Integrin alpha vs1 Is a Receptor for Foot-and-Mouth Disease Virus

Infection by field strains of Foot-and-mouth disease virus (FMDV) is initiated by binding to certain species of arginine-glycine-aspartic acid (RGD)- dependent integrin including alpha vs3 and the epithelial integrin alpha vs6. In this report we show that the integrin alpha vs1, when expressed as a human/hamster heterodimer on transfected CHOB2 cells, is a receptor for FMDV. Virus binding and infection mediated by alpha vs1 was inefficient in the presence of physiological concentrations of calcium and magnesium but were significantly enhanced by reagents that activate the integrin and promote ligand binding. The ability of chimeric alpha 5/ alpha v integrin subunits, in association with the s1 chain, to bind FMDV and mediate infection matched the ligand binding specificity of alpha vs1, not alpha 5s1, thus providing further evidence for the receptor role of alpha vs1. In addition, data are presented suggesting that amino acid residues near the RGD motif may be important for differentiating between the binding specificities of alpha vs1 and alpha vs6.