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

• Published in: Molecular and biochemical parasitology Vol. 153; no. 2; pp. 141 - 148
• Main Authors: Zhang, Houshuang, Lee, Eung-goo, Liao, Min, Compaore, Muller K.A., Zhang, Guohong, Kawase, Osamu, Fujisaki, Kozo, Sugimoto, Chihiro, Nishikawa, Yoshifumi, Xuan, Xuenan
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01.06.2007
• Subjects: Amino Acid Sequence; Animals; antibodies; Antibodies, Protozoan - blood; Antibodies, Protozoan - immunology; Antigens, Protozoan - immunology; Coccidiosis - parasitology; Coccidiosis - prevention & control; cross reaction; Cross Reactions; Cross-reactive; disease control; Gene Library; growth and development; growth inhibition; immunoglobulin G; immunolocalization; Mice; Molecular Sequence Data; Neospora - genetics; Neospora - growth & development; Neospora - immunology; Neospora - metabolism; Neospora caninum; neosporosis; phosphoproteins; Protozoan Vaccines - immunology; recombinant antigens; Recombinant Proteins - immunology; Ribosomal phosphoprotein P0; ribosomal proteins; Ribosomal Proteins - chemistry; Ribosomal Proteins - genetics; Ribosomal Proteins - immunology; Sequence Analysis, DNA; structural genes; tachyzoites; Toxoplasma - growth & development; Toxoplasma - immunology; Toxoplasma gondii; toxoplasmosis; Toxoplasmosis, Animal - parasitology; Toxoplasmosis, Animal - prevention & control; vaccine development; P0; Cross-reactive; Toxoplasma gondii; IFA; Neospora caninum; PAGE; Ribosomal phosphoprotein P0
• ISSN: 0166-6851; 1872-9428
• DOI: 10.1016/j.molbiopara.2007.02.012

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 936 bp, which encoded a protein of 311 amino acids. The NcP0 gene existed as a single copy in the genome and was interrupted by a 432 bp 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 34 kDa 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.