Ribosomal phosphoprotein P0 of Neospora caninum as a potential common vaccine candidate

Mol Biochem Parasitol. 2007 Mar 4; [Epub ahead of print]

Identification of ribosomal phosphoprotein P0 of Neospora caninum as a potential common vaccine candidate for the control of both neosporosis and toxoplasmosis

Zhang H, Lee EG, Liao M, Compaore MK, Zhang G, Kawase O, Fujisaki K, Sugimoto C, Nishikawa Y, Xuan X.

National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Inada-cho, Obihiro, Hokkaido 080-8555, Japan.

The characterization of the cross-reactive antigens of two closely related apicomplexan parasites, Neospora caninum and Toxoplasma gondii, is important to elucidate the common mechanisms of parasite-host interactions. In this context, a gene encoding N. caninum ribosomal phosphoprotein P0 (NcP0) was identified by immunoscreening of a N. caninum tachyzoite cDNA expression library with antisera from mice immunized with T. gondii tachyzoites. The NcP0 was encoded by a gene with open reading frame of 936bp, which encoded a protein of 311 amino acids. The NcP0 gene existed as a single copy in the genome and was interrupted by a 432bp intron. The NcP0 showed 94.5% amino acid identity to T. gondii P0 (TgP0). Anti-recombinant NcP0 (rNcP0) sera recognized a native parasite protein with a molecular mass of 34kDa in Western blot analysis. Immunofluorescence analysis showed that the NcP0 was localized to the surface of N. caninum tachyzoites. A purified anti-rNcP0 IgG antibody inhibited the growth of N. caninum and T. gondii in vitro in a concentration-dependent manner. These results indicate that P0 is a cross-reactive antigen between N. caninum and T. gondii and a potential common vaccine candidate to control both parasites.

PMID: 17412435 [PubMed - as supplied by publisher]