title: Interferon-gamma expression and infectivity of Toxoplasma infected tissues in experimentally infected sheep in comparison with pigs.
abstract: Livestock animals are a potential risk for transmission of toxoplasmosis to humans. Sheep and pigs still remain an important source because their meat is often eaten undercooked which has been regarded as a major route of infection in many countries. Moreover, porcine tissues are processed in many food products. In the current study, the IFN-gamma (T-helper 1 cells), IL-4 (Th2 cells) and IL-10 mRNA (Treg cells) expression by blood mononuclear cells, and the serum antibody response against Toxoplasma gondii total lysate antigen, recombinant T. gondii GRA1, rGRA7, rMIC3 and rEC2, a chimeric antigen composed of MIC2, MIC3 and SAG1, was studied in sheep the first two months after a T. gondii infection and compared with these responses in pigs. At the end of this period, the parasite distribution in heart, brain and two skeletal muscles in sheep was compared with this in pigs. Whereas the parasite distribution was similar in sheep and pigs, the antibody response differed considerably. In sheep, antibodies appeared against all tested T. gondii antigens, but mainly against rGRA7, rMIC3234307 and TLA whereas in pigs only rGRA7-specific antibodies could be demonstrated. Also, the cytokine response differed. Both in sheep and pigs an IFN-gamma response occurred which seemed to be a slightly more pronounced in sheep. In sheep, also IL-10 and IL-4 mRNA expression showed an increase, but later than IFN-gamma and with more variation. However, in pigs no such increase was seen. As concerning diagnosis, results indicate that serum antibodies against GRA7 in live sheep and pigs and heart tissue for bioassay and qPCR in slaughtered animals are the best targets to demonstrate presence of T. gondii infection.
authors.affiliation: Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium.
authors.forename: D
authors.initials: D
authors.lastname: Verhelst
authors.affiliation: National Reference Laboratory for Toxoplasmosis, Operational Direction Communicable and Infectious Diseases, Scientific Institute of Public Health, Federal Public Service Public Health, Security of the Food chain and Environment, Brussels, Belgium.
authors.forename: S
authors.initials: S
authors.lastname: De Craeye
authors.affiliation: Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium.
authors.forename: M
authors.initials: M
authors.lastname: Jennes
authors.affiliation: Department of Biomedical Sciences, Institute for Tropical Medicine, Antwerp, Belgium; Laboratory of Parasitology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium.
authors.forename: P
authors.initials: P
authors.lastname: Dorny
authors.affiliation: Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium; Department of Biosystems, Faculty of Bioscience Engineering, K.U. Leuven, Belgium.
authors.forename: B
authors.initials: B
authors.lastname: Goddeeris
authors.affiliation: Laboratory of Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium. Electronic address: Eric.Cox@ugent.be.
authors.forename: E
authors.initials: E
authors.lastname: Cox
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood*; D000953:Antigens, Protozoan / Q000276:immunology; D001921:Brain / Q000469:parasitology; D016207:Cytokines / Q000235:genetics / Q000378:metabolism; D006321:Heart / Q000469:parasitology; D007371:Interferon-gamma / Q000235:genetics* / Q000378:metabolism; D016753:Interleukin-10 / Q000235:genetics / Q000378:metabolism; D018482:Muscle, Skeletal / Q000469:parasitology; D015800:Protozoan Proteins / Q000276:immunology; D011994:Recombinant Proteins; D012756:Sheep; D012757:Sheep Diseases / Q000276:immunology* / Q000469:parasitology; D013552:Swine; D013553:Swine Diseases / Q000276:immunology* / Q000469:parasitology; D014122:Toxoplasma / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000276:immunology* / Q000469:parasitology
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016207:Cytokines; D015800:Protozoan Proteins; D011994:Recombinant Proteins; D016753:Interleukin-10; D007371:Interferon-gamma
keywords: Antibody response; Cytokine response; Pigs; Sheep; Toxoplasma gondii infection