title: A new in vitro hemagglutinin inhibitor screening system based on a single-vesicle fusion assay.
abstract: Hemagglutinin (HA) from the influenza virus plays a pivotal role in the infection of host mammalian cells and is, therefore, a druggable target, similar to neuraminidase. However, research involving the influenza virus must be conducted in facilities certified at or above Biosafety Level 2 because of the potential threat of the contagiousness of this virus. To develop a new HA inhibitor screening system without intact influenza virus, we conceived a single-vesicle fusion assay using full-length recombinant HA. In this study, we first showed that full-length recombinant HA can mediate membrane fusion in ensemble and single-vesicle fusion assays. The fluorescence resonance energy transfer (FRET) frequency pattern of single-vesicle complexes completely differed when the inhibitors targeted the HA1 or HA2 domain of HA. This result indicates that analysing the FRET patterns in this assay can provide information regarding the domains of HA inhibited by compounds and compounds' inhibitory activities. Therefore, our results suggest that the assay developed here is a promising tool for the discovery of anti-influenza virus drug candidates as a new in vitro inhibitor screening system against HA from the influenza virus.
authors.affiliation: Center for Nutraceutical and Pharmaceutical Materials, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.
authors.forename: Hanki
authors.initials: H
authors.lastname: Lee
authors.affiliation: Laboratory of Molecular Disease and Cell Regulation, Department of Molecular Medicine, School of Medicine, Gacheon University, Incheon, 21936, Republic of Korea.|Gachon Medical Research Institute, Gil Medical Center, Incheon, 21565, Republic of Korea.
authors.forename: Wook
authors.initials: W
authors.lastname: Jin
authors.affiliation: Division of Biosciences and Bioinformatics, College of Natural Science, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.
authors.forename: Byeong-Chul
authors.initials: BC
authors.lastname: Jeong
authors.affiliation: Center for Nutraceutical and Pharmaceutical Materials, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.|Division of Biosciences and Bioinformatics, College of Natural Science, Myongji University, Yongin, Gyeonggi-do, 17058, Republic of Korea.
authors.forename: Joo-Won
authors.initials: JW
authors.lastname: Suh
mesh_terms: D000998:Antiviral Agents / Q000302:isolation & purification* / Q000494:pharmacology*; D004353:Drug Evaluation, Preclinical / Q000379:methods*; D031541:Fluorescence Resonance Energy Transfer; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000378:metabolism*; D008561:Membrane Fusion / Q000187:drug effects; D009975:Orthomyxoviridae / Q000187:drug effects*
chemical_list: D000998:Antiviral Agents; D019267:Hemagglutinin Glycoproteins, Influenza Virus