title: A vaccine based on a mutant transferrin binding protein B of Haemophilus parasuis induces a strong T-helper 2 response and bacterial clearance after experimental infection.
abstract: This study aimed to characterize the type of immune response induced by an experimental vaccine based on a mutant Haemophilus parasuis transferrin binding protein (Tbp) B (Y167A) defective in its ability to bind porcine transferrin. Clinical and pathological signs, bacterial clearance, antibody response and the cytokine profile in alveolar macrophages and spleen after the vaccination and challenge of twenty-two colostrum-deprived pigs with 10(8) CFU of H. parasuis were analysed. Pigs vaccinated with Y167A were compared to those vaccinated with native TbpB (nTbpB), those treated with a commercial bacterin (CB) against Glässer's disease, those unvaccinated challenged (CH) and those unvaccinated unchallenged (UNCH) pigs. The rectal temperatures of Y167A pigs resembled those of UNCH pigs and were significantly lower than those of the nTbpB, CB and CH animals. A major reduction in pathological changes of the challenged pigs was observed in the Y167A group. H. parasuis was cleared from 88.9% of the samples from Y167A pigs versus 60.0% and 55.6% from those of the CB and nTbpB groups, respectively. The antibody response elicited by Y167A by ELISA was notably higher than that observed for nTbpB and CB pigs and was capable of preventing the expression and secretion of IL-8. The expression of IL-4 and IL-5, which were associated with the specific antibody levels, suggests that the main mechanism of protection conferred by Y167A vaccine is based on a strong T-helper 2 response.
authors: Microbiology and Immunology Section, Department of Animal Health, Faculty of Veterinary Medicine, University of León, Spain.
authors: Sonia
authors: S
authors: Martínez-Martínez
authors: Microbiology and Immunology Section, Department of Animal Health, Faculty of Veterinary Medicine, University of León, Spain; Laboratory of Microbiology and Advanced Immunology, Faculty of Agronomy and Veterinary Medicine, University of Passo Fundo, Brazil.
authors: Rafael
authors: R
authors: Frandoloso
authors: Microbiology and Immunology Section, Department of Animal Health, Faculty of Veterinary Medicine, University of León, Spain.
authors: Elías-Fernando
authors: EF
authors: Rodríguez-Ferri
authors: Histology and Pathological Anatomy Section, Department of Animal Health, Faculty of Veterinary Medicine, University of León, Spain.
authors: María-José
authors: MJ
authors: García-Iglesias
authors: Histology and Pathological Anatomy Section, Department of Animal Health, Faculty of Veterinary Medicine, University of León, Spain.
authors: Claudia
authors: C
authors: Pérez-Martínez
authors: Microbiology and Immunology Section, Department of Animal Health, Faculty of Veterinary Medicine, University of León, Spain.
authors: Álvaro
authors: Á
authors: Álvarez-Estrada
authors: Microbiology and Immunology Section, Department of Animal Health, Faculty of Veterinary Medicine, University of León, Spain. Electronic address: cbgutm@unileon.es.
authors: César-Bernardo
authors: CB
authors: Gutiérrez-Martín
mesh_terms: D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D016207:Cytokines / Q000032:analysis; D006192:Haemophilus Infections / Q000276:immunology*; D018073:Haemophilus Vaccines / Q000276:immunology*; D044137:Haemophilus parasuis / Q000276:immunology*; D009154:Mutation; D013552:Swine; D013553:Swine Diseases / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*; D033882:Transferrin-Binding Protein B / Q000276:immunology*; D014611:Vaccination
chemical_list: D000907:Antibodies, Bacterial; D016207:Cytokines; D018073:Haemophilus Vaccines; D033882:Transferrin-Binding Protein B
keywords: Antibodies; Bacterial clearance; Cytokines; Glässer's disease; Haemophilus parasuis; Mutant TbpB vaccine