studies

702A AASLD ABSTRACTS HEPATOLOGY, October, 2015
1006
Type III interferon responses contribute to hepatitis virus
infection and depended on IFNL3-IFNL4 variant
Tsunamasa Watanabe 2,1 , Susumu Tsutsumi 2 , Kentaro Matsuura 3 ,
Etsuko Iio 3 , Noboru Shinkai 3 , Kayoko Matsunami 3 , Fumio Itoh 1 ,
Yasuhito Tanaka 2 ; 1 Department of Internal Medicine, Division of
Gastroenterology and Hepatology, St. Marianna University School
of Medicine, Kawasaki, Japan; 2 Department of Virology and Liver
Unit, Nagoya City University Graduate School of Medical Sciences,
Nagoya, Japan; 3 Department of Gastroenterology and
Metabolism, Nagoya City University Hospital, Nagoya, Japan
Introduction: Type III interferon, which consist of interferon-l
(IFNL)1, 2, 3, and 4, has received considerable attention in
hepatotropic hepatitis C virus (HCV), as many independent
genome-wide association studies have identified a strong association
between IFNL3-IFNL4 variants and outcome of HCV.
Materials and Methods: We employed an original primary
human hepatocytes (PHH) systems, isolated from chimeric
mice harboring human hepatocytes without cryopreservation,
to investigate innate immune responses against hepatotropic
viruses including mimic of HCV infections and hepatitis B virus
(HBV) infection. The antiviral effects of IFNL were also investigated
in vivo using chronically HCV-infected chimeric mice
transplanted with human hepatocytes of IFNL3-IFNL4 favorable
or unfavorable genotype. Results: In vivo study using pegylated
IFNL1 revealed that the initial viral decline of HCV-RNA by
IFNL1 was similar in both IFNL3-IFNL4 favorable and unfavorable
genotype. Compared to the effect of pegylated IFN-a,
however, the antiviral effects of IFNL was limited, because of
the killer activity of NK cells that was predominantly induced
by only IFN-a, not IFNL1. On the other hands, type III IFN
responses using PHH culture in vitro against 5’-triphosphate
single stranded RNA (PPP-RNA) transfection (mimic of HCV
infection) were varied from IFNL3-IFNL4 variants, although the
levels of IFN-λ genes were significantly higher in PHHs with
favorable genotype than that with unfavorable genotype by
PPP-RNA. The knockdown experiment by small interfering RNA
indicated that cytosol RNA sensor was the key molecule of IFNL
production. When PHHs were infected with HBV, IFN-λ genes
were induced after HBV infection in PHHs with favorable genotype,
but not unfavorable genotype. Conclusions: Our results
suggest that a response of human hepatocytes against hepatotropic
viruses could be contribute to type III IFN production and
the responses might be depended to the IFNL3-IFNL4 variants.
Disclosures:
Yasuhito Tanaka - Grant/Research Support: Chugai Pharmaceutical CO., LTD.,
MSD, Bristol-Myers Squibb; Speaking and Teaching: janssen pharma, Bristol-Myers
Squibb
The following authors have nothing to disclose: Tsunamasa Watanabe, Susumu
Tsutsumi, Kentaro Matsuura, Etsuko Iio, Noboru Shinkai, Kayoko Matsunami,
Fumio Itoh
1007
Altered frequencies and function of MAIT cells during
treatment of patients with chronic HCV, HIV and HCV/
HIV co-infections
Michelle Spaan 2 , Sebastiaan Hullegie 1 , Kim Kreefft 2 , Gertine van
Oord 2 , Boris Beudeker 2 , Bart J. Rijnders 1 , Robert J. de Knegt 2 ,
Mark Claassen 1 , Andre Boonstra 2 ; 1 Department of Internal Medicine,
Erasmus MC, Rotterdam, Netherlands; 2 Department of
Gastroenterology and Hepatology, Erasmus MC, Rotterdam, Netherlands
Background Mucosal invariant T (MAIT) cells comprise a subpopulation
of T cells that can be activated by a broad range of
bacterial products and cytokines to produce IFN-γ and express
cytolytic enzymes. Loss of MAIT cells is observed in HIV infection,
