title: Protective efficacy of two novel DNA vaccines expressing Toxoplasma gondii rhomboid 4 and rhomboid 5 proteins against acute and chronic toxoplasmosis in mice.
abstract: OBJECTIVE
  To evaluate the protective efficacy of two novel DNA vaccines expressing Toxoplasma gondii rhomboid 4 (ROM4) and rhomboid 5 (ROM5) proteins against acute and chronic toxoplasmosis.
  
  
  METHODS
  DNA vaccines (pVAX-TgROM5 and pVAX-TgROM4) were constructed and their immunogenicity evaluated in Kunming mice.
  
  
  RESULTS
  Mice vaccinated with pVAX-TgROM5 or pVAX-TgROM4 elicited strong Th1-type humoral and cellular responses, with higher level of IgG antibody titers (the predominance of IgG2a production), and increased levels of CD4(+) and CD8(+) T cells and cytokines IFN-γ, IL-2, IL-12 (p70) and IL-23. Mice vaccinated with pVAX-TgROM5 (11 days) showed a significantly longer survival time compared with controls (8 days) (p < 0.05) after lethal challenge. Brain cyst numbers of mice vaccinated with pVAX-TgROM5 and pVAX-TgROM4 reduced significantly (p < 0.05) (72.04 and 44.08%, respectively) compared with control groups after chronic challenge.
  
  
  CONCLUSIONS
  The pVAX-TgROM5 showed a better protective efficacy against acute and chronic toxoplasmosis compared to pVAX-TgROM4.
authors.affiliation: State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province 730046, PR China.
authors.forename: Nian-Zhang
authors.initials: NZ
authors.lastname: Zhang
authors.forename: Ying
authors.initials: Y
authors.lastname: Xu
authors.forename: Meng
authors.initials: M
authors.lastname: Wang
authors.forename: Eskild
authors.initials: E
authors.lastname: Petersen
authors.forename: Jia
authors.initials: J
authors.lastname: Chen
authors.forename: Si-Yang
authors.initials: SY
authors.lastname: Huang
authors.forename: Xing-Quan
authors.initials: XQ
authors.lastname: Zhu
mesh_terms: D000818:Animals; D000913:Antibodies, Protozoan / Q000097:blood; D001921:Brain / Q000469:parasitology / Q000473:pathology; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D018414:CD8-Positive T-Lymphocytes / Q000276:immunology; D016207:Cytokines / Q000378:metabolism; D004195:Disease Models, Animal; D005260:Female; D007074:Immunoglobulin G / Q000097:blood; D051379:Mice; D010447:Peptide Hydrolases / Q000235:genetics / Q000276:immunology*; D015800:Protozoan Proteins / Q000235:genetics / Q000276:immunology*; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D016019:Survival Analysis; D018417:Th1 Cells / Q000276:immunology; D014122:Toxoplasma / Q000235:genetics / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000517:prevention & control*; D016896:Treatment Outcome; D019444:Vaccines, DNA / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*
chemical_list: D000913:Antibodies, Protozoan; D016207:Cytokines; D007074:Immunoglobulin G; D015800:Protozoan Proteins; D016052:Protozoan Vaccines; D019444:Vaccines, DNA; D010447:Peptide Hydrolases; C560858:ROM4 protein, Toxoplasma gondii; C000598542:ROM5 protein, Toxoplasma gondii
keywords: DNA vaccine; ROM4; ROM5; Toxoplasma gondii; immune response; protective immunity