title: CL-385319 inhibits H5N1 avian influenza A virus infection by blocking viral entry.
abstract: CL-385319, an N-substituted piperidine, is effective in inhibiting infection of H1-, H2-, and to a lesser extent, H3-typed influenza A viruses by interfering with the fusogenic function of the viral hemagglutinin. Here we show that CL-385319 is effective in inhibiting infection of highly pathogenic H5N1 influenza A virus in Madin-Darby Canine Kidney (MDCK) cells with an IC50 of 27.03±2.54 μM. This compound with low cytotoxicity (CC50=1.48±0.01 mM) could also inhibit entry of pseudoviruses carrying hemagglutinins from H5N1 strains that were isolated from different places at different times, while it had no inhibitory activity on the entry of VSV-G pseudotyped particles. CL385319 could not inhibit N1-typed neuraminidase activity and the adsorption of H5-typed HA to chicken erythrocytes at the concentration as high as 1 mg/ml (2.8 mM). Computer-aid molecular docking analysis suggested that CL-385319 might bind to the cavity of HA2 stem region which was known to undergo significant rearrangement during membrane fusion. Pseudoviruses with M24A mutation in HA1 or F110S mutation in HA2 were resistant to CL-385319, indicating that these two residues in the cavity region may be critical for CL-385319 bindings. These findings suggest that CL-385319 can serve as a lead for development of novel virus entry inhibitors for preventing and treating H5N1 influenza A virus infection.
authors.affiliation: School of Pharmaceutical Sciences, Southern Medical University, Guangzhou 510515, China. liusw@smu.edu.cn
authors.forename: Shuwen
authors.initials: S
authors.lastname: Liu
authors.forename: Runming
authors.initials: R
authors.lastname: Li
authors.forename: Ruitao
authors.initials: R
authors.lastname: Zhang
authors.forename: Chris C S
authors.initials: CC
authors.lastname: Chan
authors.forename: Baomin
authors.initials: B
authors.lastname: Xi
authors.forename: Zhibo
authors.initials: Z
authors.lastname: Zhu
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Vincent K M
authors.initials: VK
authors.lastname: Poon
authors.forename: Jie
authors.initials: J
authors.lastname: Zhou
authors.forename: Min
authors.initials: M
authors.lastname: Chen
authors.forename: Jan
authors.initials: J
authors.lastname: Münch
authors.forename: Frank
authors.initials: F
authors.lastname: Kirchhoff
authors.forename: Stephan
authors.initials: S
authors.lastname: Pleschka
authors.forename: Thomas
authors.initials: T
authors.lastname: Haarmann
authors.forename: Ursula
authors.initials: U
authors.lastname: Dietrich
authors.forename: Chungen
authors.initials: C
authors.lastname: Pan
authors.forename: Lanying
authors.initials: L
authors.lastname: Du
authors.forename: Shibo
authors.initials: S
authors.lastname: Jiang
authors.forename: Bojian
authors.initials: B
authors.lastname: Zheng
mesh_terms: D000818:Animals; D000998:Antiviral Agents / Q000378:metabolism / Q000494:pharmacology* / Q000633:toxicity; D001549:Benzamides; D004285:Dogs; D057809:HEK293 Cells; D019267:Hemagglutinin Glycoproteins, Influenza Virus / Q000737:chemistry / Q000378:metabolism; D006801:Humans; D006845:Hydrocarbons, Fluorinated / Q000378:metabolism / Q000494:pharmacology* / Q000633:toxicity; D053124:Influenza A Virus, H5N1 Subtype / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D008958:Models, Molecular; D010880:Piperidines / Q000378:metabolism / Q000494:pharmacology* / Q000633:toxicity; D011487:Protein Conformation; D053586:Virus Internalization / Q000187:drug effects*
chemical_list: C560737:3-fluoro-N-(2-(1-piperidinyl)ethyl)-5-(trifluoromethyl)benzamide; D000998:Antiviral Agents; D001549:Benzamides; D019267:Hemagglutinin Glycoproteins, Influenza Virus; D006845:Hydrocarbons, Fluorinated; D010880:Piperidines; C109963:hemagglutinin, avian influenza A virus