as a marker to evaluate antiviral treatment efficacy and extend the notion that enhancement of OX40L expression could be a good way for immunotherapy in CHC patients.

Risk factors for liver-related mortality in chronic hepatitis C patients: A deceased case-living control study

AIM To investigate the risk factors for liver-related mortality in chronic hepatitis C (CHC) patients. METHODS All deceased CHC inpatient data were collected from the Beijing 302 Hospital clinical database, which includes more than 8250 CHC inpatients during the period from 2002 to 2012. The controls were matched to cases by age (± 2 years), sex and date of hospital admission (within the same year). Potential risk factors were included for the evaluation, and odds ratios (OR) and 95%CI were estimated using univariate (unadjusted) and multivariate (adjusted OR, AOR) conditional logistic regression. All statistical tests were two-sided. P values < 0.05 were considered statistically significant. RESULTS Based on examinations of 144 CHC-related deceased cases and 576 controls, we found that antiviral therapy with interferon-α was associated with a 47% decrease in the risk of hepatic mortality (AOR = 0.53, 95%CI: 0.28-0.99, P = 0.048). Additionally, the initial diagnostic stage of the disease (AOR = 2.89, 95%CI: 1.83-4.56 and P < 0.001 for liver cirrhosis/AOR = 8.82, 95%CI: 3.99-19.53 and P < 0.001 for HCC compared with CHC), diabetes (AOR = 2.35, 95%CI: 1.40-3.95, P = 0.001), hypertension (AOR = 1.76, 95%CI: 1.09-2.82, P = 0.020), alcohol consumption (AOR = 1.73, 95%CI: 1.03-2.81, P = 0.037) and HBsAg positivity (AOR = 22.28, 95%CI: 5.58-89.07, P < 0.001) were associated with a significant increase in the risk of liver-related mortality in CHC patients. CONCLUSION This study indicates that interferon-α treatment, the stage at the initial diagnosis of the disease and comorbidities are all independent risk factors for liver-related mortality in CHC patients.

LINE-1 ORF-1p enhances the transcription factor activity of pregnenolone X receptor and promotes sorafenib resistance in hepatocellular carcinoma cells

Background LINE-1 ORF-1p is encoded by the human pro-oncogene LINE-1. Our previous work showed that LINE-1 ORF-1p could enhance the resistance of hepatocellular carcinoma (HCC) cells to antitumor agents. However, the mechanisms involved in LINE-1 ORF-1p-mediated drug resistance remain largely unknown. Materials and methods The endogenous mRNA level of LINE-1 ORF-1p in clinical HCC specimens was examined using quantitative PCR (qPCR). The prognosis of HCC patients was assessed using time to progression and overall survival. The transcription factor activity of pregnenolone X receptor (PXR) was examined using luciferase gene reporter assays, qPCR, chromatin immunoprecipitation assays and cellular subfraction assays. Protein interaction between LINE-1 ORF-1p and PXR was detected by co-immunoprecipitation. The effect of LINE-1 ORF-1p on sorafenib resistance in HCC cells was studied using in vitro and in vivo models. Results A high level of LINE-1 ORF-1p in clinical specimens was related to poor prognosis in patients who received sorafenib treatment. LINE-1 ORF-1p increased the transcription factor activity of PXR by interacting with PXR and enhancing its cytoplasmic/nuclear translocation, and recruiting PXR to its downstream gene promoter, in turn enhancing the expression of the sorafenib resistance-related genes, CYP3A4 and mdr-1. LINE-1 ORF-1p enhanced the resistance to and clearance of sorafenib in HCC cells. Conclusion LINE-1 ORF-1p enhances the transcription factor activation of PXR and promotes the clearance of and resistance to sorafenib in HCC cells.

Interleukin-21 mediates hepatitis B virus-associated liver cirrhosis by activating hepatic stellate cells

Interleukin‐21 (IL‐21) is involved in effective primary hepatic immune response against hepatitis B virus (HBV) and profibrotic function. However, the role of IL‐21 in HBV‐associated liver cirrhosis is poorly understood. This study aimed to investigate the role of IL‐21 in HBV‐associated liver cirrhosis and possible mechanisms.

Interleukin-21 mediates hepatitis B virus-associated liver cirrhosis by activating hepatic stellate cells: Interleukin-21 mediates liver cirrhosis

Interleukin‐21 (IL‐21) is involved in effective primary hepatic immune response against hepatitis B virus (HBV) and profibrotic function. However, the role of IL‐21 in HBV‐associated liver cirrhosis is poorly understood. This study aimed to investigate the role of IL‐21 in HBV‐associated liver cirrhosis and possible mechanisms.