title: Immunogenicity of a Multi-Epitope DNA Vaccine Encoding Epitopes from Cu-Zn Superoxide Dismutase and Open Reading Frames ofBrucella abortusin Mice.
abstract: Brucellosis is a bacterial zoonotic disease affecting several mammalian species that is transmitted to humans by direct or indirect contact with infected animals or their products. In cattle, brucellosis is almost invariably caused byBrucella abortus. Live, attenuatedBrucellavaccines are commonly used to prevent illness in cattle, but can cause abortions in pregnant animals. It is, therefore, desirable to design an effective and safer vaccine againstBrucella. We have used specificBrucellaantigens that induce immunity and protection againstB. abortus. A novel recombinant multi-epitope DNA vaccine specific for brucellosis was developed. To design the vaccine construct, we employed bioinformatics tools to predict epitopes present in Cu-Zn superoxide dismutase and in the open reading frames of the genomic island-3 (BAB1_0260, BAB1_0270, BAB1_0273, and BAB1_0278) ofBrucella. We successfully designed a multi-epitope DNA plasmid vaccine chimera that encodes and expresses 21 epitopes. This DNA vaccine induced a specific humoral and cellular immune response in BALB/c mice. It induced a typical T-helper 1 response, eliciting production of immunoglobulin G2a and IFN-γ particularly associated with the Th1 cell subset of CD4+T cells. The production of IL-4, an indicator of Th2 activation, was not detected in splenocytes. Therefore, it is reasonable to suggest that the vaccine induced a predominantly Th1 response. The vaccine induced a statistically significant level of protection in BALB/c mice when challenged withB. abortus2308. This is the first use of anin silicostrategy to a design a multi-epitope DNA vaccine againstB. abortus.
authors.affiliation: Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción , Concepción , Chile.
authors.forename: Emilia
authors.initials: E
authors.lastname: Escalona
authors.affiliation: Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción , Concepción , Chile.
authors.forename: Darwin
authors.initials: D
authors.lastname: Sáez
authors.affiliation: Laboratory of Molecular Immunology, Department of Microbiology, Faculty of Biological Sciences, Universidad de Concepción , Concepción , Chile.
authors.forename: Angel
authors.initials: A
authors.lastname: Oñate
keywords: Brucella abortus; Cu–Zn SOD; brucellosis; genomic island 3; multi-epitope DNA vaccine