Antiviral Potential of a Novel Compound CW-33 against Enterovirus A71 via Inhibition of Viral 2A Protease

作者:Wang Ching Ying; Huang An Cheng; Hour Mann Jen; Huang Su Hua; Kung Szu Hao; Chen Chao Hsien; Chen I Chieh; Chang Yuan Shiun; Lien Jin Cherng*; Lin Cheng Wen
来源:Viruses-Basel, 2015, 7(6): 3155-3171.
DOI:10.3390/v7062764

摘要

Enterovirus A71 (EV-A71) in the Picornaviridae family causes hand-foot-and-mouth disease, aseptic meningitis, severe central nervous system disease, even death. EV-A71 2A protease cleaves Type I interferon (IFN)-alpha/beta receptor 1 (IFNAR1) to block IFN-induced Jak/STAT signaling. This study investigated anti-EV-A7l activity and synergistic mechanism(s) of a novel furoquinoline alkaloid compound CW-33 alone and in combination with IFN-beta. Anti-EV-A71 activities of CW-33 alone and in combination with IFN-beta were evaluated by inhibitory assays of virus-induced apoptosis, plaque formation, and virus yield. CW-33 showed antiviral activities with an IC50 of near 200 mu M in EV-A71 plaque reduction and virus yield inhibition assays. While, anti-EV-A71 activities of CW-33 combined with 100 U/mL IFN-beta exhibited a synergistic potency with an IC50 of approximate 1 mu M in plaque reduction and virus yield inhibition assays. Molecular docking revealed CW-33 binding to EV-A71 2A protease active sites, correlating with an inhibitory effect of CW33 on in vitro enzymatic activity of recombinant 2A protease (IC50 = 53.1 mu M). Western blotting demonstrated CW-33 specifically inhibiting 2A protease-mediated cleavage of IFNAR1. CW-33 also recovered Type I IFN-induced Tyk2 and STAT1 phosphorylation as well as 2 ',5 '-OAS upregulation in EV-A71 infected cells. The results demonstrated CW-33 inhibiting viral 2A protease activity to reduce Type I IFN antagonism of EV-A71. Therefore, CW-33 combined with a low-dose of Type I IFN could be applied in developing alternative approaches to treat EV-A71 infection.