肿瘤抗原冲击的树突状细胞对小鼠肾细胞癌的治疗作用研究

Immunotherapy of mouse renal cell carcinoma with tumor lysate-pulsed dendritic cells

目的树突状细胞(dendritic cell,DC)疫苗是近年来肿瘤免疫治疗的热点,文中观察肿瘤冻融抗原体外冲击的DC对肾细胞癌(renal cell carcinoma,RCC)的治疗作用。方法反复冻融法制备肿瘤抗原,Lowry法测定肿瘤抗原蛋白浓度,小鼠重组巨噬细胞粒细胞集落刺激因子(human granulocyte-macrophage colony stimulating factor,GM-CSF)、白细胞介素-4(Interleukin-4,IL-4)培养扩增小鼠DC,肿瘤抗原体外冲击制备DC瘤苗,DC瘤苗与淋巴细胞混合培养诱导细胞毒性T淋巴细胞(cytotoxic Tlymphocyte,CTL),LDH释放法测定CTL的杀伤活性,小鼠皮下接种Ranca细胞荷瘤后72h皮下接种DC瘤苗,1次/周,共接种3次,荷瘤后4周取瘤体称重。结果小鼠RCC Ranca细胞冻融抗原体外冲击制备的DC瘤苗具有典型的DC形态特征与免疫表型特征,在体外能有效诱导肿瘤特异性CTL生成,对于小鼠RCC Ranca细胞具有较强的杀伤作用,体内接种DC瘤苗治疗组小鼠肿瘤体积较等渗盐水对照组及细胞因子激活的杀伤(lymphokine activated killev,LAK)细胞治疗对照组明显缩小,DC瘤苗治疗组小鼠的瘤体重较等渗盐水对照组(P<0.01)及LAK细胞治疗对照组(P<0.05)显著减小。结论肿瘤冻融抗原体外冲击的DC瘤苗对小鼠RCC具有明显的治疗作用,本研究为DC免疫治疗复发、难治性RCC提供了实验依据。

Objective Dendritic cells（DC）-based tumor vaccines are the hot-point of immunotherapy in recent years.This study is to observe the therapeutic effect on mouse renal cell carcinoma with tumor lysate pulsed DC.Methods Tumor antigens were prepared from repeated freeze-thaw tumor lysate,Lowry method was used to determine protein concentration.Recombinant mouse GM-CSF and IL-4 were used to expand mouse bone marrow derived DC.Pulsed tumor lysate in vitro was used for preparation of DC vaccine.DC vaccines were cultured with lymphocytes to induce cytolytic T lymphocyte（CTL） in vitro.LDH release methods were used to determine anti-tumor activity of the CTL.Mice were inoculated subcutaneously with Ranca cells,and after 72h,DC vaccines were inoculated subcutaneously once a week for 3 times.Four weeks later the tumors were seized and weighed.Results The mouse renal cell carcinoma lysate pulsed DC had the typical morphological features and immunophenotypic characteristics of mature DC.DC vaccine could effectively induce Ranca-specific CTL in vitro.The tumor volume of mice injected with DC vaccine was significantly reduced compared with NS control group and LAK cell therapy group.The tumor weight of DC vaccine treated mice decreased significantly compared with NS control group（P0.01） and LAK cell therapy group（P0.05）.Conclusion The tumor lysate pulsed DC vaccine has obvious therapeutic effect for mouse renal cell carcinoma.This study provides an experimental basis for DC vaccine immunotherapy of renal cell carcinoma.