ANTIBODY RECOGNITION AND NEUTRALIZATION OF FOOT-AND-MOUTH-DISEASE VIRUS

Foot-and-mouth disease virus occurs as seven distinct serotypes which do not display any cross neutralization. There is also considerable antigenic variation within each serotype. This variation is surprising because, in all of the many isolates of the virus that have been sequenced the triplet Arg Gly Asp, which is important in cell attachment, is present as residues 145, 146, 147 on a prominent surface loop of VP1, one of the four capsid proteins. However, this triplet is surrounded by amino acids which vary considerably between isolates. Moreover; a single amino acid substitution in the immediate vicinity of the Arg Gly Asp triplet, at positions 148 or 153, is sufficient to confer specificity. This variation has considerable implications for virus-antibody interaction for the control of the disease by vaccination.