bcr-abl和白介素-7共表达基因疫苗诱导小鼠免疫保护作用

Immune protective mechanisms of gene vaccines with co-expressing bcr-abl fusion gene fragment and mouse IL-7 gene

目的探讨小鼠白介素-7（IL-7）基因对bcr-abl融合基因疫苗诱导机体免疫应答的影响。方法采用pVbcr-abl／mIL-7质粒免疫BALB／c小鼠，检测小鼠血清中bcr-abl特异性抗体水平。以转染bcr-abl融合基因片段的SF2／0细胞为靶细胞，用LDH释放实验检测免疫小鼠脾细胞特异性细胞毒活性。结果pVbcr-abl／mIL-7质粒能诱导小鼠产生血清特异性抗bcr-abl抗体，pVbcr-abl／mIL-7免疫组的血清特异性抗体滴度高于pVbcr-abl免疫组，脾细胞杀伤SP2／0／bcr-abl靶细胞的细胞毒活性明显增强。结论共表达bcr-abl和mIL-7的基因疫苗能在小鼠体内诱导较高的特异性体液免疫和细胞免疫水平，为慢性粒细胞白血病基因疫苗的临床前实验研究提供了依据。

Objective To investigate the influence of raiL-7 on the immune response induced by vaccine of bcr-abl fusion gene fragment in mouse. Methods BALB/c mice were immunized by i. m. injection of pVbcr-abl/mIL-7 and pVbcr-abl, respectively. The specific antibody to p210^bcl-abl protein was assayed by ELISA, The CTL activity of spleen cells from the immunized mice was assessed with LDH release test. Results The pVbcr-abl/mIL-7 and pVbcr-abl-immunized BALB/c mice elicited higher specific antibodies to p210^bcr-abl protein. The specific antibody level of former group was higher than that in latter group, but the difference was statistically not significant. The spleen cells from the immunized mice showed more effective CTL activity than that from control group. The cytotoxic activity of spleen CTLs induced by pVbcr-abl/mIL-7 immunized mice exceeded that of pVbcr-ab-immunized mice. Conclusion The mIL-7 may influence the growth and differentiation of T cells, promote some T cells migrating into tumor tissue and up-regulate the specific cellular immune response. The results of this study provided an useful experimental basis for preclinical research on gene vaccine for chronic myeloid leukemia.