title: Comparative efficacy of immunization with inactivated whole tachyzoites versus a tachyzoite-bradyzoite mixture against neosporosis in mice.
abstract: The worldwide economic impact of Neospora caninum infection has caused the development of effective vaccines to become one of the main goals in the field of neosporosis research. In this study, the protection conferred by antigens from inactivated whole tachyzoites (TZ) and a tachyzoite-bradyzoite mixture (TZ-BZ) of N. caninum (Nc-Spain7 isolate) incorporated into a water-in-oil emulsion (W/O) and aluminium hydroxide-ginseng extract (Al/G) was evaluated in mouse models of congenital and cerebral N. caninum infection. Immunization with TZ-BZ induced congenital and cerebral neosporosis exacerbation that was mainly characterized by reduced neonatal median survival time and increased parasite presence in adult mouse brains. The immune response of mice immunized with TZ-BZ was characterized by an increase in IFN-γ expression prior to challenge and an increase in IL-4 expression accompanied with significantly higher levels of antibodies against 2 recombinant bradyzoite-specific proteins (rNcSAG4 and rNcBSR4) after challenge. Immunization with TZ in W/O significantly reduced neonatal mortality, vertical transmission as well as parasite presence in adult mouse brains and induced a strong humoral immune response. The current study demonstrates the critical role of stage-specific antigens and adjuvants on the development of effective inactivated vaccines for the prevention of N. caninum infection.
authors.affiliation: SALUVET, Animal Health Department, Faculty of Veterinary Sciences, Complutense University of Madrid, Ciudad Universitaria s/n, 28040 Madrid, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Rojo-Montejo
authors.forename: E
authors.initials: E
authors.lastname: Collantes-Fernández
authors.forename: S
authors.initials: S
authors.lastname: Rodríguez-Marcos
authors.forename: F
authors.initials: F
authors.lastname: Pérez-Zaballos
authors.forename: I
authors.initials: I
authors.lastname: López-Pérez
authors.forename: A
authors.initials: A
authors.lastname: Prenafeta
authors.forename: L M
authors.initials: LM
authors.lastname: Ortega-Mora
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage* / Q000737:chemistry; D000818:Animals; D000831:Animals, Newborn; D000913:Antibodies, Protozoan / Q000096:biosynthesis* / Q000276:immunology; D002417:Cattle; D003048:Coccidiosis / Q000276:immunology / Q000469:parasitology / Q000517:prevention & control*; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D056724:Immunity, Humoral / Q000187:drug effects; D007114:Immunization / Q000401:mortality; D018445:Infectious Disease Transmission, Vertical / Q000517:prevention & control; D007371:Interferon-gamma / Q000032:analysis / Q000096:biosynthesis; D015847:Interleukin-4 / Q000032:analysis / Q000096:biosynthesis; D008018:Life Cycle Stages / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D018688:Neospora / Q000276:immunology*; D016133:Polymerase Chain Reaction; D011247:Pregnancy; D016052:Protozoan Vaccines / Q000008:administration & dosage* / Q000276:immunology / Q000378:metabolism; D011994:Recombinant Proteins / Q000276:immunology / Q000378:metabolism; D015164:Vaccines, Inactivated / Q000008:administration & dosage* / Q000276:immunology / Q000378:metabolism
chemical_list: D000276:Adjuvants, Immunologic; D000913:Antibodies, Protozoan; D016052:Protozoan Vaccines; D011994:Recombinant Proteins; D015164:Vaccines, Inactivated; D015847:Interleukin-4; D007371:Interferon-gamma