Review
Copyright ©The Author(s) 2015. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Hepatol. Oct 18, 2015; 7(23): 2449-2458
Published online Oct 18, 2015. doi: 10.4254/wjh.v7.i23.2449
Programmed death-1/programmed death-L1 signaling pathway and its blockade in hepatitis C virus immunotherapy
Mohamed L Salem, Ahmed El-Badawy
Mohamed L Salem, Center of Excellence in Cancer Research, Tanta University, Tanta 31527, Egypt
Mohamed L Salem, Immunology and Biotechnology Division, Zoology Department, Faculty of Science, Tanta 31527, Egypt
Ahmed El-Badawy, Center of Excellence for Stem Cells and Regenerative Medicine, Zewail City of Science and Technology, 6th of October City, Giza 12588, Egypt
Author contributions: Salem ML and El-Badawy A contributed equally to this work.
Supported by Science and Technology Development Fund (STDF; grants No. 1469 and No. 5245); and Tanta University Fund, Egypt to Mohamed L Salem, the Principal investigator of these projects.
Conflict-of-interest statement: We declare that authors have no conflict of interest.
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: Mohamed L Salem, PhD, Professor, Center of Excellence in Cancer Research, Tanta University, Tanta 31527, Egypt. cecr@unv.tanta.edu.eg
Telephone: +20-12-74272624
Received: April 11, 2015
Peer-review started: April 15, 2015
First decision: June 2, 2015
Revised: June 29, 2015
Accepted: September 2, 2015
Article in press: September 7, 2015
Published online: October 18, 2015
Core Tip

Core tip: The programmed death-1 (PD-1)/PD-L1 pathway is an attractive target for anti-hepatitis C virus (HCV) immunotherapy because it restores the functional capacities of HCV-specific T cells. This is an extremely promising development in anti-HCV vaccines research since restoration of exhausted anti-HCV T cells is a major challenge when developing either prophylactic or therapeutic vaccines. This review will discuss the correlation between PD-1 expression and the clinical outcome in HCV patients and how this information can be potentially applied to block PD-1/PD-L1 pathway for HCV immunotherapy.