弓形虫P30-P22 DNA疫苗免疫小鼠诱导的细胞免疫应答

STUDY ON THE CELLULAR IMMUNE RESPONSES INDUCED BY DNA VACCINE WITH THE P30-P22 OF TOXOPLASMA GONDDI IN MICE

目的观察弓形虫P30-P22 DNA疫苗免疫小鼠后所诱导的细胞免疫应答。方法大量制备重组真核表达质粒pcDNA3.1-P30-P22,经肌内注射免疫BALB/C小鼠,初次免疫后,第2周和第4周各加强免疫1次。用MTT法测定免疫鼠脾脏T淋巴细胞转化率和NK细胞杀伤率,用免疫荧光法对CD4+、CD8+T细胞亚群进行测定。结果NK细胞杀伤率:实验组为(72.3±4.15)%,空质粒对照组和PBS对照组分别为(51.3±4.67)%和(47.4±5.10)%,实验组与两对照组之间比较差异有统计学意义(P<0.05),两对照组之间无统计学意义(P>0.05);ConA刺激淋巴细胞转化实验,实验组与对照组差异无显著性(P>0.05);对T淋巴细胞亚群进行分析,可见CD8+的数量上升,CD4+/CD8+的比率下降,实验组与对照组有明显差异(P<0.05)。结论弓形虫表面抗原P30-P22 DNA疫苗免疫BALB/c小鼠可诱导一定的细胞免疫应答。

Objective To observe the cell immune responses induced by P30-P22 DNA vaccine in mice. Methods Large-scale prepared recombinant plasmid pcDNA,3.1-P30-P22 was injected into the BALB/c mice via muscles. Two booster injections were given in the 2nd week and 4th week followed the first injection. The proliferation rate of lymopse cells and the killing activity of NK cells were tested by MTT assay, and T cell subgroup CD4 ＋ ,CD8 ＋ were tesed by the indirect immune fluorescent assay. Results The killing rate of the NK cells was higher than that of control group （ P 〈 0.05）, The proliferation rate spleen cell showed no difference between the test group and the control group （ P 〉0.05）.The result of kinetic analysis of CD4^＋ and CD8^＋ T cell subgroup showed that the number of CD8^ ＋ increased and the rate of CD4^＋/CD8 ^＋ reduced. There was remarkable difference between the controled mice and immunized ones（ P 〈 0.05 . Conclusion P30-P22 DNA vaccine could elicit cellular immune responses.