肺癌细胞中NKG2D配体MICA及ULBP高表达及其在CIK介导的肿瘤细胞杀伤中的作用

High expression level of NKG2D ligands MICA and ULBP in lung cancer cell and the role in CIK mediated cytotoxicity

目的:探索肺癌细胞中NKG2D配体的表达量及其与CIK细胞介导的肿瘤细胞毒性的关系。方法:在肺癌组织、癌旁组织及肺癌细胞株中用实时荧光定量PCR及蛋白质免疫印迹法检测NKG2D配体的表达量。应用流式细胞仪检测肿瘤细胞株A549和QG56表面NKG2D配体的表达情况。体外分离培养CIK细胞,比较NKG2D单克隆抗体预处理CIK细胞和无NKG2D单克隆抗体预处理CIK细胞介导的肿瘤细胞毒性。结果:NKG2D在肺癌组织及肺癌细胞株中高表达。CIK细胞对肺癌细胞株A549表现出较强的细胞毒性,但用NKG2D单克隆抗体预处理CIK细胞后可显著降低这种作用(P<0.05)。结论:NKG2D配体在肺癌组织和肺癌细胞株中高表达。对于CIK细胞介导的肺癌细胞杀伤作用,NKG2D与其配体的相互作用至关重要。

Objective： To identify the expression level of NKG2 D ligands in lung cancer cell and the interaction between NKG2 D and NKG2 D ligands in the CIK mediated cytotoxicity against tumor cells. Methods： We used RTPCR and Western-blot to detect the expression level of NKG2 D ligands in lung cancer tissue,para-carcinoma tissues and cell lines. The expression of NKG2 D ligands in the surface of lung cancer cell lines was determined by flowcytometry. CIK cells were isolated and cultured in vitro. The anti-NKG2 D mA bs treated CIK and non-anti-NKG2 D mA bs treated CIK cells mediating cytotoxicity against A549 was determined by flow cytometry also. Results：NKG2D ligands highly expressed in lung cancer cells. The CIK cells caused cytolysis against the A549,but this cytolysis was decreased（ 30% ± 3. 2%） by pretreatment of CIK cells with anti-NKG2 D mA bs. Conclusion： The present study demonstrates the higher expression level of NKG2 D ligands in lung cancer tissue than para-carcinoma tissue. The killing effect of lung cancer cells by CIK cell is partially mediated by NKG2D-NKG2 D ligand interaction. The interaction between NKG2 D and NKG2 D ligands play a vital role in the CIK mediated tumor cell killing.