Vet. Res. 35 (2004) 225-232
DOI: 10.1051/vetres:2004005

Survival, immune responses and tissue cyst production in outbred (Swiss white) and inbred (CBA/Ca) strains of mice experimentally infected with Neospora caninum tachyzoites

Chantal Rettigner^a, Thierry Leclipteux^b, François De Meerschman^a, Charles Focant^a and Bertrand Losson<sup>a

a</sup>  Laboratory of Parasitology and Pathology of Parasitic Diseases, Department of Infectious and Parasitic Diseases, Faculty of Veterinary Medicine, University of Liège, Boulevard de Colonster, 20, 4000 Liège, Belgium
^b  Coris Bioconcept, Science Park-Cassiopée, Rue Phocas Lejeune, 30 Bte 9, 5032 Gembloux, Belgium

(Received 15 July 2003; accepted 9 October 2003)

Abstract - The present work compared inbred (CBA/Ca) and outbred (Swiss white) strains of mice for their capacity to cope with a Neospora caninum infection and to consistently produce tissue cysts. In each experiment Swiss white and CBA/Ca mice were given three different doses of NC-1 tachyzoites. Lymphoproliferative and humoral responses as well as cytokine production were evaluated eight weeks after infection (PI) whereas tissue cyst production and histopathology were assessed 4, 6 and 10 weeks PI in immunosuppressed mice. Tissue cysts were observed 10 weeks after infection only in CBA/Ca mice receiving the two highest inoculum doses. Furthermore this strain showed the highest specific lymphoproliferative response. A mixed cytokine response with elevated IFN- and fairly low IL-4 and IL-10 secretion was recorded. In both strains, no lesions were observed in the tissues of infected mice. This study indicates that CBA/Ca female mice infected with 5 × 10⁶ NC-1 tachyzoites represent a useful model for the study of specific maternal immune responses in pregnant animals.

Key words: Neospora caninum / immune response / resistance / cyst / mice

Corresponding author: Chantal Rettigner Chantal.Rettigner@ulg.ac.be

© INRA, EDP Sciences 2004