Basic Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Gastroenterol. Dec 7, 2016; 22(45): 9954-9965
Published online Dec 7, 2016. doi: 10.3748/wjg.v22.i45.9954
Apolipoprotein B100 is required for hepatitis C infectivity and Mipomersen inhibits hepatitis C
Esperance A K Schaefer, James Meixiong, Christina Mark, Amy Deik, Daniel L Motola, Dahlene Fusco, Andrew Yang, Cynthia Brisac, Shadi Salloum, Wenyu Lin, Clary B Clish, Lee F Peng, Raymond T Chung
James Meixiong, Christina Mark, Daniel L Motola, Dahlene Fusco, Andrew Yang, Cynthia Brisac, Shadi Salloum, Wenyu Lin, Lee F Peng, Raymond T Chung, Esperance AK Schaefer, Gastrointestinal Unit, Massachusetts General Hospital, Boston, MA 02114, United States
Daniel L Motola, Lee F Peng, Raymond T Chung, Esperance AK Schaefer, Department of Medicine, Harvard Medical School, Boston, MA 02115, United States
Clary B Clish, Amy Deik, both of the Broad Institute of Harvard and M.I.T., Cambridge, MA 02142, United States
Lee F Peng, Temple University Health System, Philadelphia, PA 19140, United States
Author contributions: Schaefer EAK designed and interpreted all experiments and prepared the manuscript; Meixiong J, Mark C, Fusco D, Yang A, Brisac C, Salloum S and Lin W assisted in designing and interpreting entry, replicon and infectivity assays; Meixiong J and Mark C assisted with designing and interpreting experiments involving mipomersen; Motola DL performed TALEN cell line generation and design of experiments; Peng LF and Chung RT designed and interpreted all experiments and prepared the manuscript; Peng LF and Chung RT contributed equally to this manuscript; all the authors contributed to this manuscript.
Supported by the United States National Institutes of Health (NIH), No. F32-DK097855 (to Schaefer EAK), No. T32-DK008191 (to Motola DL), No. K08-DK088951 (to Peng LF), and No. K24-DK078772 (to Chung RT).
Institutional review board statement: No patients or patient-derived samples were involved in this study.
Conflict-of-interest statement: The authors have no conflicts of interest to declare.
Data sharing statement: Technical appendix and data set available from the corresponding author.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Lee F Peng, Associate Medical Director of Liver Transplantation, Associate Professor of Medicine, Temple University Health System, 3509 N. Broad St., 9th Floor, Philadelphia, PA 19140, United States. lee.peng@tuhs.temple.edu
Telephone: +1-215-7075067 Fax: +1-215-7075124
Received: July 22, 2016
Peer-review started: July 25, 2016
First decision: September 20, 2016
Revised: October 1, 2016
Accepted: October 27, 2016
Article in press: October 27, 2016
Published online: December 7, 2016
Abstract
AIM

To characterize the role of apolipoprotein B100 (apoB100) in hepatitis C viral (HCV) infection.

METHODS

In this study, we utilize a gene editing tool, transcription activator-like effector nucleases (TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDA-approved antisense inhibitor of apoB100, on HCV using in vitro cell-culture competent HCV and determined its impact on viral infectivity with the TCID50 method.

RESULTS

We found that apoB100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALEN-mediated gene deletion of apoB (APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apoB did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wild-type virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus.

CONCLUSION

ApoB is required for the generation of fully infectious HCV virions, and inhibition of apoB with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.

Keywords: Apolipoprotein, Lipid, Hepatitis C virus, Gene silencing, Viral replication

Core tip: Hepatitis C virus (HCV) circulates as a very-low-density lipoprotein (VLDL)-like lipoviral particle. Apolipoprotein B100 (apoB100) is the core protein of VLDL, buts its role in HCV has remained incompletely characterized. Use of gene-editing with transcription activator-like effector nucleases permits the characterization of the role of apoB100 in HCV. We demonstrate that apoB100 is required for HCV infection. Loss of apoB100 results in the secretion of HCV virions with an altered lipid composition and limited ability to infect naive cells. Mipomersen, an FDA-approved antisense inhibitor of apoB100, has an anti-HCV effect and limits the viral infectivity.