title: The bovine viral diarrhea virus E2 protein formulated with a novel adjuvant induces strong, balanced immune responses and provides protection from viral challenge in cattle.
abstract: Bovine viral diarrhea virus (BVDV) is still one of the most serious pathogens in cattle, meriting the development of improved vaccines. Recently, we developed a new adjuvant consisting of poly[di(sodium carboxylatoethylphenoxy)]-phosphazene (PCEP), either CpG ODN or poly(I:C), and an immune defense regulator (IDR) peptide. As this adjuvant has been shown to mediate the induction of robust, balanced immune responses, it was evaluated in an E2 subunit vaccine against BVDV in lambs and calves. The BVDV type 2 E2 protein was produced at high levels in a mammalian expression system and purified. When formulated with either CpG ODN or poly(I:C), together with IDR and PCEP, the E2 protein elicited high antibody titers and production of IFN-γ secreting cells in lambs. As the immune responses were stronger when poly(I:C) was used, the E2 protein with poly(I:C), IDR and PCEP was subsequently tested in cattle. Robust virus neutralizing antibodies as well as cell-mediated immune responses, including CD8(+) cytotoxic T cell (CTL) responses, were induced. The fact that CTL responses were demonstrated in calves vaccinated with an E2 protein subunit vaccine indicates that this adjuvant formulation promotes cross-presentation. Furthermore, upon challenge with a high dose of virulent BVDV-2, the vaccinated calves showed almost no temperature response, weight loss, leukopenia or virus replication, in contrast to the control animals, which had severe clinical disease. These data suggest that this E2 subunit formulation induces significant protection from BVDV-2 challenge, and thus is a promising BVDV vaccine candidate; in addition, the adjuvant platform has applications in bovine vaccines in general.
authors.affiliation: VIDO-Intervac, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3.
authors.forename: Marlene
authors.initials: M
authors.lastname: Snider
authors.affiliation: VIDO-Intervac, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3.
authors.forename: Ravendra
authors.initials: R
authors.lastname: Garg
authors.affiliation: VIDO-Intervac, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3.
authors.forename: Robert
authors.initials: R
authors.lastname: Brownlie
authors.affiliation: VIDO-Intervac, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3.
authors.forename: Jan V
authors.initials: JV
authors.lastname: van den Hurk
authors.affiliation: VIDO-Intervac, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3; Microbiology and Immunology, University of Saskatchewan, Saskatoon, SK, Canada S7N 5E3. Electronic address: sylvia.vandenhurk@usask.ca.
authors.forename: Sylvia
authors.initials: S
authors.lastname: van Drunen Littel-van den Hurk
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage*; D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood; D000914:Antibodies, Viral / Q000097:blood; D002417:Cattle; D002418:Cattle Diseases / Q000473:pathology / Q000517:prevention & control*; D030242:Diarrhea Virus 2, Bovine Viral / Q000276:immunology*; D007371:Interferon-gamma / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000276:immunology; D018182:Pestivirus Infections / Q000473:pathology / Q000517:prevention & control / Q000662:veterinary*; D012756:Sheep; D012757:Sheep Diseases / Q000473:pathology / Q000517:prevention & control*; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology; D022223:Vaccines, Subunit / Q000008:administration & dosage / Q000276:immunology; D014759:Viral Envelope Proteins / Q000276:immunology*; D014765:Viral Vaccines / Q000008:administration & dosage / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D057134:Antibodies, Neutralizing; D000914:Antibodies, Viral; D022223:Vaccines, Subunit; D014759:Viral Envelope Proteins; D014765:Viral Vaccines; C076551:gp53, bovine viral diarrhea virus; D007371:Interferon-gamma
keywords: Bovine viral diarrhea virus; E2 subunit vaccine; Novel adjuvant; Protection; cattle