Immuno-efficacy of DNA vaccines encoding PLP1 and ROP18 against experimental Toxoplasma gondii infection in mice

摘要

We constructed a new plasmid pIRESneo/ROP18/PLP1 that was injected intramuscularly into Kunming mice to evaluate its immune efficacy. The immunized mice exhibited significantly increased serum IgG2a levels, lymphocyte counts and Thl-type cytokine (IL-2, IL-12 and IFN-gamma) levels. Moreover, the immunized mice exhibited longer survival times (44.7 +/- 2.1 days for ROP18/PLP1 and 47.2 +/- 2.9 days for ROP18/PLP1 + IL-18) and lower brain cyst burden (68.9% for ROP18/PLP1 and 72.4% for ROP18/PLP1 + IL-18) than control mice after T. gondii challenge. Our results demonstrate that the multiple-gene DNA vaccine including both ROP18 and PLP1 elicits greater protection against T gondii challenge and stronger immunogenicity than single-gene vaccines. (C) 2018 Elsevier Inc. All rights reserved.