title: Definition of neutralizing sites on African horse sickness virus serotype 4 VP2 at the level of peptides.
abstract: The antigenic structure of African horse sickness virus (AHSV) serotype 4 capsid protein VP2 has been determined at the peptide level by PEPSCAN analysis in combination with a large collection of polyclonal antisera and monoclonal antibodies. VP2, the determinant for the virus serotype and an important target in virus neutralization, was found to contain 15 antigenic sites. A major antigenic region containing 12 of the 15 sites was identified in the region between residues 223 and 400. A second domain between residues 568 and 681 contained the three remaining sites. These sites were used for the synthesis of peptides, which were later tested in rabbits. Of the 15 synthetic peptides, three were able to induce neutralizing antibodies for AHSV-4, defining two neutralizing epitopes, 'a' and 'b', between residues 321 and 339, and 377 and 400, respectively. A combination of peptides representing both sites induced a more effective neutralizing response. Still, the relatively low neutralization titres make the possibility of producing a synthetic vaccine for AHSV unlikely. The complex protein-protein interaction of the outer shell of the viral capsid would probably require the presence of either synthetic peptides in the correct conformation or peptide segments from the different proteins VP2, VP5 and VP7.
authors.affiliation: INGENASA, Hnos García Noblejas 41, 28037 Madrid, Spain1.
authors.forename: Jorge L
authors.initials: JL
authors.lastname: Martínez-Torrecuadrada
authors.affiliation: Institute for Animal Science and Health (ID-Lelystad), Department of Molecular Recognition, Edelhertweg 15, 8219 PH Lelystad, The Netherlands2.
authors.forename: Jan P M
authors.initials: JPM
authors.lastname: Langeveld
authors.affiliation: Institute for Animal Science and Health (ID-Lelystad), Department of Molecular Recognition, Edelhertweg 15, 8219 PH Lelystad, The Netherlands2.
authors.forename: Rob H
authors.initials: RH
authors.lastname: Meloen
authors.affiliation: INGENASA, Hnos García Noblejas 41, 28037 Madrid, Spain1.
authors.forename: J Ignacio
authors.initials: JI
authors.lastname: Casal
mesh_terms: D000356:African Horse Sickness Virus / Q000276:immunology*; D000595:Amino Acid Sequence; D000818:Animals; D002213:Capsid / Q000276:immunology*; D036022:Capsid Proteins; D000939:Epitopes; D006736:Horses; D008969:Molecular Sequence Data; D009500:Neutralization Tests; D010446:Peptide Fragments / Q000276:immunology*; D011817:Rabbits; D012703:Serotyping
chemical_list: D036022:Capsid Proteins; D000939:Epitopes; D010446:Peptide Fragments; C442519:VP2 protein, African horse sickness virus