title: Protective immunity induced by a recombinant BCG vaccine encoding the cyclophilin gene of Toxoplasma gondii.
abstract: The investigation of Toxoplasma gondii virulence factors can elucidate the immunopathology of T. gondii infection and identify potential candidates for effective human vaccines. The adjuvant is an important component of an effective vaccine. In this study, attenuated Mycobacterium bovis was used as a live vaccine vector with both antigen and adjuvant characteristics. Following amplification of the T. gondii cyclophilin gene, the shuttle expression plasmid pMV261-TgCyP and integrative expression plasmid pMV361-TgCyP were constructed, and their expression was stimulated after transfection into BCG. Both recombinant plasmids were highly immunogenic. Greater proliferation of CD4(+) and CD8(+) T cells was observed in the rBCG-vaccinated groups compared to the control groups. The levels of Th1-type IFN-γ, IL-2 and IL-12 were significantly increased following immunisation with the rBCG vaccines via the i.v. or oral route, which indicated that catalytic activity against T. gondii infection was generated in the mice. rBCGpMV361-TgCyP i.v. inoculation resulted in a higher protection efficiency, as demonstrated by the increased survival time and survival rate (17%) of BALB/c mice. The present study demonstrates that a BCG vector expressing a target antigen, TgCyP, represent an alternative system for the production of effective vaccines to prevent toxoplasmosis.
authors.affiliation: Institute of Zoonosis, College of Veterinary Medicine, Jilin University, 5333 Xi'an Road, Changchun 130062, China; Jilin Provincial Animal Disease Control Center, 4510 Xi'an Road, Changchun 130062</postal>, China.
authors.forename: Qinlei
authors.initials: Q
authors.lastname: Yu
authors.forename: Xiangsheng
authors.initials: X
authors.lastname: Huang
authors.forename: Pengtao
authors.initials: P
authors.lastname: Gong
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhang
authors.forename: Jianhua
authors.initials: J
authors.lastname: Li
authors.forename: Guocai
authors.initials: G
authors.lastname: Zhang
authors.forename: Ju
authors.initials: J
authors.lastname: Yang
authors.forename: He
authors.initials: H
authors.lastname: Li
authors.forename: Nan
authors.initials: N
authors.lastname: Wang
authors.forename: Xichen
authors.initials: X
authors.lastname: Zhang
mesh_terms: D000818:Animals; D021983:Cyclophilins / Q000235:genetics / Q000276:immunology*; D004195:Disease Models, Animal; D004337:Drug Carriers; D005822:Genetic Vectors; D051379:Mice; D008807:Mice, Inbred BALB C; D009163:Mycobacterium bovis / Q000235:genetics*; D010957:Plasmids; D016052:Protozoan Vaccines / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology*; D016019:Survival Analysis; D014122:Toxoplasma / Q000235:genetics / Q000276:immunology*; D014124:Toxoplasmosis, Animal / Q000276:immunology / Q000517:prevention & control*; D014614:Vaccines, Synthetic / Q000008:administration & dosage / Q000235:genetics / Q000276:immunology
chemical_list: D004337:Drug Carriers; D016052:Protozoan Vaccines; D014614:Vaccines, Synthetic; D021983:Cyclophilins
keywords: BALB/c; Cyclophilin; T. gondii; rBCG