studies

704A AASLD ABSTRACTS HEPATOLOGY, October, 2015
the innate immune response following Poly(I:C) and HCV-RNA
transfection. LECT2 enhanced RIG-I-mediated IFNβ induction
and increased ISG induction through the activation of IRF3,
IRF7 and JAK/STAT pathway. To confirm the biologic significance
of these results, we generated LECT2 transgenic (Tg)
and knockout (KO) mice. LECT2-Tg mice showed increased ISG
induction following Poly(I:C) treatment in the liver. Conversely,
LECT2-KO mice showed impaired ISG induction following IFN
or Poly(I:C) treatment to 30–50% of that of WT mice. Conclusion:
Gene expression profiling of primary hepatocytes treated
with IFNα, IL28B, or both in combination revealed that LECT2,
which enhances the innate immune response and suppresses
HCV replication, was specifically induced by IL28B. LECT2
might participate in prolonged ISG induction by IL28B and in
the unique innate antiviral immune system of IL28B.
Disclosures:
Hikari Okada - Employment: Kanazawa University
Stanley M. Lemon - Advisory Committees or Review Panels: Merck, Santaris,
Abbott, Gilead; Consulting: Achillion, Idenix; Grant/Research Support: Merck,
Tibotec, Scynexis; Speaking and Teaching: Hoffman LaRoche
Shuichi Kaneko - Grant/Research Support: MDS, Co., Inc, Chugai Pharma., Co.,
Inc, Toray Co., Inc, Daiichi Sankyo., Co., Inc, Dainippon Sumitomo, Co., Inc,
Ajinomoto Co., Inc, Bristol Myers Squibb., Inc, Pfizer., Co., Inc, Astellas., Inc,
Takeda., Co., Inc, Otsuka„ÄÄPharmaceutical, Co., Inc, Eizai Co., Inc, Bayer
Japan, Eli lilly Japan
The following authors have nothing to disclose: Takayoshi Shirasaki, Masao
Honda, Tetsuro Shimakami, Kazuhisa Murai, Hirofumi Misu, Toshinari Takamura,
Seishi Murakami
1011
MicroRNA 17 Host Gene Protein and its targets PTEN
and NF-κB in Chronic Hepatitis C Virus Infection: Relation
to Hepatic inflammation, fibrosis and steatosis.
Hoda El Aggan 1 , Sahah A. Mahmoud 2 , Nevine M. El Deeb 3 ,
Ehab M. Hassona 1 , Sally El Demiry 1 ; 1 Department of Medicine
(Hepatobiliary Unit), Faculty of Medicine, University of Alexandria,
Alexandria, Egypt; 2 Department of Medical Biochemistry, Faculty
of Medicine, University of Alexandria, Alexandria, Egypt; 3 Department
of Pathology, Faculty of Medicine, University of Alexandria,
Alexandria, Egypt
Background/Aim: MicroRNAs (miRs) regulate post-transcriptional
gene expression in various biological processes. The
polycistronic miR-17~92 cluster is comprised of six miRs and
its primary transcript also encodes for a polypeptide of 70
amino acids designated as the miR-17 host gene (MIR17HG)
protein. The present study was designed to evaluate the plasma
levels of MIR17HG protein, an index of miR-17~92 cluster
activity, and hepatic expression of its targets phosphatase and
tensin homolog (PTEN) and nuclear factor kappa-B (NF-κB)
in patients with chronic hepatitis C virus (HCV) infection in
relation to hepatic steatosis, inflammation and fibrosis. Methods:
Thirty treatment-naïve patients with chronic HCV infection
[18 patients with chronic hepatitis C (CHC) and 12 patients
with cirrhosis] and 15 healthy subjects were included in the
study. Quantitative determination of plasma levels of MIR17HG
protein was performed using quantitative sandwich enzyme
immunoassay. Core liver biopsies obtained from patients with
chronic HCV infection were assessed for METAVIR histological
activity grade and fibrosis stage and steatosis grade. Immunohistochemical
staining of liver specimens was done using
monoclonal antibody against PTEN and NF-κB. Results: Plasma
MIR17HG protein levels showed a significant increase in
patients with chronic HCV infection compared with healthy subjects
(P = 0.012) and in patients with cirrhosis compared with
patients with CHC (P < 0.001). By plotting a receiver-operating
characteristic curve, the sensitivity and specificity of plasma
MIR17HG protein levels in discriminating patients with cirrhosis
from patients with CHC were 100% and 88.9% respectively
at a cut-off level of 45.5 pg/ml (AUC = 0.995). The plasma
MIR17HG protein levels were inversely correlated with hepatic
PTEN expression and positively correlated with serum levels of
aminotransferases, METAVIR histological activity grade and
fibrosis stage, steatosis grade and hepatic NF-κB expression
(P < 0.05). The hepatic PTEN expression showed positive correlations
with serum gamma glutamyl transpeptidase levels,
METAVIR fibrosis stage and steatosis grade (P < 0.05) and an
inverse correlation with hepatic NF-κB expression (P = 0.006).
Conclusion: Activation of the miR-17~92 cluster may play an
important role in the pathogenesis of HCV-related liver injury
via PTEN inhibition and NF-κB activation and could be a possible
therapeutic option in chronic HCV infection. Circulating
MIR17HG protein could be a useful biomarker for disease
progression.
Disclosures:
The following authors have nothing to disclose: Hoda El Aggan, Sahah A. Mahmoud,
Nevine M. El Deeb, Ehab M. Hassona, Sally El Demiry
1012
The FGL2:FcγRIIB Immunosuppressive Pathway Inhibits
HCV Specific Antiviral T Cell Responses in Chronic Infection
Ramzi Khattar, Kaveh Farrokhi, Hassan Sadozai, Vanessa Rojas
Luengas, Gary Levy, Nazia Selzner; University Health Network,
Toronto, ON, Canada
Background and Aims: Hepatitis C virus (HCV) evades immune
detection by limiting the magnitude and responsiveness of antiviral
T cells. FGL2 is a potent immunosuppressive effector molecule
of CD4 + CD25 + TIGIT + FOXP3 + Treg that exerts its activity
by binding to the inhibitory FCγRIIB receptor expressed on antigen
presenting cells. Binding of FGL2 to the FCγRIIB receptor
inhibits the maturation of dendritic cells, limiting responsiveness
of antiviral T cells. We examined the relationship between
FGL2 and HCV specific T cell responses in a cohort of HCV
patients. The study also examined the efficacy of a novel neutralizing
antibody towards FGL2 to restore HCV specific T cell
proliferation in vitro from HCV patients. Methods: 61 patients
with chronic HCV infection, 15 SVR and 8 healthy controls
were recruited to the study. TIGIT expression on CD4+CD25+-
FOXP3+ Treg and FGL2 production by T cells, dendritic cells
and macrophages was measured in patient PBMC by flow
cytometry. FGL2 levels were measured in patient samples by
ELISA and T cell reactivity to HCV by ex vivo peptide re-stimulation
using genotype specific HCV peptide arrays. Results: In
patients chronically infected with HCV, there was a significant
increase in frequency of CD4 + CD25 + FOXP3 + TIGIT + Treg cells
(42.5±4.1) compared to SVR patients (30.1±2.8) or healthy
controls (14.5±1.5) (P