title: Potential of a BPV1 L1 VLP vaccine to prevent BPV1- or BPV2-induced pseudo-sarcoid formation and safety and immunogenicity of EcPV2 L1 VLPs in horse.
abstract: We have previously shown that immunization of horses with bovine papillomavirus type 1 (BPV1) L1 virus-like particles (VLPs) is safe and highly immunogenic and that BPV1 and bovine papillomavirus type 2 (BPV2) are closely related serotypes. Here we evaluated the protective potential of a BPV1 L1 VLP vaccine against experimental BPV1 and BPV2 challenge and studied the safety and immunogenicity of a bivalent equine papillomavirus type 2 (EcPV2)/BPV1 L1 VLP vaccine. Fourteen healthy horses were immunized with BPV1 L1 VLPs (100 µg per injection) plus adjuvant on days 0 and 28, while seven remained unvaccinated. On day 42, all 21 horses were challenged intradermally at 10 sites of the neck with 107 BPV1 virions per injection. In analogy, 14 horses immunized twice with EcPV2 plus BPV1 L1 VLPs (50 µg each) and seven control animals were challenged with 107 BPV2 virions per injection. Immunization with BPV1 L1 VLPs alone induced a robust antibody response (day 42 median titre: 12 800), and BPV1-inoculated skin remained unchanged in 13/14 vaccinated horses. Immunization with the bivalent vaccine was safe, resulted in lower median day 42 antibody titres of 400 for BPV1 and 1600 for EcPV2 and conferred significant yet incomplete cross-protection from BPV2-induced tumour formation, with 11/14 horses developing small, short-lived papules. Control horses developed pseudo-sarcoids at all inoculation sites. The monovalent BPV1 L1 VLP vaccine proved highly effective in protecting horses from BPV1-induced pseudo-sarcoid formation. Incomplete protection from BPV2-induced tumour development conferred by the bivalent vaccine is due to the poorer immune response by immune interference or lower cross-neutralization titres to heterologous BPV2 virions.
authors.affiliation: Large Animal Surgery and Orthopaedics, Equine Clinic, University of Veterinary Medicine, Vienna, Austria.|Research Group Oncology, Equine Clinic, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Edmund K
authors.initials: EK
authors.lastname: Hainisch
authors.affiliation: Research Group Oncology, Equine Clinic, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Hans
authors.initials: H
authors.lastname: Abel-Reichwald
authors.affiliation: Laboratory of Viral Oncology, Division of Immunology, Allergy and Infectious Disease, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Saeed
authors.initials: S
authors.lastname: Shafti-Keramat
authors.affiliation: Research Group Oncology, Equine Clinic, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Barbara
authors.initials: B
authors.lastname: Pratscher
authors.affiliation: Institute of Protein Biochemistry, National Research Council of Italy, Naples, Italy.
authors.forename: Annunziata
authors.initials: A
authors.lastname: Corteggio
authors.affiliation: Department of Veterinary Medicine and Animal Productions, University of Naples Federico II, Naples, Italy.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Borzacchiello
authors.affiliation: Research Group Oncology, Equine Clinic, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Maria
authors.initials: M
authors.lastname: Wetzig
authors.affiliation: Research Group Oncology, Equine Clinic, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Christoph
authors.initials: C
authors.lastname: Jindra
authors.affiliation: Bioinformatics and Biostatistics Platform, Department of Biomedical Sciences, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Tichy
authors.affiliation: Laboratory of Viral Oncology, Division of Immunology, Allergy and Infectious Disease, Department of Dermatology, Medical University of Vienna, Vienna, Austria.
authors.forename: Reinhard
authors.initials: R
authors.lastname: Kirnbauer
authors.affiliation: Research Group Oncology, Equine Clinic, University of Veterinary Medicine, Vienna, Austria.
authors.forename: Sabine
authors.initials: S
authors.lastname: Brandt
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage; D000818:Animals; D052688:Bovine papillomavirus 1 / Q000276:immunology* / Q000302:isolation & purification; D004279:DNA, Viral / Q000276:immunology / Q000302:isolation & purification; D004195:Disease Models, Animal; D006734:Horse Diseases / Q000276:immunology / Q000517:prevention & control* / Q000821:virology; D006736:Horses; D000071497:Immunogenicity, Vaccine; D030361:Papillomavirus Infections / Q000517:prevention & control / Q000662:veterinary*; D012507:Sarcoidosis / Q000517:prevention & control / Q000662:veterinary*; D012871:Skin Diseases / Q000517:prevention & control / Q000662:veterinary*; D014611:Vaccination / Q000662:veterinary*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology*; D014771:Virion / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D004279:DNA, Viral; D014765:Viral Vaccines