苦参碱对K562细胞NKG2D配体表达的影响及其机制研究  

Up-regulation of NKG2D ligand ULBP2 by matrine in K562 cells and the underlying molecular mechanisms

作　　者：马玲娣[1] 朱志超[1] 卢绪章[1] 蒋丽佳[1] 周民[1] 钱思轩[2] 李建勇[2] 

机构地区：[1]南京医科大学附属常州市第二人民医院,常州213000 [2]南京医科大学第一附属医院、江苏省人民医院血液科

出　　处：《中华血液学杂志》2014年第5期438-442,共5页Chinese Journal of Hematology

基　　金：国家自然科学基金（81101647）

摘　　要：目的 探讨苦参碱对白血病细胞表面NK细胞活化性受体凝集素样同型二聚体（NKG2D）配体表达的影响及可能的分子机制.方法 用流式细胞术检测苦参碱处理前后慢性髓性白血病细胞系K562细胞表面NKG2D四种配体分子MICA/B、ULBP1、2、3表达的改变,观察不同浓度苦参碱作用后K562细胞对人NK细胞杀伤的敏感性.Western blot分析苦参碱处理前后K562细胞信号转导与转录活化因子3（STAT3）表达的改变.结果 与未处理组相比,苦参碱处理可显著诱导K562细胞表面ULBP1和ULBP2分子的表达,尤以ULBP2增高最为显著.0.8 mg/ml苦参碱处理后,K562细胞ULBP1和ULBP2表达平均荧光强度（MFI）由处理前的220和615分别增加至429和1 614,MICA/B和ULBP3表达则无明显改变.苦参碱（浓度分别为0.2、0.5和0.8 mg/ml）处理可增强NK细胞对K562细胞的杀伤作用.效靶比5：1时,NK细胞对K562细胞杀伤百分率由处理前的29.2％分别增加至32.8％、38.1％和40.5％.苦参碱对K562细胞STAT3总蛋白表达没有明显影响,但可显著抑制磷酸化STAT3水平.结论 苦参碱可诱导K562细胞NKG2D的配体表达上调,增强K562细胞对NK细胞杀伤敏感性,其分子机制与细胞内STAT3的活性抑制相关.Objective To probe matrine acting on natural killer cell （NK） activating receptor NKG2D ligands expression in CML cell line K562 and its underlying molecular mechanism. Methods The expression of NKG2D ligands （major histocompatibility complex class I chain-related molecule A or B （MICA/B）, UL16-binding proteins （ULBP） 1, 2, and 3 on K562 cells were analyzed before and after treated with matrine by FCM. The cytotoxic sensitivity of K562 to NK cell was detected by FCM after CFSE staining at different effect-to-target （E/T） cell ratios. The expression of signal transduction and transcriptional activator 3 （STAT3） protein as well as phosphorylated STAT3 （p-STAT3） were detected by western blot. Results After treatment with matrine, ULBP1 and ULBP2 expression, especially ULBP2 on K562 cells significantly increased, with mean fluorescence intensity （MFI） increasing to 615 and 1 614 by 220 and 615 in the untreated cells, respectively. There was no significant change for MICA or ULBP3 expression. Matrine enhanced the susceptibility of K562 cells to NK-mediated cell lysis. At the ratio of E/T with 5：1, the proportion of the killed K562 cells increased to 32.8%, 38.1% and 40.5%, respectively （after 0.2, 0.5 and 0.8 mg/ml matrine treatment） by 29.2% in the untreated cells. The phosphorylated STAT3 protein, but not STAT3 protein, was significantly inhibited by matrine treatment in K562 cells. Conclusion Matrine induced the expression of NKG2D ligands in K562 cells and enhanced the cytotoxicity of NK ceils against K562, which was closely related to the inhibition of STAT3 activity in K562 cell.

关 键 词：苦参碱 K562细胞 NKG2D配体 STAT3转录因子 杀伤细胞 天然 

分 类 号：R285[医药卫生—中药学]