title: Protective effect of a prime-boost strategy with plasmid DNA followed by recombinant adenovirus expressing TgAMA1 as vaccines against Toxoplasma gondii infection in mice.
abstract: A heterologous prime-boost strategy with priming plasmid DNA followed by recombinant virus expressing relevant antigens is known to stimulate protective immunity against intracellular parasites. In this study, we have evaluated a heterologous prime-boost strategy for immunizing mice against Toxoplasma gondii infection. Our results revealed that the prime-boost strategy using both plasmid DNA and adenoviral vector encoding TgAMA1 may stimulate both humoral and Th1/Th2 cellular immune responses specific for TgAMA1. Moreover, C57BL/6 mice immunized with the pAMA1/Ad5Null, pNull/Ad5AMA1, and pAMA1/Ad5AMA1 constructs showed survival rates of 12.5%, 37.5%, and 50%, respectively. In contrast, all the pNull/Ad5Null immunized mice died after infection with the PLK-GFP strain of T. gondii. Brain cyst burden was reduced by 23% in mice immunized with pAMA1/Ad5AMA1 compared with the pNull/Ad5AMA1 immunized mice. These results demonstrate that the heterologous DNA priming and recombinant adenovirus boost strategy may provide protective immunity against T. gondii infection.
authors.affiliation: National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555, Japan.
authors.forename: Longzheng
authors.initials: L
authors.lastname: Yu
authors.forename: Junya
authors.initials: J
authors.lastname: Yamagishi
authors.forename: Shoufa
authors.initials: S
authors.lastname: Zhang
authors.forename: Chunmei
authors.initials: C
authors.lastname: Jin
authors.forename: Gabriel Oluga
authors.initials: GO
authors.lastname: Aboge
authors.forename: Houshuang
authors.initials: H
authors.lastname: Zhang
authors.forename: Guohong
authors.initials: G
authors.lastname: Zhang
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Tanaka
authors.forename: Kozo
authors.initials: K
authors.lastname: Fujisaki
authors.forename: Yoshifumi
authors.initials: Y
authors.lastname: Nishikawa
authors.forename: Xuenan
authors.initials: X
authors.lastname: Xuan
mesh_terms: D000256:Adenoviridae / Q000235:genetics; D000818:Animals; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D016054:DNA, Protozoan / Q000235:genetics / Q000302:isolation & purification; D005260:Female; D005786:Gene Expression Regulation; D005822:Genetic Vectors; D057809:HEK293 Cells; D006801:Humans; D051379:Mice; D008810:Mice, Inbred C57BL; D010957:Plasmids; D016052:Protozoan Vaccines / Q000235:genetics* / Q000276:immunology; D011994:Recombinant Proteins / Q000235:genetics / Q000378:metabolism; D058408:Th1-Th2 Balance; D014122:Toxoplasma / Q000235:genetics / Q000254:growth & development / Q000276:immunology; D014123:Toxoplasmosis / Q000276:immunology* / Q000517:prevention & control*; D014611:Vaccination / Q000379:methods*
chemical_list: C506564:AMA1 protein, Toxoplasma gondii; D000953:Antigens, Protozoan; D016054:DNA, Protozoan; D016052:Protozoan Vaccines; D011994:Recombinant Proteins