NK细胞与K562细胞之间相互免疫编辑作用及其对NK细胞杀伤活性的影响  

Reciprocal immunoediting between NK cells and K562 cells and its effect on NK cell-mediated cytotoxicity

作　　者：郭坤元[1,2] 梅家转[1] 姜振宇[3] 姚开泰[4] 

机构地区：[1]南方医科大学珠江医院血液科 [2]南方医科大学基础医学院病理学教研室,广东广州510515 [3]吉林大学第一医院血液肿瘤科 [4]南方医科大学基础医学院病理学教研室

出　　处：《吉林大学学报（医学版）》2007年第4期630-633,共4页Journal of Jilin University：Medicine Edition

基　　金：国家自然科学基金资助课题(30471636)

摘　　要：目的:探讨NK细胞与K562细胞混合培养前、后其杀伤活性的变化及分子机制。方法:流式细胞仪检测NK细胞与K562细胞混合培养前、后细胞表面相应分子的变化,LDH释放法测定效靶比20∶1时NK细胞对K562细胞的杀伤活性。结果:相互编辑前,K562细胞表面MICA/MICB的表达率为(79.90±0.87)%,NK细胞表面NKG2D、KIR2DL1和KIR3DL1的表达率分别为(98.27±0.67)%、(45.70±1.22)%和(35.60±1.35)%。相互编辑后,K562细胞表面MICA/MICB和NK细胞表面NKG2D的表达率分别为(35.56±1.01)和(34.67±3.88)%,均明显低于编辑前(P=0.000);NK细胞表面KIR2DL1和KIR3DL1的表达率分别为(47.20±1.08)%和(34.03±1.20)%,与编辑前比较差异均无显著性(P>0.05)。效靶比20∶1时,NK细胞对编辑后的K562细胞的杀伤活性为(24.07±0.58)%,编辑后的NK细胞对K562细胞的杀伤活性为(16.95±2.00)%,均明显低于编辑前NK细胞对K562细胞的杀伤活性[(54.03±3.46)%](P=0.000)。结论:NK细胞与K562细胞持续性接触后,双方发生了相互免疫编辑作用;NK细胞的杀伤活性下降,其分子机制是细胞表面相应的配受体发生了变化。Objective To analyze the changes of cytotoxicity mediated by NK cells after 24 h coculture with K562 cells and the molecular mechanism. Methods The expressions of MICA/MICB on K562 cells, KIR2DL1, KIR3DL1, NKG2D on NK cells were analyzed by flow cytometry. Cytotoxicity was detected by LDH releasing assay. Results Before editing, the expression rate of MICA/MICB on K562 ceils was （79.90±0.87）%, the expression rates of NKG2D, KIRZDL1, and KIR3DL1 onNK cells were （98.27±0.67）%, （45.70±1.22）% and （35.60±1.35）%, respectively. After editing, the expression rates of MICA/MICB on K562 cells and NKG2D on NK cells were （35.56±1.01）% and （34.67±3.88）%, respectively： compared with before editing, there was significant difference （P=0.000）. The expression rates of KIR2DL1 and KIR3DL1 on NK cells were （47.20±1.08） % and （34. 03±1.20）%, compared with before editing, there was no signficant difference （P〉0.05）. The cytotoxicities against K562 cells by edited NK cells and against the edited K562 cells by NK cells were （24.07±0.58）% and （16. 95±2. 00）% at an effector-to-target （E/T） ratio of 20 ： 1, both were lower than the cytotoxicity against K562 cells by NK cells （54.03%±3.46%）, the differences were significant （P = 0.000）. Conclusion Reciprocal immunoediting between NK cells and K562 cells induced by 24 h cocuhure leads to decreased cytotoxicity of NK cells. The potential molecular mechanism is the changes of NKG2D and MICA/MICB expressions.

关 键 词：K562细胞 杀伤细胞 天然 NKG2D MHCI类链相关分子 免疫编辑 

分 类 号：R392.12[医药卫生—免疫学]