title: Caspase activation in equine influenza virus induced apoptotic cell death.
abstract: Equine influenza virus (EIV) is the leading cause of acute respiratory infection in horses worldwide. In recent years, the precise mechanism by which influenza infection kills host cells is being re-evaluated. In this report, we examined whether caspases, a group of intracellular proteases, are activated following EIV infection and contribute to EIV-mediated cell death. Western blotting analysis indicated that a nuclear target of caspase-3, poly(ADP-ribose) polymerase (PARP) was proteolytically cleaved in EIV-infected MDCK cells, but not in mock-infected cells. In comparison with caspase-3 specific inhibitor Ac-DEVD-CHO, a general caspase inhibitor Boc-D-FMK provided much stronger inhibition of EIV-induced cytopathic effect and apoptosis. Our results suggest that EIV may activate more than one caspase. Caspase activation and cleavage of its cellular targets may play a critical role in EIV-mediated cytotoxicity.
authors.affiliation: Department of Veterinary Science, The Maxwell H. Gluck Equine Research Center, University of Kentucky, Lexington, KY 40546-0099, USA. chengbin.lin@spcorp.com
authors.forename: Chengbin
authors.initials: C
authors.lastname: Lin
authors.forename: Robert E
authors.initials: RE
authors.lastname: Holland
authors.forename: Jennifer C
authors.initials: JC
authors.lastname: Donofrio
authors.forename: Morgan H
authors.initials: MH
authors.lastname: McCoy
authors.forename: Lynn R
authors.initials: LR
authors.lastname: Tudor
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Chambers
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000502:physiology*; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism*; D002460:Cell Line; D004789:Enzyme Activation; D004791:Enzyme Inhibitors / Q000494:pharmacology; D006734:Horse Diseases / Q000201:enzymology* / Q000473:pathology; D006736:Horses; D009980:Influenza A virus / Q000201:enzymology*; D009976:Orthomyxoviridae Infections / Q000201:enzymology / Q000473:pathology / Q000662:veterinary*; D014779:Virus Replication
chemical_list: D061945:Caspase Inhibitors; D004791:Enzyme Inhibitors; D020169:Caspases