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1.  Impact of oral silymarin on virus- and non-virus-specific T-cells responses in chronic hepatitis C infection 
Journal of viral hepatitis  2013;20(7):453-462.
Silymarin displays anti-inflammatory effects on T-lymphocytes in vitro. The immunomodulatory properties of oral silymarin in vivo in humans with chronic hepatitis C have not previously been characterized. We hypothesized that silymarin would suppress T-cell proliferation and pro-inflammatory cytokine production of virus- and non-virus-specific T-cells while increasing anti-inflammatory IL-10 production in vivo. Patients from one site of the SyNCH-HCV double-masked, placebo-controlled study of oral silymarin in prior interferon non-responders with chronic hepatitis C provided blood samples at baseline and treatment week 20. Mononuclear cells were stimulated with recombinant HCV proteins and controls in 3H-thymidine proliferation assays, IFNγ Elispot and IL-10 Elispot. The frequency of CD4+CD25hi and CD4+foxp3+ regulatory T-cells, serum cytokine levels, serum IP-10 and lymphocyte interferon-stimulated gene expression were also quantified at baseline and week 20. Thirty-two patients were recruited (10; placebo, 11; 420mg three times a day, 11; 700mg three times a day). Serum ALT and HCV RNA titers did not change in any group. HCV-specific CD4+ T-cell proliferation and the frequency of IFNγ– and IL-10-producing T-cells were not significantly changed in silymarin-treated subjects. However, C. albicans-induced T-cell IFNγ and phytohemagglutinin-induced T-cell proliferation were suppressed by silymarin therapy. A trend towards augmentation of interferon-induced ISG15 expression was present in the high-dose silymarin group. While no effect on HCV-specific T-cells was identified, these data confirm that high-dose oral silymarin exerts modest non-specific immunomodulatory effects in vivo. The impact of this anti-inflammatory effect on long-term liver health in chronic hepatitis C merits future clinical investigation.
PMCID: PMC3675799  PMID: 23730838
silymarin; T-cell; lymphocyte; hepatitis C; interferon-gamma; interferon-stimulated gene
2.  Do statins reduce hepatitis C RNA titers during routine clinical use? 
AIM: To compare hepatitis C virus (HCV) titers in patients with chronic hepatitis C with and without exposure to 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (statins).
METHODS: Medical records were reviewed for 6463 patients with documented HCV infection at a single center between March 2004 and September 2006. Patients with confirmed viremia and meeting inclusion criteria were assigned to one of three groups: Group A (n = 50), dyslipidemic patients with statin usage during HCV RNA polymerase chain reaction (PCR) determination; Group B (n = 49), dyslipidemic patients with prior or future statin usage but not at the time of HCV RNA PCR determination; and Group C (n = 102), patients without statin usage during the study period. The primary analysis explored the effect of statin therapy on HCV viremia. Secondary analyses assessed class effect, dose response, and effect of other lipid-lowering therapies on HCV viral titers.
RESULTS: Median HCV RNA titers did not significantly differ among the three groups (Group A: 4 550 000 IU/mL, Group B: 2 850 000 IU/mL, Group C: 3 055 000 IU/mL). For those subjects with longitudinal assessment of HCV viremia prior to and while on statins, there were no significant differences between pre- and post-HCV viral titers. Additionally, no differences in HCV titers were observed at any dose level of the most prescribed statin, simvastatin. However, hypertriglyceridemia independently correlated with HCV titers, and niacin exposure was associated with significantly lower viral titers (P < 0.05).
CONCLUSION: There was no apparent effect of statins on HCV viral replication in this analysis. Further investigation is warranted to explore the possible antiviral properties of triglyceride-lowering agents and their potential role as adjuncts to standard HCV therapy.
PMCID: PMC2768880  PMID: 19859994
Hepatitis C; 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitor; Statins; Geranylgeranyl; Prenylation
4.  Dysfunctional B-cell activation in cirrhosis due to hepatitis C infection associated with disappearance of CD27+ B-cell population 
Hepatology (Baltimore, Md.)  2012;55(3):709-719.
Chronic hepatitis C virus infection is a leading cause of cirrhosis and hepatocellular carcinoma. Both advanced solid tumors and hepatitis C have previously been associated with memory B-cell dysfunction. In this study we sought to dissect the impact of viral infection, cirrhosis and liver cancer on memory B-cell frequency and function in the spectrum of HCV disease.
