Toxoplasma gondii is an obligate intracellular parasite, which is responsible for a widely distributed zoonosis. Effective vaccines against toxoplasmosis are necessary to protect the public health. The aim of this study is to evaluate the immune efficacy of DNA vaccines encoding TgMIC5 and TgMIC16 genes against T. gondii infection. The recombinant plasmid pVAX-MIC5 and pVAX-MIC16 were constructed and injected intramuscularly in mice. The specific immune responses and protection against challenge with T. gondii RH tachyzoites were evaluated by measuring the cytokine levels, serum antibody concentrations, lymphocyte proliferation, lymphocyte populations, and the survival time. The protection against challenge with the T. gondii RH tchyzoites and PRU cysts was examined by evaluation of the reduction in the brain cyst burden. The results indicated that immunized mice showed significantly increased levels of IgG, IFN-γ, IL-2, IL-12p70, and IL-12p40 and percentages of CD4⁺ and CD8⁺ T cells. Additionally, vaccination prolonged the mouse survival time and reduced brain cysts compared with controls. Mouse groups immunized with a two-gene cocktail of pVAX-MIC5 + pVAX-MIC16 were more protected than mouse groups immunized with a single gene of pVAX-MIC5 or pVAX-MIC16. These results demonstrate that TgMIC5 and TgMIC16 induce effective immunity against toxoplasmosis and may serve as a good vaccine candidate against T. gondii infection.

弓形虫是一种专性细胞内寄生虫，是广泛分布的人畜共患病的罪魁祸首。有效的弓形虫疫苗对于保护公众健康是必要的。本研究的目的是评估编码 TgMIC5 和 TgMIC16 基因的 DNA 疫苗的免疫效力。刚地弓形虫感染。构建重组质粒pVAX-MIC5和pVAX-MIC16，并进行小鼠肌肉注射。特异性免疫反应和针对攻击的保护刚地弓形虫通过测量细胞因子水平、血清抗体浓度、淋巴细胞增殖、淋巴细胞数量和存活时间来评估 RH 速殖子。对抗挑战的保护刚地弓形虫通过评估脑囊肿负荷的减少来检查 RH 裂殖子和 PRU 囊肿。结果表明，免疫小鼠的 IgG、IFN-γ、IL-2、IL-12p70 和 IL-12p40 水平以及 CD4 ⁺和 CD8 ⁺ T 细胞的百分比显着增加。此外，与对照组相比，疫苗接种延长了小鼠的存活时间并减少了脑囊肿。用 pVAX-MIC5 + pVAX-MIC16 的双基因混合物免疫的小鼠组比用 pVAX-MIC5 或 pVAX-MIC16 的单基因免疫的小鼠组受到更多的保护。这些结果表明 TgMIC5 和 TgMIC16 可诱导有效的弓形虫免疫，并可作为一种良好的候选疫苗刚地弓形虫 感染。