A screen for inhibitory peptides of hepatitis C virus identifies a novel entry inhibitor targeting E1 and E2

Peiqi Yin,Yao Deng,Yi-Ping Li,Ling Zhang,Wenjie Tan,Leiliang Zhang,Fei Ye,Sha Lu

doi:10.1038/s41598-017-04274-8

Abstract

Hepatitis C virus (HCV) entry into hepatocytes is a multistep process that represents a promising target for antiviral intervention. The viral envelope protein E1E2 plays a critical role in HCV entry. In this study, we sought to identify peptide inhibitors of HCV by screening a library of overlapping peptides covering E1E2. Screening the peptide library identified several novel anti-HCV peptides. Four peptides from glycoprotein E2 were selected for further investigation. The 50% effective dose (ED50) was approximately 5 nM for each peptide. Our data indicated that these peptides inhibited HCV entry at the post-attachment step. Moreover, these peptides blocked cell-to-cell transmission of HCVcc and had broad-spectrum antiviral effects on HCVcc. These peptides exhibited combination inhibitory effects on HCVcc infection when combined with IFN-α2b or anti-CD81 antibody. Interestingly, we observed that E2-42 associated with E1 and E2. Our results indicate that E2-42 inhibits HCV entry via E1 and E2. These findings suggest a new avenue for HCV therapeutic development.

Highlights

As a member of the Flaviviridae family, Hepatitis C virus (HCV) is an enveloped positive-sense single-strand RNA virus
Because the strategy of developing antiviral peptides based on viral membrane proteins is feasible, systematic screening of anti-HCV peptides from HCV E1E2 is promising
Each peptide consisted of 15 amino acids (AA) composed of two adjacent overlapping 10-AA or 11-AA regions

Summary

Introduction

As a member of the Flaviviridae family, HCV is an enveloped positive-sense single-strand RNA virus. Due to its multi-step nature, HCV entry is an attractive target for inhibiting HCV. Short peptides derived from viral envelope www.nature.com/scientificreports/. Sequences that contain membrane-transiting motifs have been designed to inhibit virus entry into cells. A peptide derived from the amino acids 710 to 725 of the HCV E2, inhibits HCV pseudoparticle infection[15]. The amphipathic α-helical peptide C5A derived from the membrane anchor domain of the HCV NS5A protein exhibits significant inhibitory effects against HCV infection in vitro[16]. Because the strategy of developing antiviral peptides based on viral membrane proteins is feasible, systematic screening of anti-HCV peptides from HCV E1E2 is promising. We screened a peptide library from JFH1 E1E2 and identified four novel HCV inhibitory peptides functioning at the post-attachment and viral spread steps. Our work opens a new avenue for screening anti-HCV peptides and uncovers potential anti-HCV agents

Methods

Results

Conclusion