摘要
目的:探讨自然杀伤(NK)细胞与表达NKG2D配体的人鼻咽癌细胞株CNE2混合培养24h时CNE2细胞表面HLAI类分子及MHCI类链相关分子(MICA/MICB)的变化及编辑前、后的CNE2细胞对NK细胞杀伤敏感性的差异.方法:PCR-SSP法检测NK细胞KIR分型,流式细胞仪检测编辑前的CNE2细胞(单纯培养的CNE2细胞),编辑后的CNE2细胞(NK细胞与CNE2细胞10∶1混合培养24h)表面HLAI类分子及MHCI类链相关分子(MICA/MICB)的表达情况,LDH释放法测定3例健康者的NK细胞在不同效靶比时对编辑前、后的CNE2细胞的杀伤活性.结果:编辑前、后的CNE2细胞表面MICA/MICB的表达率分别为(88.67±2.81)%和(34.53±3.15)%,两者相比差异有统计学意义(P<0.01);编辑前、后的CNE2细胞表面HLAI类分子表达率分别为(99.77±0.12)%和(97.80±0.87)%,两者相比差异无统计学意义(P>0.05).NK细胞对编辑前、后的CNE2细胞的杀伤活性在效靶比10∶1时分别为(26.96±1.47)%和(6.60±0.86)%,两者相比差异有统计学意义(P<0.01);效靶比20∶1时分别为(35.74±3.59)%和(11.57±2.02)%,两者相比差异有统计学意义(P<0.01).结论:CNE2细胞与NK细胞持续性接触24h,CNE2细胞表面HLAI类分子表达无改变,MI-CA/MICB表达下调,导致编辑后的CNE2细胞激发NK细胞杀伤活性下降.本研究初步证明了NK细胞对编辑后的肿瘤细胞杀伤活性下降的分子基础,同时为我们如何提高NK细胞的杀伤活性提供了新的干预的靶点.
AIM： To analyze the changes of HLA class Ⅰmolecules, MHC class Ⅰ chain-related molecules （MICA/MICB） on human nasopharyngeal carcinoma cell line （ CNE2 ） after 24 h coculture with NK cells and NK cell-mediated cytolysis. METHODS： The expressions of HLA class Ⅰ molecules and MICA/MICB on the surface of CNE2 cells and edited CNE2 cells （ coculture of NK cells with CNE2 cells for 24 h at E/T ratios of 10：1） were analyzed by flow cytometry. The KIR genotypes （isolated from 3 healthy persons） were determined by PCR-SSP, and cytotoxicities of NK cells were detected by LDH releasing assay. RESULTS ： After 24 h culture, the expression of MICA/MICB on the CNE2 cells and the edited CNE2 cells were （88. 67 ± 2.81）%, （34.53 ±3.15）%, respectively （P〈0.01） ; the expression of HLA class I molecules on CNE2 cells and the edited CNE2 cells were （ 99. 77 ± 0. 12 ） %, （ 97. 80 ± 0. 87 ） %, respectively, and there was no difference in HLA class I molecule expression between them （ P 〉 0.05 ）. The cytotoxicity against CNE2 and edited CNE2 cells mediated by NK cells were （26.96±1.47）%, （6.60±0.86）% at E：Tratios of 10：1, （35.74±3.59）%, （11.57 ±2.02）% at E：T ratios of 20：1,respectively. NK cells displayed lower cytotoxicity against the edited CNE2 cells than that against the CNE2 cells （ P 〈 0.01 ）. CONCLUSION： Downregulating MICA/MICB expression on NK cells-edited tumor cells leads to low capacity to trigger NK cellmediated cytolysis. Our research highlights the molecular mechanism of reduced cytotoxicity mediated by NK cells and the potential molecular target for boosting NK cell-mediated cytolysis against the edited tumor cells.
出处
《第四军医大学学报》
北大核心
2007年第11期1005-1007,共3页
Journal of the Fourth Military Medical University
基金
国家自然科学基金(30471636)
关键词
鼻咽肿瘤
杀伤细胞
天然
HLA
I类分子
MHC
I类链相关分子
免疫编辑
nasopharyngeal neoplasms
killer cell, natural
HLA class Ⅰ molecules
MHC class Ⅰ chain related molecules （MICA/MICB）
immunoediting
