IL-6和B7双基因转染的小鼠EL-4肿瘤细胞诱导抗肿瘤免疫作用

目的:探讨IL-6和B7双基因转染的小鼠肿瘤疫苗是否具有协同的抗肿瘤效应.方法:利用含小鼠B7分子和人IL-6分子cDNA的逆转录病毒载体pLmB7SN和pLhIL-6SN分别转染包装细胞株CRIP,经G418抗性筛选后以含有B7或IL-6外源基因的病毒颗粒感染小鼠EL-4胸腺瘤细胞,观察EL-4-IL-6、EL-4-B7、EL-4-IL-6+B7细胞在同基因宿主体内的致瘤性及作为抗肿瘤疫苗的能力.结果:相对亲本肿瘤细胞EL-4而言,单基因和双基因转染的EL-4细胞在小鼠体内的生长速度均明显减慢,小鼠存活时间均有一定延长,3种转基因的EL-4细胞经X-射线灭活后免疫小鼠,虽均未能阻止随后接种的EL-4细胞的生长,但小鼠存活时间都明显延长,IL-6和B7双基因转染的EL-4肿瘤细胞在抗肿瘤活性方面与IL-6或B7单基因转染的EL-4细胞差异无显著性.结论:与单基因表达疫苗比较,双基因表达疫苗没有表现出协同的抗肿瘤效应.

The anti-tumor effect of murine EL-4 tumor cells transfected with both of B7 and IL-6 gene

Objective: To explore whether co expression of IL 6 and B7 in EL 4 tumor cells could initiate an synergistic antitumor effect. Methods: The retroviral vectors pLmB7SN and pLhIL 6SN were transfected into the packaging cell line CRIP and the virus particles containing IL 6 or B7 gene were used to infect EL 4 tumor cells, obtaining the cell lines EL 4 IL 6, EL 4 B7 and EL 4 IL 6+B7. B6 mice were injected subcutaneously with various EL 4 transfectant cells and tumor growth conditions were observed. The vaccine potency of the above engineered EL 4 variants was analyzed. Results: When mice were immunized with the above irradiated EL 4 transfectant cells and challenged 7 days later with parental EL 4 cells, the survival time of mice was significantly prolonged. However, there is no difference between the survival time of mice vaccination with EL 4 cells transfected with double IL 6+B7 genes and single IL 6 or B7 gene. Conclusion: No synergistic antitumor immunity was observed in double IL 6+B7 genes transfected EL 4 cells.