title: Evaluation of protective effect of multi-epitope DNA vaccine encoding six antigen segments of Toxoplasma gondii in mice.
abstract: To investigate the vaccine potential of multi-epitope vaccines against toxoplasmosis, a multi-epitope DNA vaccine, eukaryotic plasmid pcDNA3.1/T-ME expressing six antigen segments (SAG1(238-256), SAG1(281-320), GRA1(170-193), GRA4(331-345), GRA4(229-245), and GRA2(171-185)) of Toxoplasma gondii was constructed. We investigated the efficacy of pcDNA3.1/T-ME with or without co-administration of a CpG-oligodeoxynucleotide (CpG-ODN) as an adjuvant to protect mice (BALB/c and C57BL/6) against toxoplasmosis. High survival rates were observed in mice immunized with pcDNA3.1/T-ME when challenged with T. gondii RH strain. Lymphocyte proliferation assays, cytokine, and antibody determinations show that mice immunized with pcDNA3.1/T-ME produced stronger humoral and Th1-type cellular immune responses compared to untreated mice or those immunized with empty plasmids. However, co-immunization with CpG-ODN resulted in impaired immune responses. Our data demonstrates that multi-epitope DNA vaccination is a potential strategy for the control of toxoplasmosis and paves the way for further investigations into producing a multi-epitope anti-T. gondii DNA vaccine.
authors.affiliation: Department of Immunology and Microbiology, Xi'an Jiaotong University, China.
authors.forename: Shan
authors.initials: S
authors.lastname: Liu
authors.forename: Lin
authors.initials: L
authors.lastname: Shi
authors.forename: Yan-bin
authors.initials: YB
authors.lastname: Cheng
authors.forename: Gui-xiang
authors.initials: GX
authors.lastname: Fan
authors.forename: Hui-xun
authors.initials: HX
authors.lastname: Ren
authors.forename: Yu-kang
authors.initials: YK
authors.lastname: Yuan
mesh_terms: D000276:Adjuvants, Immunologic / Q000008:administration & dosage / Q000494:pharmacology; D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000235:genetics / Q000276:immunology*; D049109:Cell Proliferation; D016207:Cytokines / Q000378:metabolism; D000939:Epitopes / Q000235:genetics / Q000276:immunology*; D005822:Genetic Vectors; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D009838:Oligodeoxyribonucleotides / Q000008:administration & dosage / Q000494:pharmacology; D010957:Plasmids; D016052:Protozoan Vaccines / Q000235:genetics / Q000276:immunology*; D016019:Survival Analysis; D013601:T-Lymphocytes / Q000276:immunology; D014122:Toxoplasma / Q000235:genetics / Q000276:immunology*; D014123:Toxoplasmosis / Q000517:prevention & control*; D019444:Vaccines, DNA / Q000235:genetics / Q000276:immunology*
chemical_list: D000276:Adjuvants, Immunologic; D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; C408982:CPG-oligonucleotide; D016207:Cytokines; D000939:Epitopes; D009838:Oligodeoxyribonucleotides; D016052:Protozoan Vaccines; D019444:Vaccines, DNA