title: Saccharomyces boulardii improves humoral immune response to DNA vaccines against leptospirosis.
abstract: OBJECTIVE
  Saccharomyces boulardii may improve the immune response by enhancing the production of anti-inflammatory cytokines, T-cell proliferation and dendritic cell activation. The immunomodulator effect of this probiotic has never been tested with DNA vaccines, which frequently induce low antibody titers. This study evaluated the capacity of Saccharomyces boulardii to improve the humoral and cellular immune responses using DNA vaccines coding for the leptospiral protein fragments LigAni and LigBrep. BALB/c mice were fed with rodent-specific feed containing 108 c.f.u. of Saccharomycesboulardii per gram.
  
  
  METHODS
  Animals were immunized three times intramuscularly with 100 µg of pTARGET plasmids containing the coding sequences for the above mentioned proteins. Antibody titers were measured by indirect ELISA. Expression levels of IL-4, IL-10, IL-12, IL-17, IFN-γ and TGF-β were determined by quantitative real-time PCR from RNA extracted from whole blood, after an intraperitoneal boost with 50 µg of the recombinant proteins.Results/Key findings. Antibody titers increased significantly after the second and third application when pTARGET/ligAni and pTARGET/ligBrep were used to vaccinate the animals in comparison with the control group (P<0.05). In addition, there was a significant increase in the expression of the IL-10 in mice immunized with pTARGET/ligBrep and fed with Saccharomyces boulardii.
  
  
  CONCLUSIONS
  The results suggested that Saccharomyces boulardii has an immunomodulator effect in DNA vaccines, mainly by stimulating the humoral response, which is often limited in this kind of vaccine. Therefore, the use of Saccharomyces boulardii as immunomodulator represents a new alternative strategy for more efficient DNA vaccination.
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Marcelle Moura
authors.initials: MM
authors.lastname: Silveira
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Fabricio Rochedo
authors.initials: FR
authors.lastname: Conceição
authors.affiliation: Curso de Medicina Veterinária, Universidade Federal Rural de Pernambuco, Unidade Acadêmica de Garanhuns, Avenida Bom Pastor, S/N, Boa Vista, 55292-270 Garanhuns, PE, Brazil.|Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Marcelo
authors.initials: M
authors.lastname: Mendonça
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Gustavo Marçal Schmidt Garcia
authors.initials: GMSG
authors.lastname: Moreira
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Carlos Eduardo Pouey
authors.initials: CEP
authors.lastname: Da Cunha
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Neida Lucia
authors.initials: NL
authors.lastname: Conrad
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Patrícia Diaz de
authors.initials: PD
authors.lastname: Oliveira
authors.affiliation: Departamento de Microbiologia e Parasitologia, Instituto de Biologia, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.|Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Daiane Drawanz
authors.initials: DD
authors.lastname: Hartwig
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.
authors.forename: Priscila Marques Moura
authors.initials: PMM
authors.lastname: De Leon
authors.affiliation: Programa de Pós-Graduação em Biotecnologia, Centro de Desenvolvimento Tecnológico, Universidade Federal de Pelotas, Campus Universitário S/N, Caixa Postal 354, 96010-900 Pelotas, RS, Brazil.|Departamento de Nutrição, Faculdade de Nutrição, Universidade Federal de Pelotas, Campus Porto/Anglo, Rua Gomes Carneiro, 01 - Centro, Caixa Postal 354, 96010-610 Pelotas, RS, Brazil.
authors.forename: Ângela Nunes
authors.initials: ÂN
authors.lastname: Moreira
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D001428:Bacterial Vaccines / Q000276:immunology*; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D005260:Female; D056724:Immunity, Humoral; D007155:Immunologic Factors / Q000276:immunology; D007919:Leptospira; D007922:Leptospirosis / Q000276:immunology* / Q000517:prevention & control; D051379:Mice; D008807:Mice, Inbred BALB C; D019936:Probiotics / Q000008:administration & dosage; D011994:Recombinant Proteins / Q000235:genetics; D000069983:Saccharomyces boulardii; D019444:Vaccines, DNA / Q000276:immunology*
chemical_list: D001426:Bacterial Proteins; D001428:Bacterial Vaccines; D016207:Cytokines; D007155:Immunologic Factors; D011994:Recombinant Proteins; D019444:Vaccines, DNA