Peripheral blood from healthy donors, HCV-infected patients with F1–F2 liver fibrosis, HCV-infected patients with cirrhosis, patients with HCV-related hepatocellular carcinoma and non-HCV-infected cirrhotics were assessed for B-cell phenotype by flow cytometry. Isolated B-cells were stimulated with anti-CD40 antibodies and TLR9 agonist for assessment of costimulation marker expression, cytokine production, immunoglobulin production and CD4+ T-cell allostimulatory capacity.
CD27+ memory B-cells, and more specifically CD27+IgM+ B-cells, were markedly less frequent in cirrhotic patients independent of HCV infection. Circulating B-cells in cirrhotics were hyporesponsive to CD40/TLR9 activation as characterized by CD70 upregulation, TNFβ secretion, IgG production and T-cell allostimulation. Lastly, blockade of TLR4 and TLR9 signaling abrogated the activation of normal donor B-cells by cirrhotic plasma suggesting a role for bacterial translocation in driving B-cell changes in cirrhosis.
Profound abnormalities in B-cell phenotype and function occur in cirrhosis independent of hepatitis C viral infection. These B-cell defects may explain in part the vaccine hyporesponsiveness and susceptibility to bacterial infection in this population.
PMCID: PMC3245804  PMID: 21932384
hepatitis C; cirrhosis; hepatocellular carcinoma; human; B-cell; CD27; CD40; sCD14; TLR4; TLR9; bacterial translocation
5.  Relationship between adherence to hepatitis C virus therapy and virologic outcomes: a cohort study 
Annals of Internal Medicine  2011;155(6):353-360.
Adherence to hepatitis C virus (HCV) therapy with pegylated interferon and ribavirin has been incompletely examined.
To evaluate the relationship between adherence to HCV therapy and early and sustained virologic response, assess changes in adherence over time, and examine risk factors for non-adherence.
Retrospective cohort study.
National Veterans Affairs Hepatitis C Clinical Case Registry
5,706 HCV-infected patients (genotypes 1, 2, 3, or 4) with at least one prescription for pegylated interferon and ribavirin between 2003 and 2006 and HCV RNA results prior to and after treatment initiation.
Adherence was calculated over 12-week intervals using pharmacy refill data. Endpoints included early virologic response (decrease of ≥2 log10 HCV RNA at 12 weeks) and sustained virologic response (undetectable HCV RNA 24 weeks after end of treatment).
Early virologic response increased with higher levels of ribavirin adherence over the initial 12 weeks of therapy (genotype 1, 4: 25/68 [37%] with the lowest category [≤40% adherence] versus 1,367/2,187 [63%] with the highest category [91–100% adherence], p<0.001; genotype 2, 3: 12/18 [67%] with ≤40% adherence versus 651/713 [91%] with 91–100% adherence, p<0.001). Among genotype 1 and 4 patients, sustained response increased with higher ribavirin adherence over the second, third, and fourth 12-week intervals. Results were similar for interferon adherence. Mean adherence to interferon and ribavirin decreased 3.4% and 6.6% per 12-week interval, respectively (test for trend, p<0.001 for each drug). Patients prescribed growth factors or thyroid medications during treatment had higher mean antiviral adherence.
Observational study without standardized timing for outcomes measurements.
Early and sustained virologic responses increased with higher levels of adherence to interferon and ribavirin. Adherence to both antivirals declined over time, but more so for ribavirin.
PMCID: PMC3366635  PMID: 21930852
Adherence; hepatitis C virus; HCV; antiviral therapy
6.  Adherence to Hepatitis C Virus Therapy in HIV/Hepatitis C-Coinfected Patients 
AIDS and behavior  2013;17(1):94-103.
Adherence to hepatitis C virus (HCV) therapy has been incompletely examined among HIV-infected patients. We assessed changes in interferon and ribavirin adherence and evaluated the relationship between adherence and early (EVR) and sustained virologic response (SVR). We performed a cohort study among 333 HIV/HCV-coinfected patients who received pegylated interferon and ribavirin between 2001 and 2006 and had HCV RNA before and after treatment. Adherence was calculated over 12-week intervals using pharmacy refills. Mean interferon and ribavirin adherence declined 2.5 and 4.1 percentage points per 12-week interval, respectively. Among genotype 1/4 patients, EVR increased with higher ribavirin adherence, but this association was less strong for interferon. SVR among these patients was higher with increasing interferon and ribavirin adherence over the first, second, and third, but not fourth, 12-week intervals. Among HIV/HCV patients, EVR and SVR increased with higher interferon and ribavirin adherence. Adherence to both antivirals declined over time, but more so for ribavirin.
