Texosomes在肺癌高剂量放疗远隔效应中的作用和机制研究

The immune regulation mechanism of abscopal effect induced by high-dose radiotherapy (HDRT) remains unclear. Our previous research shows that tumor cells treated with a high-dose radiation highly express programmed cell death ligand-1 (PD-L1) and release exosomes (Texosomes), which function as the "double switch" of the immune suppression. Removal of these two immune suppressions under PD-L1 blockade (anti-PD-L1) may be a precondition for abscopal effect, and miR-495-3p could play an important role in immune regulation. This project aims to obtain abscopal effects in animal models of subcutaneous xenograft and lung metastasis under HDRT plus anti-PD-L1, and then to explore the molecular components of Texosomes, investigate its influence on immune cells and its regulation by miR-495-3p. We also intend to rescue the abscopal effects by transfusing Texosomes back to animal models, and verify the effects of miR-495-3p and Texosomes on immune function and abscopal effects, and finally to test the immune effects clinically. This research may reveal the important effects and molecular mechanism of Texosomes in abscopal effects induced by high-dose radiotherapy, thus promoting the treatment of lung cancer

肺癌高剂量放疗诱导远隔效应的免疫调控机制不明。我们发现，高剂量放疗诱导肿瘤细胞高表达PD-L1，并释放Texosomes，组成免疫抑制“双开关”；PD-L1单抗可去除“双开关”免疫抑制，可能是远隔效应的前提条件，miR-495-3p等则是其中关键的免疫调控分子。本项目拟建立肺癌移植瘤及肺转移动物模型，高剂量放疗联合PD-L1单抗诱导远隔效应；获取高剂量放疗及联合PD-L1单抗预处理的移植瘤细胞，检测Texosomes分子组分、对免疫细胞影响及受miR-495-3p调控情况；远隔效应动物模型中，Texosomes回复实验，验证miR-495-3p对免疫功能和远隔效应的调控；在高剂量放疗联合PD-L1单抗的临床标本中，验证miR-495-3p及Texosomes的免疫调控作用。研究结果有望探明Texosomes在肺癌高剂量放疗远隔效应中的作用及分子机制，具有重要的理论意义和应用前景。

肺癌高剂量放疗诱导远隔效应的免疫调控机制不明。本项目拟建立肺癌移植瘤及肺转移动物模型，高剂量放疗联合PD-L1单抗诱导远隔效应；获取高剂量放疗及联合PD-L1单抗预处理的移植瘤细胞，检测Texosomes分子组分、对免疫细胞影响及受miR-495-3p调控情况；远隔效应动物模型中，Texosomes回复实验，验证miR-495-3p对免疫功能和远隔效应的调控；在高剂量放疗联合PD-L1单抗的临床标本中，验证miR-495-3p及Texosomes的免疫调控作用。本研究成功建立了高剂量放疗联合免疫治疗远隔效应的动物模型；同时分离、纯化、鉴定高剂量放疗后肺癌细胞培养上清中exosome；验证了高剂量放疗后肿瘤细胞来源的exosome对免疫细胞的活化和功能有显著的抑制作用；成功构建了外泌体功能敲除细胞株；采用蛋白质谱分析了高剂量放疗对外泌体蛋白谱的影响；最后双荧光素酶检测实验验证miR-495-3p和PD-L1的相互作用。本研究结果可为Texosomes在肺癌高剂量放疗远隔效应中的作用及分子机制做出初步探讨