A Novel Inhibitor IDPP Interferes with Entry and Egress of HCV by Targeting Glycoprotein E1 in a Genotype-Specific Manner

Abstract

Despite recent advances in curing chronic hepatitis C (CHC), the high economic burden to therapy, viral drug resistance, difficult to treat hepatitis C virus (HCV) genotypes and patient groups are still of concern. To address this unmet medical needs, we devised strategies to identify novel viral interventions through target-free high-throughput screening of small molecules utilizing a phenotypic-based HCV infection assay. Thereby, a very potent (EC50 46 ± 26 pM) iminodipyridinopyrimidine (IDPP) drug candidate was selected, and confirmed in primary human hepatocytes (EC50 0.5 nM). IDPP mainly targets a post-attachment step of HCV without affecting endosomal acidification, prevents the secretion of infectious particles and viral cell-to-cell spread. The putative molecular target of IDPP is glycoprotein E1, as revealed by selection for viral drug resistance (Gly-257-Arg). IDPP was synergistic in combination with FDA-approved HCV drugs and inhibited pre-existing resistant HCV strains induced by today’s therapies. Interestingly, IDPP exclusively inhibited HCV genotype 2. However, we identified the genotype-specificity determining region in E1 and generated HCV genotype 1 susceptible to IDPP by changing one amino acid in E1 (Gln-257-Gly). Together, our results indicate an opportunity to provide an alternative treatment option for CHC and will shed light on the poorly understood function of HCV glycoprotein E1.

Discovery and development of safe-in-man broad-spectrum antiviral agents

“…For example, TZM-bl cells expressing firefly luciferase under control of HIV-1 LTR promoter allowed quantitation of BSAA action on HIV-1 infection (tat-protein expression by integrated HIV-1 provirus) using firefly luciferase assay (Sarzotti-Kelsoe et al, 2014;Xing et al, 2016). RFPexpressing RVFV, nanoLuc-expressing CHIKV and RRV, as well as GFP-expressing FLUAV, HCV and HMPV also allowed identification of novel activities of several BSAAs (Andersen et al, 2019b;Bosl et al, 2019;de Graaf et al, 2007;Habjan et al, 2008;Ianevski et al, 2018;Jupille et al, 2011;Kittel et al, 2004;Lee et al, 2017;Utt et al., 2016). In addition, qPCR/RT-qPCR, RNA/DNA sequencing, RNA/DNA hybridization, immuno-and plaque assays as well as CRISPR-CAS9 systems could be used for detection of inhibitory effects of BSAAs (Boonham et al, 2014;Fischer et al, 2017;Konig et al, 2019;Laamiri et al, 2018;Landry, 1990;Perez et al, 2013;Sashital, 2018;Zhou et al, 2018).…”

Discovery and Development of Safe-in-Man Broad-Spectrum Antiviral Agents

“…For example, TZM-bl cells expressing firefly luciferase under control of HIV-1 LTR promoter allowed quantitation of BSAA action on HIV-1 infection (tat-protein expression by integrated HIV-1 provirus) using firefly luciferase assay (23,24). RFP-expressing RVFV, nanoLucexpressing CHIKV and RRV, as well as GFP-expressing FLUAV, HCV and HMPV also allowed identification of novel activities of several BSAAs (13,21,(25)(26)(27)(28)(29)(30)(31). In addition, qPCR/RT-qPCR, RNA/DNA sequencing, RNA/DNA hybridization, immuno-and plaque assays as well as CRISPR-CAS9 systems could be used for detection of inhibitory effects of BSAAs (32)(33)(34)(35)(36)(37)(38)(39).…”

Discovery and Development of Safe-in-Man Broad-Spectrum Antiviral Agents

“…For example, TZM-bl cells expressing firefly luciferase under control of HIV-1 LTR promoter allowed quantitation of BSAA action on HIV-1 infection (tat-protein expression by integrated HIV-1 provirus) using firefly luciferase assay (Sarzotti-Kelsoe et al, 2014;Xing et al, 2016). RFPexpressing RVFV, nanoLuc-expressing CHIKV and RRV, as well as GFP-expressing FLUAV, HCV and HMPV also allowed identification of novel activities of several BSAAs (Andersen et al, 2019b;Bosl et al, 2019;de Graaf et al, 2007;Habjan et al, 2008;Ianevski et al, 2018;Jupille et al, 2011;Kittel et al, 2004;Lee et al, 2017;Utt et al, 2016). In addition, qPCR/RT-qPCR, RNA/DNA sequencing, RNA/DNA hybridization, immuno-and plaque assays as well as CRISPR-CAS9 systems could be used for detection of inhibitory effects of BSAAs (Boonham et al, 2014;Fischer et al, 2017;Konig et al, 2019;Laamiri et al, 2018;Landry, 1990;Perez et al, 2013;Sashital, 2018;Zhou et al, 2018).…”