PMCID: PMC3514597  PMID: 22907288
Adherence; hepatitis C virus; HIV; antiviral therapy; pegylated interferon; ribavirin
7.  Human Hepatocellular Carcinoma Metabolism: Imaging by Hyperpolarized 13C Magnetic Resonance Spectroscopy 
Journal of liver: disease & transplantation  2012;1(1):10.4172/2325-9612.1000101.
Most cancers exhibit high levels of aerobic glycolytic metabolism with diminished levels of mitochondrial oxidative phosphorylation even in the presence of normal or near-normal levels of oxygen (“Warburg effect”). However, technical challenges have limited the development of non-invasive in vivo imaging techniques for monitoring glycolytic metabolism of hepatocellular carcinoma (HCC) and quantitatively evaluating the impact of this effect on the growth and therapy of this disease. Thus, there is a critical need to develop non-invasive techniques for longitudinal assessment of the metabolism and treatment response of patients with unresectable HCCs.
This article discusses a novel method, “Hyperpolarized 13C MRS imaging”, for achieving this objective and thus improving the prognosis of HCC patients. The primary objective has been to characterize in vivo metabolic biomarkers as determinants of HCC metabolism and treatment response of unresectable HCC tumors or viable HCC cells.
This innovative technique capitalizes on a new technology that increases the sensitivity of MRS detection of crucial metabolites in cancer cells.
It is anticipated that this innovative approach will lead to improved methods, both for the diagnosis and staging of HCCs and for the facilitation of the development of enzyme targeted therapies and other therapeutic interventions.
PMCID: PMC3820166  PMID: 24224182
Hepatocellular Carcinoma; “Warburg effect”; Hyperpolarized 13C MRS; [1-13C] pyruvate; Alanine Transaminase; Branched-Chain Aminotransferases
8.  Evaluation of the Significance of Pretreatment Liver Biopsy and Baseline Mental Health Disorder Diagnosis on Hepatitis C Treatment Completion Rates at a Veterans Affairs Medical Center 
Objectives. This study was performed to define the overall treatment response rates and treatment completion rates among the population of Hepatitis C infected patients at an urban VA Medical Center. Additionally, we examined whether pretreatment liver biopsy is a positive predictor for treatment completion and if the presence of mental health disorders is a negative predictor for treatment completion. Methods. Retrospective chart review was performed on the 375 patients that were treated for HCV and met the study inclusion parameters between January 1, 2003 and April 1, 2008 at our institution. Clinical data was obtained from the computerized patient record system and was analyzed for respective parameters. Results. Sustained virological response was achieved in 116 (31%) patients. 169 (45%) patients completed a full treatment course. Also, 44% of patients who received a pre-treatment liver biopsy completed treatment versus 46% completion rates for patients who did not receive a pretreatment liver biopsy. Baseline ICD9 diagnosis of a mental health disorder was not associated with higher treatment discontinuation rates. Conclusions. In conclusion, pretreatment liver biopsy was not a positive predictor for treatment completion, and the presence of mental health disorders was not a negative predictor for treatment completion.
PMCID: PMC3670541  PMID: 23762548
9.  Peripheral virus-specific T-cell Interleukin-10 responses develop early in acute hepatitis C infection and become dominant in chronic hepatitis 
Journal of hepatology  2008;48(6):903-913.
Background & Aims
Interleukin-10 (IL-10) has been ascribed pro-viral but anti-fibrotic properties in chronic hepatitis C virus (HCV) infection. In this study, we examined the role of HCV-specific T-cell IL-10 response in patients with acute and chronic HCV infection.
Peripheral HCV-specific T-cell IL-10 and IFNγ responses were measured in cytokine Elispot assay using overlapping HCV-derived peptides in patients with chronic (n=61), resolved (n=15) and acute (n=8) hepatitis C, looking for their onset, quantity, breadth and durability relative to clinical and virological outcomes. The source and effect of HCV-specific IL-10 response were determined in depletion and IL-10 neutralization experiments.
Both HCV-specific IL-10 and IFNγ responses were detected early within 1–2 months of acute clinical hepatitis C. However, only HCV-specific IL-10 response correlated with elevated liver enzymes, increased viremia and suppressed HCV-specific CD4+ T-cell proliferation in acute infection. While these associations were lost in established chronic infection, HCV-specific IL-10 responses were increased in patients without cirrhosis while IL-10 blockade enhanced antiviral effector IFNγ responses.
HCV-specific IL-10 Tr1 responses may play a dual role in HCV infection, dampening effector T-cells to promote viral persistence in acute infection but also protecting against progressive fibrosis in chronic infection.
