title: Comparative evaluation of immunization with recombinant protein and plasmid DNA vaccines of fusion antigen ROP2 and SAG1 from Toxoplasma gondii in mice: cellular and humoral immune responses.
abstract: The aim of this work was to evaluate immune responses in BALB/c mice vaccinated subcutaneously by recombinant protein, or intramuscularly by plasmid DNA with fusion antigen of rhoptry protein 2 (ROP2) and major surface protein 1 (SAG1) from Toxoplasma gondii (T. gondii). BALB/c mice were immunized with one of three different antigen formulations respectively, which were rROP2-SAG1, pcROP2-SAG1, and pcROP2-SAG1 boosted with rROP2-SAG1. The production of IgG, IgG subclasses, lymphoproliferation, and level of gamma interferon (IFN-γ) were detected after vaccination. The animals vaccinated with rROP2-SAG1 quickly developed specific anti-TLA (T. gondii lysate antigen) antibodies, which continued to rise after immunization. However, production of IgG against TLA in mice vaccinated with pcROP2-SAG1 was relatively slow and maintained a high level after reaching plateau. There are more vigorous specific lymphoproliferative responses observed in mice of group rROP2-SAG1 than in pcROP2-SAG1. Immune responses in mice of group pcROP2-SAG1 boosted with rROP2-SAG1 were similar to the protein immunization group. Three immunization procedures resulted in a similar level of IFN-γ production. Our results indicate that BALB/c mice vaccinated by three immunization procedures induce similar humoral and cellular immunity against infection of T. gondii. Mice immunized with recombinant protein rROP2-SAG1 produce more humoral immune responses than mice immunized with other antigen formulations.
authors.affiliation: Department of Microbiology and Immunology, Wenzhou Medical College, Wenzhou 325035, Zhejiang Province, China.
authors.forename: Wen-Shu
authors.initials: WS
authors.lastname: Li
authors.forename: Qing-Xin
authors.initials: QX
authors.lastname: Chen
authors.forename: Ju-Xiu
authors.initials: JX
authors.lastname: Ye
authors.forename: Zi-Xin
authors.initials: ZX
authors.lastname: Xie
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.forename: Li-Fang
authors.initials: LF
authors.lastname: Zhang
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D049109:Cell Proliferation; D005260:Female; D007074:Immunoglobulin G / Q000097:blood; D007273:Injections, Intramuscular; D007279:Injections, Subcutaneous; D007371:Interferon-gamma / Q000378:metabolism; D007963:Leukocytes, Mononuclear / Q000276:immunology; D008565:Membrane Proteins / Q000235:genetics / Q000276:immunology*; D051379:Mice; D008807:Mice, Inbred BALB C; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D011994:Recombinant Proteins / Q000235:genetics / Q000276:immunology; D014122:Toxoplasma / Q000235:genetics / Q000276:immunology*; D014611:Vaccination / Q000379:methods*; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D007074:Immunoglobulin G; D008565:Membrane Proteins; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; C090555:ROP 2 protein, Toxoplasma gondii; D011994:Recombinant Proteins; C047168:SAG1 antigen, Toxoplasma; D019444:Vaccines, DNA; D014614:Vaccines, Synthetic; D007371:Interferon-gamma