Antigenic stability of foot-and-mouth disease virus variants on serial passage in cell culture.
Two neutralizing monoclonal antibody (MAb)-resistant variants selected from an isolate of foot-and-mouth disease virus (FMDV) type A5 were repeatedly passaged in cell culture and monitored for susceptibility to neutralization by the selecting MAb. A variant isolated with a MAb to a conformational epitope (1-OG2) lost resistance in 20 passages, while a variant isolated with a MAb to a linear epitope (1-HA6) persisted for 30 passages. In both cases, the virus population emerging after passage was antigenically and genetically indistinguishable from the original wild-type parental virus (FMDV A5 Spain-86). Coinfection assays with the wild type and each variant, and between the variants, showed rapid conversion to a homogeneous population. Wild-type virus prevailed over the variants and for coinfection between the variants, the linear epitope variant 1-HA6. While both variants arose from a single nucleotide substitution and reversion to wild type occurred for each, it appears that the variant based on the continuous epitope (1-HA6) was more stable. We discuss the implications of these results for the antigenic diversity of FMDV and its relationship to virus evolution.
Gonzalez
M J
MJ
Plum Island Animal Disease Center, U.S. Department of Agriculture, Greenport, New York 11944-0848.
Saiz
J C
JC
Laor
O
O
Moore
D M
DM
D000818:Animals; D000911:Antibodies, Monoclonal / Q000276:immunology; D000914:Antibodies, Viral / Q000276:immunology; D005537:Aphthovirus / Q000276:immunology*; D002417:Cattle; D002478:Cells, Cultured; D066298:In Vitro Techniques; D009500:Neutralization Tests; D013997:Time Factors; D014764:Viral Proteins / Q000276:immunology
D000911:Antibodies, Monoclonal; D000914:Antibodies, Viral; D014764:Viral Proteins