Inability of FMDV replication in equine kidney epithelial cells is independent of integrin αvβ3 and αvβ6

Integrins can function as receptors for foot-and-mouth disease virus (FMDV) in epithelium. Horses are believed to be insusceptible to this disease, but the mechanism of resistance remains unclear. To detect whether FMDV can use integrin to attach to equine epithelial, we compared the utilities of alpha v beta 3 and alpha v beta 6 between bovine and equine kidney epithelial cells (KECs). Equine KECs showed almost equal efficiency to those of bovine. Further, the integrin alpha v, beta 3, and beta 6 subunits from bovine and equine were cloned and vectors were transfected into SW480 cells and COS-1 cells alone or together, and virus titers were used to determine the viral replication. In all cases, the virus reproduced successfully. Overall, FMDV can replicate in SW480 cells transfected with equine beta 3/beta 6 subunits and COS-1 cells transfected with equine alpha v beta 3/alpha v beta 6 integrins, but not in EKECs. These results indicated that failure of FMDV replication in EKECs was not attributed to integrin receptors. (C) 2016 Published by Elsevier Inc.