Evaluation of biological behaviour of atypical Toxoplasma gondii isolates

PARDINI, L.; BERNSTEIN, M.; CAMPERO, L.M.; MORÉ, G.; UNZAGA, J.M.; VENTURINI, M.C.

Conferencia; 26th International Conference of the World Association for the Advancement of Veterinary Parasitology (WAAVP 2017); 2017

WAAVP

Toxoplasma gondii infection in animals and humans is mainly chronic and asymptomatic, however during pregnancy or immunosuppression it can produce severe lesions. The aim of this study was to evaluate the biological behaviour of two atypical isolates obtained from chickens from Argentina using a mouse model. Four groups of nine Swiss mice were inoculated with three doses (100, 103 and 104 parasites/mouse) of Beverley strain (reference genotype II), C24 (genotype #123 at TOXODB) and 11/9gall (genotype #19) isolates and PBS as negative control. Animals were daily observed and mortality was recorded (acute infection considered as death within 7-15 dpi). Blood was taken at acute and chronic (30 dpi) infection for IgG detection by IFAT. Histopathological lesions were evaluated on brains stained with H&E. ANOVA, Kruskal-Wallis, and Dunn?s Multiple Range tests were used for statistical analysis (GraphPad Prism 5.0). Statistical significance for all analysis was established with P < 0.05. The isolate 11/9gall produced higher mortality (89%) than Beverley and C24 (55%), and no differences among doses were observed. Antibodies were detected in lower concentration in 11/9gall infected mice probably due to the acute mortality. Beverley strain induced significant major inflammatory response on acute infection (congestion, gliosis and perivascular mononuclear cuffings) than 11-9gall (P< 0.0001, Kruskal Wallis). It is important to analyse the interaction between the immune response and atypical T. gondii isolates to improve the mouse model for animals and humans toxoplasmosis.