which is thought to compromise anti-bacterial immunity
and microbial translocation in the gut. Since little is known
on the MAIT cells during HCV infection, we compared their
phenotype and function in comparison to HIV and HCV/ HIV
co-infection, and determined the effect of IFN-based and DAA
antiviral therapy on MAIT cells for HCV. Methods Peripheral
blood was collected before, during and 24 weeks after therapy
from patients with chronic HCV (n=27), virologically supressed
chronic HIV (n=10), HCV/HIV co-infection (n=9) and healthy
individuals (n=12) before, during and after therapy. Patients
with HCV were treated with pegIFN-α/ribavirin with and without
telaprevir, or boceprevir or with IFN-free therapy. MAIT
cells were identified on the basis of CD161 and Vα7.2, and
were stimulated with E.coli, IL-12/IL-18 or IL-18/IFN-α for 18
hours. NK cells and MAIT cells were analysed for the expression
of CD38, CD69 and IFN-γ by flowcytometry. Results Compared
to healthy individuals, the frequency of MAIT cells was
significantly decreased in patients with chronic HCV, HIV and
HCV/ HIV co-infection (5.6%, 3.2%, 2.0% and 1.0% within
CD3+ T cells, respectively). Expression of CD38 on MAIT cells
was comparable in chronic HCV, HIV and healthy individuals,
but was significantly increased in patients with HIV/HCV
co-infection. MAIT cells from healthy controls and the 3 patient
populations were responsive to IFNα in vitro as evidenced by
enhanced frequencies of CD69 expressing and IFN-γ producing
cells. After successful IFN-based therapy the frequencies of
MAIT cells did not normalize. However, we observed that the
functionality of MAIT cells was differentially affected during the
course IFN-α-based therapy and was highly dependent on the
treatment regimen and patient group. Importantly, viral load
decline by IFN-free DAA treatment led to strongly enhanced
IFN-γ levels. Conclusion We show that the frequencies of MAIT
cells are reduced in blood of patients with chronic HCV, HIV
and in HCV/HIV co-infection compared to healthy individuals.
The potent effects on MAIT cells of exposure to IFN-α, both in
vitro and in vivo, and HCV and HIV RNA levels warrant more
detailed studies on the interplay between infections to the activity
of this specialized T cell subpopulation.
Disclosures:
Bart J. Rijnders - Advisory Committees or Review Panels: BMS, Abbvie, Gilead;
Grant/Research Support: MSD, Gilead
Robert J. de Knegt - Advisory Committees or Review Panels: Roche, Norgine,
Janssen Cilag, AbbVie; Grant/Research Support: Roche, Janssen Cilag, BMS,
AbbVie; Speaking and Teaching: Gilead, Roche, Janssen Cilag, AbbVie
Andre Boonstra - Grant/Research Support: BMS, Janssen Pharmaceutics, Merck,
Roche, Gilead
The following authors have nothing to disclose: Michelle Spaan, Sebastiaan Hullegie,
Kim Kreefft, Gertine van Oord, Boris Beudeker, Mark Claassen
1008
Interferon-based treatment activates regulatory CD4 +
T-cells to exert counteractive antiviral immunity
Bettina Langhans, Hans Dieter Nischalke, Philipp Lutz, Benjamin
Krämer, Christian P. Strassburg, Jacob Nattermann, Ulrich Spengler;
Department of Internal Medicine I, University of Bonn, Bonn,
Germany
Background and aims: Regulatory CD4 + T cells (Tregs) accumulate
during chronic hepatitis C virus (HCV) infection and
inhibit anti-viral T cell responses. The availability of direct-acting
antiviral agents (DAAs), which can be applied in combination
with pegylated interferon (IFN) or as IFN-free regimens
have revolutionized treatment options. However, their effect on
altered immunoregulation in hepatitis C is unclear. Here, we
studied Tregs before and after elimination of HCV with DAAs
combined with IFN versus IFN-free therapy. Methods: Using