title: Active cross-protection induced by a recombinant baculovirus expressing chimeric infectious bursal disease virus structural proteins.
abstract: The VP2 structural gene encoded in the large genomic segment A of the variant GLS strain of infectious bursal disease virus (IBDV) was modified to encode a neutralization epitope (B69), found only on classic strains of IBDV. A chimeric cDNA clone of the large segment A, encoding VP3, VP4, and the modified variant IBDV VP2 structural proteins, was expressed in a recombinant baculovirus. The chimeric protein expressed was assessed with a panel of neutralizing monoclonal antibodies (MAbs), and it contained not only all previously MAb-defined GLS variant strain epitopes but also the B69 neutralization epitope found on classic IBDV strains. Complete active protection was afforded to specific-pathogen-free chickens by a subunit chimeric vaccine against virulent challenge with the classic IM and STC strains, as well as against the variant E/Del and GLS IBDV strains. Compared with a previously tested recombinant subunit vaccine, which incorporated unmodified baculovirus-expressed large-segment A GLS proteins, the recombinant chimeric subunit vaccine resulted in markedly improved active cross-protection against classic IBDV challenge.
authors.affiliation: Virginia-Maryland Regional College of Veterinary Medicine, University of Maryland, College Park 20742.
authors.forename: D B
authors.initials: DB
authors.lastname: Snyder
authors.forename: V N
authors.initials: VN
authors.lastname: Vakharia
authors.forename: S A
authors.initials: SA
authors.lastname: Mengel-Whereat
authors.forename: G H
authors.initials: GH
authors.lastname: Edwards
authors.forename: P K
authors.initials: PK
authors.lastname: Savage
authors.forename: D
authors.initials: D
authors.lastname: Lütticken
authors.forename: M A
authors.initials: MA
authors.lastname: Goodwin
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000235:genetics; D018175:Birnaviridae Infections / Q000276:immunology / Q000517:prevention & control / Q000662:veterinary*; D002645:Chickens / Q000276:immunology* / Q000821:virology; D003429:Cross Reactions; D015967:Gene Expression Regulation, Viral; D007243:Infectious bursal disease virus / Q000235:genetics / Q000276:immunology*; D011201:Poultry Diseases / Q000517:prevention & control*; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000276:immunology*; D015678:Viral Structural Proteins / Q000235:genetics / Q000276:immunology*; D014765:Viral Vaccines / Q000235:genetics / Q000276:immunology*
chemical_list: D011993:Recombinant Fusion Proteins; D015678:Viral Structural Proteins; D014765:Viral Vaccines