1999 Volume 61 Issue 8 Pages 935-938
The type II feline infectious peritonitis virus (FIPV) epitopes for neutralizing and enhancing antibodies are present on large spike glycoprotein (S) protein. In this study, we established monoclonal antibody-resistant mutant viruses resistant to three different monoclonal antibodies with neutralizing activity in Felis catus whole fetus cells and enhancing activity in feline macrophages, recognizing distinct epitopes on type II FIPV S protein. By comparing the nucleotide sequences of these mutant viruses with that of wild-type virus, we attempted to identify the neutralizing epitopes. The mutations were localized in the region of amino acid residues from 480 to 649 from the N terminal of the S protein.