PMCID: PMC2430081  PMID: 18384906
hepatitis C; interleukin-10; interferon-gamma; regulatory T-cells; CD8+ T-cells; IL-10; HCV
10.  Validation of glypican-3-specific scFv isolated from paired display/secretory yeast display library 
BMC Biotechnology  2012;12:23.
Glypican-3 (GPC3) is a heparan-sulfate proteoglycan frequently expressed on the cell membrane of malignant hepatocytes in hepatocellular carcinoma. The capacity for screening potential antibodies in vitro using human hepatocellular lines is critical to ensure binding to this highly post-translationally modified glycophosphatidylinositiol-linked protein. We hypothesized that we could utilize a recently described paired display/secretory yeast library to isolate human-derived scFv against glypican-3 for potential diagnostic and/or therapeutic application.
Using two different biotinylated antigen targets, a synthesized 29mer fragment GPC3550-558 and a truncated GPC3368-548 fused with glutathione S-transferase (GST) we enriched the yeast display library to greater than 30% target-specific yeast with both positive selection and depletion of streptavidin- and GST-specific clones. After cloning of scFv cDNA from the enriched sub-library, scFv specificity was validated by ELISA for binding to recombinant protein from prokaryotic and eukaryotic sources and ultimately naturally presented human protein on the cell membrane of human hepatocellular cell lines. Specificity was confirmed using non-expressing cell lines and shRNA knockdown. Ultimately, five unique scFv with affinity EC50 ranging from 5.0-110.9nM were identified.
Using a paired display/secretory yeast library, five novel and unique scFvs for potential humoral or chimeric therapeutic development in human hepatocellular carcinoma were isolated and characterized.
PMCID: PMC3425314  PMID: 22564378
11.  Collapse of the CD27+ B cell compartment associated with systemic plasmacytosis in patients with advanced melanoma and other cancers 
Disturbed peripheral blood B cell homeostasis complicates certain infections and autoimmune diseases, such as HIV and systemic lupus erythematosus, but has not been reported in cancer. This study aimed to investigate whether B cell physiology was altered in the presence of melanoma and other cancers.
Experimental Design
Flow cytometry was used to identify phenotypic differences in B cells from patients with melanoma and normal donors. In vitro stimulated B cells were assessed for responsiveness and also used as stimulators of allogeneic T cells in mixed lymphocyte reactions.
We demonstrate B cell dysregulation in patients with advanced melanoma (n=26) and other solid tumors (n=13), marked by a relative and absolute loss of CD27+ (memory) B cells and associated with an aberrant systemic plasmacytosis. Functionally, B cells from patients with melanoma inefficiently upregulated immunoregulatory molecules and weakly secreted cytokines in response to CD40 and TLR9 agonists. Stimulated B cells from patients induced proliferation of alloreactive CD4+ T cells, but these T cells poorly secreted IFNγ and IL-2. These effects were recapitulated by using purified normal donor CD27neg B cells in these same assays, linking the predominance of CD27neg B cells in patients with the observed functional hyporesponsiveness. Indeed, B cell dysfunction in patients strongly correlated with the extent of loss of CD27+ B cells in peripheral blood.
Disturbed B cell homeostasis is a previously unrecognized feature of patients with advanced melanoma and other cancers and may represent an unanticipated mechanism of immune incompetence in cancer.
PMCID: PMC2896505  PMID: 19549767
cancer; melanoma; B cells; plasmacytosis; memory
12.  Human Leukocyte Antigen Class II Associations with Hepatitis C Virus Clearance and Virus-Specific CD4 T Cell Response Among Caucasians and African Americans 
Hepatology (Baltimore, Md.)  2008;48(1):70-79.
The outcome of hepatitis C virus (HCV) infection has been associated with antiviral CD4 T cell response, human leukocyte antigens (HLA) class II genotypes, and ethnicity. However, HLA class II molecules restrict the nature of CD4 T cell response, and HLA distributions differ between ethnic groups. In this study, we asked whether HLA class II genotypes associated with HCV clearance are shared between Caucasian and African Americans and whether they contribute to enhanced antiviral CD4 T cell response. In a cohort of 93 HCV-seropositive subjects from Northeast America with defined ethnicity, virological outcome, and HCV-specific CD4 T cell proliferation, we confirm the previously reported associations between HCV clearance and two HLA types (DQB1*03, DRB1*11) while identifying a new association with DRB3*02. Strikingly, these associations were identified only among Caucasian [DQB1*03: odds ratio (OR), 10.4; P = 0.031, DRB1*11: OR, 7.0, P = 0.019; DRB3*02: OR, 8.3, P = 0.005; DQB1*03-DRB3*02: OR, 13.5, P = 0.001) but not among African American patients. Furthermore, although HLA DQB1*03, DRB1*11, and DRB3*02 genotypes were associated with increased HCV-specific CD4 T cell response in univariate analyses, these associations were lost when controlling for virological outcomes.
