MAPPING OF ANTIGENIC SITES INVOLVED IN NEUTRALIZATION ON THE CAPSID PROTEIN OF FELINE CALICIVIRUS

In order to locate amino acid residues involved in the formation of fe line calicivirus (FCV) neutralizing epitopes, we analysed the capsid p rotein gene of monoclonal antibody neutralization-resistant variants o f FCV. Amino acid substitutions in the variants were identified in the two hypervariable regions of the capsid protein. Four linear and two conformational epitopes were located in the regions from residues 426 to 460 and 490 to 520, respectively. The relative positions of individ ual epitopes agreed with our previous antigenic analysis. Two antigeni c sites composed of the neutralizing epitopes were mapped in the hyper variable regions of the capsid protein, demonstrating that a relations hip exists between the genetic variability and antigenic differences i n the neutralization of FCV.