title: Immunization with VP2 is sufficient for protection against lethal challenge with African horsesickness virus Type 4.
abstract: Horses were immunized by inoculation with a vaccinia construct containing a full-length cDNA corresponding to the L2 gene segment of African horsesickness virus type 4(AHSV-4). All immunized horses developed serum neutralizing antibodies prior to challenge with virulent AHSV-4. No ELISA-reactive antibodies were present prior to challenge. A group of four seronegative control horses died after developing clinical signs and lesions typical of the pulmonary form of African horsesickness while the immunized horses were clinically normal. Increases in serum neutralizing and ELISA-reactive antibody titers following challenge indicate that at least some replication of challenge virus occurred in immunized horses. These results demonstrate that AHSV VP2 alone is sufficient to induce a protective immune response in horses and indicate the usefulness of ELISA-reactive antibodies for differentiation of vaccinated and naturally exposed horses.
authors.affiliation: Molecular Pathology Unit, Plum Island Animal Disease Center, USDA, Greenport, New York 11944-0848, USA.
authors.forename: M A
authors.initials: MA
authors.lastname: Stone-Marschat
authors.forename: S R
authors.initials: SR
authors.lastname: Moss
authors.forename: T G
authors.initials: TG
authors.lastname: Burrage
authors.forename: M L
authors.initials: ML
authors.lastname: Barber
authors.forename: P
authors.initials: P
authors.lastname: Roy
authors.forename: W W
authors.initials: WW
authors.lastname: Laegreid
mesh_terms: D000355:African Horse Sickness / Q000276:immunology / Q000517:prevention & control*; D000356:African Horse Sickness Virus / Q000276:immunology*; D000818:Animals; D000914:Antibodies, Viral / Q000097:blood / Q000276:immunology; D002213:Capsid / Q000235:genetics / Q000276:immunology*; D036022:Capsid Proteins; D002522:Chlorocebus aethiops; D006736:Horses; D007114:Immunization; D014614:Vaccines, Synthetic / Q000276:immunology; D014709:Vero Cells; D014765:Viral Vaccines / Q000276:immunology*
chemical_list: D000914:Antibodies, Viral; D036022:Capsid Proteins; C442519:VP2 protein, African horse sickness virus; D014614:Vaccines, Synthetic; D014765:Viral Vaccines