We conclude that the immunogenetic basis for HCV clearance differs between ethnic groups and that the association between HLA class II and HCV clearance is not directly explained by antiviral CD4 T cell response.
PMCID: PMC2749605  PMID: 18537178
13.  Functional restoration of HCV-specific CD8 T-cells by PD1 blockade is defined by PD1 expression and compartmentalization 
Gastroenterology  2008;134(7):1927-1937.e2.
Background & Aims
The immuno-inhibitory receptor Programmed Death-1 (PD-1) is upregulated on dysfunctional virus-specific CD8 T-cells during chronic viral infections and blockade of PD-1:PD-ligand (PD-L) interactions can restore their function. As hepatitis C virus (HCV) persists in the liver with immune-mediated disease pathogenesis, we examined the role of PD1/PD-L pathway in antigen-specific CD8 T-cell dysfunction in the liver and blood of HCV-infected patients.
PD-1 expression and function of circulating CD8 T-cells specific for HCV, EBV and Flu were examined ex vivo and following antigenic stimulation in vitro in patients with acute, chronic and resolved HCV infection using class I tetramers and flow cytometry. Intrahepatic CD8 T-cells were examined from liver explants of chronically HCV-infected transplant recipients.
Intrahepatic HCV-specific CD8 T-cells from chronically HCV-infected patients were highly PD-1-positive, profoundly dysfunctional and unexpectedly refractory to PD-1:PD-L blockade, contrasting from circulating PD-1-intermediate HCV-specific CD8 T-cells with responsiveness to PD-1:PD-L blockade. This intrahepatic functional impairment was HCV-specific and directly associated with the level of PD-1 expression. Highly PD-1-positive intrahepatic CD8 T-cells were more phenotypically exhausted with increased cytotoxic T-lymphocyte antigen 4 (CTLA-4) and reduced CD28 and CD127 expression, suggesting that active antigen-specific stimulation in the liver induces a profound functional exhaustion not reversible by PD-1:PD-L blockade alone.
HCV-specific CD8 T-cell dysfunction and responsiveness to PD-1:PD-L blockade are defined by their PD-1 expression and compartmentalization. These findings provide new and clinically relevant insight to differential antigen-specific CD8 T-cell exhaustion and their functional restoration.
PMCID: PMC2665722  PMID: 18549878
Cellular immunity; immune exhaustion; immune tolerance; immune regulation; effector T-cell dysfunction; co-stimulation; PD-1; immunotherapy; viral pathogenesis; intrahepatic T-cell response; vaccine
14.  Strain-Specific T-Cell Suppression and Protective Immunity in Patients with Chronic Hepatitis C Virus Infection 
Journal of Virology  2005;79(11):6976-6983.
Hepatitis C virus (HCV) frequently persists with an apparently ineffective antiviral T-cell response. We hypothesized that some patients may be exposed to multiple HCV subtypes and that strain-specific T cells could contribute to the viral dynamics in this setting. To test this hypothesis, CD4 T-cell responses to three genotype 1a-derived HCV antigens and HCV antibody serotype were examined in chronically HCV infected (genotypes 1a, 1b, 2, 3, and 4) and spontaneously HCV recovered subjects. Consistent with multiple HCV exposure, 63% of patients infected with genotypes 2 to 4 (genotypes 2-4) and 36% of those infected with genotype 1b displayed CD4 T-cell responses to 1a-derived HCV antigens, while 29% of genotype 2-4-infected patients showed serotype responses to genotype 1. Detection of 1a-specific T cells in patients without active 1a infection suggested prior self-limited 1a infection with T-cell-mediated protection from 1a but not from non-1a viruses. Remarkably, CD4 T-cell responses to 1a-derived HCV antigens were weakest in patients with homologous 1a infection and greater in non-1a-infected patients: proportions of patients responding were 19% (1a), 36% (1b), and 63% (2-4) (P = 0.0006). Increased 1a-specific CD4 T-cell responsiveness in non-1a-infected patients was not due to increased immunogenicity or cross-reactivity of non-1a viruses but directly related to sequence divergence. We conclude that the T-cell response to the circulating virus is either suppressed or not induced in a strain-specific manner in chronically HCV infected patients and that, despite their ability to clear one HCV strain, patients may be reinfected with a heterologous strain that can then persist. These findings provide new insights into host-virus interactions in HCV infection that have implications for vaccine development.
PMCID: PMC1112102  PMID: 15890937

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