小剂量放疗介导人肾透明细胞癌786-0免疫原性表达的变化

Expressions of immunogenic molecules in low-dose radiotherapy-treated human renal clear cell carcinoma 786-O cells

目的探讨小剂量放疗对人肾透明细胞癌786-0细胞免疫原性相关钙网蛋白（CRT）、组织相容性复合物（MHC）-I、MHC—II表达量的影响。方法用CCK-8法检测放疗对786—0细胞的生长抑制作用；4种不同放射剂量（0、6、12、24Gy）作用于786-0细胞，用流式细胞术检测细胞凋亡情况及膜表面的CRT、MHC—I、MHC-Ⅱ分子的表达。结果随着照射剂量的增加（0、6、12、24Gy），放疗对786-0细胞增殖的抑制率加大。各组CRT的表达量与对照组比较差异均有统计学意义（均P〈0．001），以12Gy组作用最强。随着照射剂量的增加，钙网蛋白的平均荧光强度出现先增高后下降的趋势（CRT：0Gy为47．3％±2．8％；6Gy为106．3％±5．8％；12Gy为248．3％±8．5％；C24Gy为125．5％±6．8％）。各实验组MHC-I和MHC-Ⅱ的表达量与对照组相比差异均有统计学（P〈0．05），且随照射剂量增加而增加，并呈剂量依赖关系。结论小剂量放疗能够有效诱导。肾透明细胞癌786-0细胞膜表面免疫原性相关膜分子CRT、MHC—I、MHC-Ⅱ的表达。

Objective To explore the effects of low-close radiation on the expression of immunogenic membrane molecules ealreticulin （CRT） and MHC- I / Ⅱ on the surface of human renal clear ceil carcinoma 786-0 cells. Methods The inhibitory activity of low-dose radiation on cell line 786-0 was examined by CCK-8 assay. And the post-radiation membrane expressions of CRT, MHC- I and MHC- Ⅱ were measured by flow cytometry while CRT was visualized by immunofluoreseence photography. Results The inhibition rates on the proliferative capacities of four 786-0 cell lines rose with the incremental radiation doses of 0, 6, 12 and 24 Gy. And the CRT expression levels of each experimental group was significantly higher than that of the control group （ P 〈 0. 001 ）. Along with incremental doses of irradiation, the average ealretieulin fluorescence intensities increased gradually initially and then there was a downward trend. The membrane expressions of MHC- I and MHC- Ⅱ of each experimental group was significantly higher than those of the control group （P 〈0. 05）. As the irradiation dose increased, the average MHC- i fluorescence intensities increased gradually in a dose-dependent manner. Conclusion The low-dose radiotherapy may up-regulate CRT and MHC class I / Ⅱ related with the immunogenicity of tumor cells to induce immune response against