重组EGFR-γFc融合DNA疫苗联合热疗抗肿瘤免疫的实验研究  

Experimental study of antitumor effect of hyperthermia combined with the recombinant EGFR-γFc infusion DNA vaccine

作　　者：武建毅[1] 刘岽[2] 唐亮[2] 谈立松[2] 黄晓冬[1] 

机构地区：[1]上海市普陀区人民医院肿瘤科,上海200060 [2]同济大学附属肺科医院肺癌免疫研究室,上海200433

出　　处：《同济大学学报（医学版）》2009年第6期34-39,共6页Journal of Tongji University(Medical Science)

基　　金：上海市普陀区卫生局资助项目(PTW08-Z01)

摘　　要：目的构建EGFR-γFc融合DNA疫苗并观察其联合41℃热疗对小鼠移植肿瘤的抑制作用。方法以异种同源鸡EGFR膜外部分与IgG的γFc段的基因片段为基础构建真核表达质粒PVAX1/cEGFR-γFc,免疫荧光法检测融合蛋白在真核细胞中的表达,随后将Lew is肺癌移植瘤小鼠随机分为疫苗组、热疗组、合并组和对照组。疫苗组于每只小鼠双侧股四头肌注射100μg重组质粒,每5 d重复1次,共3次;热疗组对荷瘤小鼠行局部41℃热疗,每5 d重复1次,共3次;联合组小鼠按疫苗组小鼠的同样方法注射质粒后同时行局部热疗;对照组小鼠注射生理盐水。末次处理5 d后ELISA法检测小鼠脾淋巴细胞上清液中细胞因子IL-2和IFN-γ的水平,流式细胞仪测定脾细胞淋巴细胞亚群;观察小鼠荷瘤后的生存率;末次处理后14 d部分成瘤动物处死,取出瘤体称重,计算抑瘤率。结果联合组小鼠脾淋巴细胞TH1型细胞因子IL-2和IFN-γ浓度较其他各组明显升高(P<0.01),CD8+T淋巴细胞数目增加(P<0.01),接瘤后14 d联合组平均瘤重低于其他各组(P<0.01),抑瘤率达70%,接瘤后30 d联合组动物生存率也高于其他各组。结论41℃热疗可能通过细胞免疫增强EGFR靶向DNA疫苗的抗肿瘤效果,热疗联合EGFR靶向DNA疫苗可能是一种有希望的抗肿瘤途径。Objective To evaluate the efficacy of hyperthermia at 41℃ combined with the recombinant EGFR-γFc infusion DNA vaccine on xenografts in mice. Methods Extracellular domain of xenogeneic chicken epidermal growth factor receptor fused with rabbit IgG Fc was successfully inserted into PVAX1 eukaryotic expression vector to construct the recombinant PVAX1/ cEGFR-γFc DNA vaccine. Expression of the fusion protein in eukaryotic cell was detected by immuno-fluorescent assay. The C57BL mice inoculated Lewis lung cancer cells were randomized into the vaccine, hyperthennia, combination and control groups. Each animal in the vaccine group was injected intramuscularly 100 Ixg recombinant plasmid once every 5 days for total 3 times：animals in the hyperthermia group were treated with localized heating at 41 ℃ once every 5 days for total 3 times; animals in the combination group were injected plasmids by the same way as those in the vaccine group and were treated with hyperthermia simultaneously; while the animals in the control group were injected NS only. The levels of cytokines IL-2 and IFN-γ subsets of spleen lymphocyte, cancer inhibition ratio and the survival rate were examined. Results In the combination group, the animal＇ s levels of cytokines IL-2, IFN-γ and CD8^＋ subgroups of spleen T lymphocyte increased significantly than those counterparts in other groups （ P 〈 0.01 ）, the tumor weight was significantly lower （ P 〈 0.01 ）, cancer inhibition ratio was 70%, survival rate and cancer inhibition ratio were significantly higher than those in other groups. Conclusion Hyperthermia combined with recombinant EGFR-γFc infusion DNA vaccine is a potentially promising therapy against tumors.

关 键 词：热疗 肿瘤 DNA疫苗 表皮生长因子受体 IgGγFc 

分 类 号：R392.11[医药卫生—免疫学]