title: Induction of protective Th1 immune responses in mice by vaccination with recombinant Toxoplasma gondii nucleoside triphosphate hydrolase-II.
abstract: The Toxoplasma gondii nucleoside triphosphate hydrolase (TgNTPase) has apyrase activity, degrading ATP to the di- and mono-phosphate forms and may be used by the parasite to salvage purines from the host cell for survival and replication. To study the immune-protective value of TgNTPase-II, BALB/c mice were immunized with a recombinant form of the antigen rTgNTPase-II combined with alum. All immunized mice produced specific anti-rTgNTPase-II immunoglobulins, with high IgG antibody titers and a mixed IgG1/IgG2a response, with predominance of IgG2a production. The cellular immune response was associated with the production of IFN-γ and IL-2 cytokines and the increase of the percentage of CD8+ T cells. Vaccinated mice displayed significant protection against acute infection with the virulent RH strain (P<0.05 in survival rate) and also chronic infection with PRU cyst (62.9% and 57.6% reduction in brain parasite load for rTgNTPase-II+alum and rTgNTPase-II alone vaccinated groups) compared to the non-vaccinated control group. In conclusion, rTgNTPase-II elicits a strong specific Th1 immune response providing partial protection against both T. gondii acute and chronic infection.
authors.affiliation: Department of Parasitology, Southern Medical University, Guangzhou, Guangdong 510515, People's Republic of China.
authors.forename: Feng
authors.initials: F
authors.lastname: Tan
authors.forename: Xin
authors.initials: X
authors.lastname: Hu
authors.forename: Fang-Jun
authors.initials: FJ
authors.lastname: Luo
authors.forename: Chang-Wang
authors.initials: CW
authors.lastname: Pan
authors.forename: Xiao-Guang
authors.initials: XG
authors.lastname: Chen
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D001921:Brain / Q000469:parasitology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D004195:Disease Models, Animal; D005260:Female; D007074:Immunoglobulin G / Q000097:blood; D007371:Interferon-gamma / Q000378:metabolism; D007376:Interleukin-2 / Q000378:metabolism; D051379:Mice; D008807:Mice, Inbred BALB C; D043583:Nucleoside-Triphosphatase / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000276:immunology*; D016019:Survival Analysis; D018417:Th1 Cells / Q000276:immunology*; D014122:Toxoplasma / Q000201:enzymology* / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000276:immunology / Q000517:prevention & control*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000276:immunology
chemical_list: D000913:Antibodies, Protozoan; D007074:Immunoglobulin G; D007376:Interleukin-2; D016052:Protozoan Vaccines; D014614:Vaccines, Synthetic; D007371:Interferon-gamma; D043583:Nucleoside-Triphosphatase