姜黄素提高白血病KG1a细胞对同种异体NK细胞杀伤的敏感性及其分子机制探讨  

Effects of ALLO-NK cell cytotoxicity against leukemic cell lines KG1a treated with Curcumine and their molecular mechanism

作　　者：陈伟[1] 刘玉莹[1] 杜苑苑[1] 王玲[1] 

机构地区：[1]广东省第二人民医院血液科,510317

出　　处：《新医学》2011年第10期655-660,共6页Journal of New Medicine

基　　金：2010年建设中医药强省立项资助课题(2010242)

摘　　要：目的:研究姜黄素作用前后白血病KG1a细胞对同种异体自然杀伤(NK)细胞杀伤的敏感性变化,并初步探讨其分子机制。方法:以对同种异体NK细胞杀伤高度敏感的白血病K562细胞为对照,乳酸脱氢酶释放法检测KG1a细胞对同种异体NK细胞杀伤的敏感性,流式细胞仪检测细胞表面NKG2D配体(MICA/B、ULBP1、ULBP2、ULBP3)和HLA-Ⅰ类分子蛋白表达,逆转录PCR法检测细胞表面NKG2D配体和HLA-Ⅰ基因mRNA的表达水平。CCK-8法检测姜黄素对KG1a细胞半数抑制量(IC50),以此含量作用KG1a细胞,再次乳酸脱氢酶释放法检测姜黄素作用后的KG1a对同种异体NK细胞杀伤的敏感性,流式细胞仪检测姜黄素作用后的KG1a细胞表面NKG2D配体和HLA-Ⅰ类分子蛋白表达水平。结果:与K562细胞比较,KG1a细胞对同种异体NK细胞杀伤呈低度敏感,KG1a细胞表面NKG2D各配体蛋白表达阳性率均明显低于K562细胞(P<0.01),HLA-Ⅰ蛋白表达阳性率则明显高于K562细胞(P<0.01);在mRNA水平两种白血病细胞表面均有NKG2D配体和HLA-Ⅰ基因表达。当效靶比为5∶1、10∶1、20∶1时,姜黄素作用后NK细胞对KG1a细胞杀伤率明显高于作用前(P<0.01);作用后KG1a细胞各NKG2D配体表达率均明显升高(P<0.05或0.01),HLA-Ⅰ类分子无明显变化(P>0.05)。结论:姜黄素能提高KG1a细胞对同种异体NK细胞杀伤的敏感性,其机制可能与姜黄素提高KG1a细胞表面NKG2D配体的表达有关。Objective： To study the effects of ALLO-NK cell cytotoxicity against leukemic cell lines KG1a treated with Curcumine and to preliminarily explore their molecular mechanisms.Methods： Taking ALLO-NK highly sensitive K562 cells as controls,cytotoxicity of NK cells isolated from 5 healthy volunteers against two leukemia cells was analyzed by LDH releasing assay at different effector-to-target cell ratios（E∶ T）.The expressions of NKG2D ligands and HLA-classⅠmolecule were assayed by flow cytometery;the mRNA expression of NKG2D ligands in two kind of cells was measured by RT-PCR;CCK-8 test was conducted to find out the 50 % inhibition concentration of Curcumine and this level of Curcumine was chosen to treat KG1a cells;cytotoxicity of ALLO-NK cells was analyzed by LDH releasing assay and the expressions of NKG2D ligands and HLA-classⅠmolecule were assayed by flow cytometery after treating with Curcumine once again.Results： KG1a cells is not sensitive to ALLO-NK cells.The expressions of NKG2D ligands were positively detected in the two cells at mRNA level,but they were significantly higher in K562 cells than KG1a cells at the protein level（P0.05）.However,the expression of NKG2D ligands in KG1a cells was up-regulated（P0.05）and no significant difference of expression of HLA-classⅠmolecules was observed after treateing with Curcumine（P0.05）.Conclusion： Curcumine could obviously up-regulate NKG2D ligands expression in KG1a cells and thus enhance the cytotoxicity of NK cells against KG1a cells.

关 键 词：姜黄素 白血病KG1a细胞 白血病K562细胞 自然杀伤细胞 NKG2D配体 细胞毒性实验 

分 类 号：R285[医药卫生—中药学]