title: Induction of protective immunity by multiantigenic DNA vaccine delivered in attenuated Salmonella typhimurium against Toxoplasma gondii infection in mice.
abstract: Toxoplasma gondii, capable of infecting all warm blooded animals, is one of the most successful parasites worldwide. It was reported that the single-gene vaccine with SAG1 or MIC3 could only produce partial protection against T. gondii and multiantigenic vaccines were more effective than single ones. In the present study, a multiantigenic DNA vaccine delivered by attenuated Salmonella typhimurium (ZJ111/pSAG1-MIC3) was constructed, which expresses surface protein SAG1 and micronemal protein MIC3. The safety and stability of ZJ111/pSAG1-MIC3 were evaluated and immune response with ZJ111/pSAG1 and ZJ111/pMIC3 were compared. The results of lymphocyte proliferation assay, antibody and cytokine determination show that mice immunized with ZJ111/pSAG1-MIC3 elicited stronger humoral and Th1-type cellular immune responses than other groups. The mice immunized with ZJ111/pSAG1-MIC3 also exhibited significant higher survival time after challenged with T. gondii RH strain. The current study shows that the oral multiantigenic DNA vaccine, ZJ111/pSAG1-MIC3, produces partial protection against T. gondii challenge.
authors.affiliation: Key Laboratory of Animal Epidemic Etiology and Immunological Prevention of Ministry of Agriculture, Zhejiang University, Hangzhou 310029, China.
authors.forename: Daofeng
authors.initials: D
authors.lastname: Qu
authors.forename: Haijie
authors.initials: H
authors.lastname: Yu
authors.forename: Suhua
authors.initials: S
authors.lastname: Wang
authors.forename: Weiming
authors.initials: W
authors.lastname: Cai
authors.forename: Aifang
authors.initials: A
authors.lastname: Du
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D000953:Antigens, Protozoan / Q000276:immunology; D049109:Cell Proliferation; D016207:Cytokines / Q000276:immunology; D005260:Female; D007074:Immunoglobulin G / Q000097:blood; D008214:Lymphocytes / Q000166:cytology / Q000276:immunology; D051379:Mice; D008813:Mice, Inbred ICR; D015800:Protozoan Proteins / Q000276:immunology; D016052:Protozoan Vaccines / Q000276:immunology*; D012486:Salmonella typhimurium / Q000235:genetics / Q000502:physiology; D016019:Survival Analysis; D013997:Time Factors; D014122:Toxoplasma / Q000276:immunology*; D014123:Toxoplasmosis / Q000276:immunology / Q000401:mortality / Q000517:prevention & control*; D019444:Vaccines, DNA / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D000953:Antigens, Protozoan; D016207:Cytokines; D007074:Immunoglobulin G; C421382:MIC3 protein, Toxoplasma gondii; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; C047168:SAG1 antigen, Toxoplasma; D019444:Vaccines, DNA