title: Vaccination with a BCG strain overexpressing Ag85B protects cattle against Mycobacterium bovis challenge.
abstract: Mycobacterium bovis is the causative agent of tuberculosis in cattle but also infects other animals, including humans. Previous studies in cattle have demonstrated that the protection induced by BCG is not complete. In order to improve the protection efficacy of BCG, in this study we overexpressed Ag85B in a BCG Pasteur strain, by using an expression system based on the use of an auxotrophic strain for the leucine amino acid, and complementation with leuD. We found that vaccination of cattle with BCG overexpressing Ag85B induced higher production of IL-17 and IL-4 mRNA upon purified protein derivative (PPDB) stimulation of peripheral blood mononuclear cells (PBMCs) than vaccination with BCG. Moreover, the IL-17 mRNA expression after vaccination negatively correlated with disease severity resulting from a subsequent challenge with M. bovis, suggesting that this cytokine is a potential biomarker of cattle protection against bovine tuberculosis. Importantly, vaccination with the recombinant BCG vaccine protected cattle better than the wild-type BCG Pasteur.
authors.affiliation: Núcleo de Biotecnologia, CDTec, Universidade Federal de Pelotas, Pelotas, Brazil.
authors.forename: Caroline
authors.initials: C
authors.lastname: Rizzi
authors.forename: María Verónica
authors.initials: MV
authors.lastname: Bianco
authors.forename: Federico Carlos
authors.initials: FC
authors.lastname: Blanco
authors.forename: Marcelo
authors.initials: M
authors.lastname: Soria
authors.forename: María José
authors.initials: MJ
authors.lastname: Gravisaco
authors.forename: Valeria
authors.initials: V
authors.lastname: Montenegro
authors.forename: Lucas
authors.initials: L
authors.lastname: Vagnoni
authors.forename: Bryce
authors.initials: B
authors.lastname: Buddle
authors.forename: Sergio
authors.initials: S
authors.lastname: Garbaccio
authors.forename: Fernando
authors.initials: F
authors.lastname: Delgado
authors.forename: Karen Silva
authors.initials: KS
authors.lastname: Leal
authors.forename: Angel Adrián
authors.initials: AA
authors.lastname: Cataldi
authors.forename: Odir Antônio
authors.initials: OA
authors.lastname: Dellagostin
authors.forename: Fabiana
authors.initials: F
authors.lastname: Bigi
mesh_terms: D000818:Animals; D001500:BCG Vaccine / Q000008:administration & dosage*; D002417:Cattle; D002418:Cattle Diseases / Q000276:immunology / Q000517:prevention & control*; D017931:DNA Primers; D005434:Flow Cytometry; D007371:Interferon-gamma / Q000096:biosynthesis; D009163:Mycobacterium bovis / Q000276:immunology*; D016133:Polymerase Chain Reaction; D014374:Tuberculin Test; D014380:Tuberculosis, Bovine / Q000276:immunology / Q000517:prevention & control*
chemical_list: D001500:BCG Vaccine; D017931:DNA Primers; D007371:Interferon-gamma