title: Foot-and-mouth disease virus (FMDV) with a stable FLAG epitope in the VP1 G-H loop as a new tool for studying FMDV pathogenesis.
abstract: Foot-and-mouth disease virus (FMDV) VP1 G-H loop contains the major antigenic site. By replacing the sequence upstream of the RGD motif with a FLAG epitope, a marker virus for pathogenesis studies was generated. In cell culture, the recombinant virus containing FLAG (A24-FLAG) exhibited similar plaque phenotypes and growth kinetics to parental virus. A24-FLAG was distinguished, neutralized, and immunoprecipitated by FLAG anti-sera. A24-FLAG infected cattle exhibited FMD and an antibody response similar to parental virus. FLAG epitope stability was confirmed both in vitro and in vivo. Interestingly, no anti-FLAG antibodies were detectable in cattle up to 21 days post-inoculation. A24-FLAG G-H loop modeling suggested FLAG was rendered a cryptic site, inaccessible to the host immune system. These studies demonstrate the FMDV VP1 G-H loop tolerance to substitutions without detriment to pathogenesis and antigenicity. Finally, A24-FLAG manifested virulence in cattle as parental virus, and could be distinguished and tracked by tag-specific anti-sera.
authors.affiliation: Foreign Animal Disease Research Unit, United States Department of Agriculture, Agricultural Research Service, Plum Island Animal Disease Center, Greenport, NY 11944, United States.
authors.forename: Paul
authors.initials: P
authors.lastname: Lawrence
authors.forename: Juan M
authors.initials: JM
authors.lastname: Pacheco
authors.forename: Sabena
authors.initials: S
authors.lastname: Uddowla
authors.forename: Jason
authors.initials: J
authors.lastname: Hollister
authors.forename: Abhay
authors.initials: A
authors.lastname: Kotecha
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Fry
authors.forename: Elizabeth
authors.initials: E
authors.lastname: Rieder
mesh_terms: D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D000956:Antigens, Viral / Q000276:immunology; D036022:Capsid Proteins / Q000737:chemistry* / Q000235:genetics / Q000276:immunology*; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000821:virology; D002460:Cell Line; D006224:Cricetinae; D000939:Epitopes / Q000235:genetics / Q000276:immunology; D005536:Foot-and-Mouth Disease / Q000276:immunology / Q000473:pathology* / Q000821:virology*; D029544:Foot-and-Mouth Disease Virus / Q000235:genetics / Q000276:immunology* / Q000472:pathogenicity*; D009842:Oligopeptides; D010455:Peptides / Q000235:genetics / Q000276:immunology*; D017434:Protein Structure, Tertiary
chemical_list: D000914:Antibodies, Viral; D000956:Antigens, Viral; D036022:Capsid Proteins; D000939:Epitopes; D009842:Oligopeptides; D010455:Peptides; C442501:VP1 protein, Foot-and-mouth disease virus; C085706:FLAG peptide