瘤体内直接注射白细胞介素-7基因抗小鼠乳腺肿瘤免疫效应的研究

目的 观察瘤体内直接注射白细胞介素(IL)-7基因抗小鼠乳腺肿瘤免疫效应.方法 构建IL-7真核表达质粒(pcDNA3-IL-7)；建立乳腺癌TM40D细胞BALB/C小鼠移植模型；瘤体内直接注射pcDNA3-IL-7,观察小鼠肿瘤体积变化；酶联免疫吸附试验(ELISA)法检测外周血干扰素(IFN)-γ含量；流式细胞仪检测胞内IFN-γ的分泌量；局部肿瘤经治疗后行常规病理分析.结果 成功构建pcDNA3-IL-7；与对照磷酸盐缓冲液(PBS)组(115.2±11.8) ng/L、pcDNA3组(133.6±9.4) ng/L比较,pcDNA3 -IL-7注射组(242.3±10.1)ng/L外周血IFN-γ明显增高；pcDNA3-IL-7明显抑制肿瘤生长(P＜0.05)；流式细胞仪检测显示pcDNA3-IL-7显著促进CD4+T细胞、CD8+T细胞内IFN-γ的分泌量；常规病理显示pcDNA3 -IL-7注射组肿瘤组织大量坏死,炎性细胞和大量淋巴细胞浸润.结论 瘤体内直接注射pcDNA3-IL-7明显抑制小鼠乳腺肿瘤生长,显著促进IFN-γ分泌,增强了小鼠机体抗乳腺肿瘤的免疫效应.

Antitumor immune effect of interleulin-7 gene for mouse mammary cancer treated with direct iatratumoral injection

Objective To observe the antitumor immune effect of interleukin (IL)-7 gene for mouse mammary cancer treated with direct intratumoral injection.Methods IL-7 was constructed into the eukaryotic expression plasmid ( pcDNA3-IL-7 ) ; breast cancer cell TM40D BALB/C mice transplantation model was established ; direct intratumoral injection of IL-7 eukaryotic expression plasmid DNA was done;changes of tumor volume in mice were monitored; Enzyme linked immunosorbent assay (ELISA) assays were used to examine peripheral blood interferon (IFN)-γproduction in tumor-bearing mice; the expression levels of intracellular IFN-γ in tumor-bearing mice spleen cells were detected by using flow cytometry;local tumor after treatment underwent routine pathological analysis.Results IL-7 was successfully constructed into the eukaryotic expression plasmid ( pcDNA3-IL-7 ) ; the tumor growth rate in pcDNA3-IL-7 injection group was significantly reduced as compared with control group (P ＜ 0.05 ) ; the production of peripheral blood IFN-γ in pcDNA3-IL-7 injection group (242.3 ± 10.1 ) ng/L was significantly higher than in PBS group ( 115.2 ± 11.8) ng/L and pcDNA3 group ( 133.6 ± 9.4) ng/L; the secretion of intracellular IFN-γ in CD4 + T cells and CD8 + T cells was increased significantly; routine pathologic examination showed that there were significant histological changes ( a large number of visible tumor necrosis,plentiful inflammatory cells and large lymphocytes infiltration) in the mice with direct intratumoral injection of IL-7.Condusion Direct intratumoral injection of IL-7 gene eukaryotic expression plasmid significantly can inhibit the growth of mammary tumors in mice,significantly promote IFN-γ secretion in mice,and enhance the body' s immune response to mouse mammary tumor.