title: Protection of mice against the highly pathogenic VVIHD-Jby DNA and fowlpox recombinant vaccines, administered by electroporation and intranasal routes, correlates with serum neutralizing activity.
abstract: The control of smallpox was achieved using live vaccinia virus (VV) vaccine, which successfully eradicated the disease worldwide. As the variola virus no longer exists as a natural infection agent, mass vaccination was discontinued after 1980. However, emergence of smallpox outbreaks caused by accidental or deliberate release of variola virus has stimulated new research for second-generation vaccine development based on attenuated VV strains. Considering the closely related animal poxviruses that also arise as zoonoses, and the increasing number of unvaccinated or immunocompromised people, a safer and more effective vaccine is still required. With this aim, new vectors based on avian poxviruses that cannot replicate in mammals should improve the safety of conventional vaccines, and protect from zoonotic orthopoxvirus diseases, such as cowpox and monkeypox. In this study, DNA and fowlpox (FP) recombinants that expressed the VV L1R, A27L, A33R, and B5R genes were generated (4DNAmix, 4FPmix, respectively) and tested in mice using novel administration routes. Mice were primed with 4DNAmix by electroporation, and boosted with 4FPmix applied intranasally. The lethal VVIHD-Jstrain was then administered by intranasal challenge. All of the mice receiving 4DNAmix followed by 4FPmix, and 20% of the mice immunized only with 4FPmix, were protected. The induction of specific humoral and cellular immune responses directly correlated with this protection. In particular, higher anti-A27 antibodies and IFNγ-producing T lymphocytes were measured in the blood and spleen of the protected mice, as compared to controls. VVIHD-Jneutralizing antibodies in sera from the protected mice suggest that the prime/boost vaccination regimen with 4DNAmix plus 4FPmix may be an effective and safe mode to induce protection against smallpox and poxvirus zoonotic infections. The electroporation/intranasal administration routes contributed to effective immune responses and mouse survival.
authors.affiliation: Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133 Milano, Italy. Electronic address: massimiliano.bissa@nih.gov.
authors.forename: Massimiliano
authors.initials: M
authors.lastname: Bissa
authors.affiliation: Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Turin, Via Nizza 52, 10126 Torino, Italy. Electronic address: elena.quaglino@unito.it.
authors.forename: Elena
authors.initials: E
authors.lastname: Quaglino
authors.affiliation: Department of Medical Biotechnologies and Translational Medicine, University of Milan, Via Vanvitelli, 32, 20129 Milano, Italy. Electronic address: carlo.zanotto@unimi.it.
authors.forename: Carlo
authors.initials: C
authors.lastname: Zanotto
authors.affiliation: Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133 Milano, Italy. Electronic address: elena.illiano@unimi.it.
authors.forename: Elena
authors.initials: E
authors.lastname: Illiano
authors.affiliation: Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Turin, Via Nizza 52, 10126 Torino, Italy. Electronic address: valeria.rolih@unito.it.
authors.forename: Valeria
authors.initials: V
authors.lastname: Rolih
authors.affiliation: Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133 Milano, Italy. Electronic address: sol83@libero.it.
authors.forename: Sole
authors.initials: S
authors.lastname: Pacchioni
authors.affiliation: Department of Molecular Biotechnology and Health Sciences, Molecular Biotechnology Center, University of Turin, Via Nizza 52, 10126 Torino, Italy. Electronic address: federica.cavallo@unito.it.
authors.forename: Federica
authors.initials: F
authors.lastname: Cavallo
authors.affiliation: Department of Medical Biotechnologies and Translational Medicine, University of Milan, Via Vanvitelli, 32, 20129 Milano, Italy; Catholic University "Our Lady of Good Counsel", Rr. Dritan Hoxha, Tirana, Albania. Electronic address: carlo.degiulimorghen@unimi.it.
authors.forename: Carlo
authors.initials: C
authors.lastname: De Giuli Morghen
authors.affiliation: Department of Pharmacological and Biomolecular Sciences, University of Milan, Via Balzaretti, 9, 20133 Milano, Italy; Cellular and Molecular Pharmacology Section, National Research Council (CNR), Institute of Neurosciences, University of Milan, Via Vanvitelli, 32, 20129 Milano, Italy. Electronic address: antonia.radaelli@unimi.it.
authors.forename: Antonia
authors.initials: A
authors.lastname: Radaelli
mesh_terms: D000818:Animals; D057134:Antibodies, Neutralizing / Q000097:blood*; D018274:Electroporation; D005586:Fowlpox / Q000235:genetics*; D007111:Immunity, Cellular; D056724:Immunity, Humoral; D007371:Interferon-gamma / Q000097:blood / Q000276:immunology; D051379:Mice; D045908:Mpox, Monkeypox / Q000517:prevention & control; D009500:Neutralization Tests; D012899:Smallpox / Q000517:prevention & control; D012900:Smallpox Vaccine / Q000008:administration & dosage* / Q000235:genetics / Q000276:immunology; D014611:Vaccination / Q000379:methods*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology; D014616:Vaccinia virus / Q000235:genetics* / Q000472:pathogenicity; D014765:Viral Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D057134:Antibodies, Neutralizing; D012900:Smallpox Vaccine; D014614:Vaccines, Synthetic; D014765:Viral Vaccines; D007371:Interferon-gamma
keywords: Fowlpox virus; Intranasal mucosal vaccination; L1R, A27L, A33R, B5R VV genes; OPXV vaccine; Prime/boost; Recombinant vaccines