Protection against lethal Neospora caninum infection in mice induced by heterologous vaccination with a mic1-3 knockout Toxoplasma

Infect Immun. 2009 Dec 7. [Epub ahead of print]

Protection against lethal Neospora caninum infection in mice induced by heterologous vaccination with a mic1-3 knockout Toxoplasma gondii strain

Penarete Vargas DM, Mévélec MN, Dion S, Sèche E, Dimier-Poisson I, Fandeur T.

Université François-Rabelais de Tours, INRA, UMR 0483 Université-INRA d'Immunologie Parasitaire, Vaccinologie et Biothérapie Anti-Infectieuse, IFR des Agents Transmissibles et Infectiologie, UFR de Pharmacie, 31, Avenue Monge, 37200 Tours, France; VitamFero, UFR de Pharmacie, 31, Avenue Monge, 37200 Tours, France; Institut Pasteur, Unité d'Immunologie Moléculaire des Parasites - CNRS URA 2581 25, rue du Docteur-Roux, 75724 Paris cedex 15, France.

Neospora caninum and Toxoplasma gondii are closely related, obligate intracellular parasites infecting a wide range of vertebrate hosts and causing abortion and neonatal morbidity and mortality. Several lines of evidence suggest that cross immunity between these two pathogens could be exploited in the design of strategies for heterologous vaccination. We assessed the ability of an attenuated strain of T. gondii (mic1-3KO) conferring strong protection against chronic and congenital toxoplasmosis to protect mice against lethal N. caninum infection. Mice immunized with mic1-3KO tachyzoites, by the oral and intraperitoneal routes, developed a strong cellular Th1 response and displayed significant protection against lethal heterologous N. caninum infection, with survival rates of 70% and 80%, respectively; whereas only 30% of the non immunized mice survived. We report here the acquisition of heterologous protective immunity against N. caninum following immunization with a live attenuated mic1-3KO strain of T. gondii.

PMID: 19995895 [PubMed - as supplied by publisher]