猪囊尾蚴DNA疫苗pVAX1/TSOL18的安全性评估

SAFETY EVALUATION OF DNA VACCINE PVAX1/TSOL18 AGAINST CYSTICERCUS CELLULOSAE

目的探讨pVAX1/TSOL18重组表达质粒作为DNA疫苗在小鼠体内的组织分布和生物安全性。方法将pVAX1/TSOL18重组质粒经肌肉注射免疫昆明系小鼠,免疫后在不同时间剖杀小鼠,分别采集心、肝、脾等组织样品,抽提gDNA,利用PCR技术分析pVAX1/TSOL18在组织内的分布及残留时间。同时,以PCR技术检测免疫动物粪便,分析pVAX1/TSOL18重组表达质粒在外界环境中的释放情况。结果免疫pVAX1/TSOL18重组表达质粒后1 d和5 d,在小鼠组织gDNA均扩增出目的片段,不同个体小鼠,扩增出目的片段的组织也不完全相同,但在血液中均扩增出了目的片段,d5较d1扩增出的目的片段明显变暗。免疫后15 d,仅在一只小鼠的血液中检测到TSOL18基因;免疫后30 d在所有动物组织中均未检测到重组表达质粒。同时,免疫1 d、5 d小鼠的粪便中均未检测到TSOL18基因。结论pVAX1/TSOL18重组表达质粒作为疫苗对动物和环境是安全的。

Objective The biosafety and tissue distribution of recombinant expression plasmid pVAX1/ TSOL18, an anti-cysticercosis DNA vaccine, was investigated in mice. Methods Recombinant pVAX1/TSOL18 plasmid was intramuscularly injected on the legs of mice, which were killed after 1 d, 5 d, 15 d and 30 d post-injection and the gDNA were extracted from hearts,liver,spleen, etc. at the different time. The distribution and the residual time of recombinant pVAX1/TSOL18 plasmids in the tissue of mice were analyzed by PCR technology. At the same time, the feces of mice were tested by PCR to investigate the release of pVAX1/TSOL18 in the external environment. Results One day and five days after immunization, the target fragments were amplified from the different gDNA of mice tissues. To the different individual, the tissue are also different which the target fragment were amplified from, but from blood of all the injected mice, the target fragment were obtained. Contrast to the result on the first day, the fragment are darker than that on the fifth days. Fifteen days after immunization, there was only one mouse in which the fragment of plasmid TSOL18 gene could be detected. Thirty days later, no any recombinant plasmid could be detected in all the mice. And the TSOL18 plasmid gene were not detected at the first and fifth day in the feces. Conclusion Recombinant plasmid pVAX1/TSOL18 is safe to mice and the surrounding environment as a vaccine.