目的:探讨MHC-Ⅰ类链相关分子A(MHC class I chain-related molecule A,MICA)多态性与乳腺癌细胞对NK细胞杀伤敏感性的关系。方法:测序分析乳腺癌细胞系MCF-7、MDA-MB-231、MDA-MB-435S和SK-BR-3的MICA等位基因,用Western blotting和流...目的:探讨MHC-Ⅰ类链相关分子A(MHC class I chain-related molecule A,MICA)多态性与乳腺癌细胞对NK细胞杀伤敏感性的关系。方法:测序分析乳腺癌细胞系MCF-7、MDA-MB-231、MDA-MB-435S和SK-BR-3的MICA等位基因,用Western blotting和流式细胞术检测MICA重组表达载体转染293T细胞(分别命名为p MCFA5.1、p MCFA4、p231A5R、p231A9和p435A5P)MICA蛋白的表达水平,用LDH法检测NK细胞对转染MICA的293T细胞的杀伤活性,酶联免疫斑点法检测NK细胞穿孔素、颗粒酶B分泌水平。结果:MCF-7细胞表达MICA*008/A5.1和MICA*001/A4,MDA-MB-231和SK-BR-3细胞均表达MICA*019/A5和MICA*002/A9,MDA-MB-435S细胞表达MICA*010/A5。转染MICA后,p MCFA5.1组293T细胞MICA蛋白的表达水平最低(P<0.05),p435A5P组次之(P<0.05),p MCFA4组、p231A5R组和p231A9组表达水平较高(均P<0.05)。NK细胞对转染MICA的293T细胞杀伤活性及穿孔素、颗粒酶B分泌:p435A5P组对NK细胞杀伤的敏感性最低(P<0.05),穿孔素、颗粒酶B分泌水平最低(均P<0.05);p MCFA5.1、p MCFA4、p231A5R和p231A9各组之间比较差异无统计学意义(P>0.05)。结论:MICA基因多态性与乳腺癌细胞对NK细胞杀伤的敏感性密切相关。展开更多
Using human umbilical vein endothelial cells (HUVEC) and porcine aortic endothelial cells (PAEC) as target cells, human peripheral blood NK cells (PBNK) and NK92 cells as effector cells, the differential cytotoxicitie...Using human umbilical vein endothelial cells (HUVEC) and porcine aortic endothelial cells (PAEC) as target cells, human peripheral blood NK cells (PBNK) and NK92 cells as effector cells, the differential cytotoxicities of NK cells to allo- and xeno-endothelial cells were studied. The influence of MHC class I molecules on the cytotoxicity of human NK cells was assayed using acid treatment, and blockades of MHC class I antigens, CD94 and KIR (NKB1). The results indicated that the killing of PAEC by the two kinds of NK cells is higher than that of HUVEC. After acid-treatment, the cytotoxicity of the two kinds of NK cells to PAEC and HUVEC is significantly enhanced, but the magnitude of the enhancement is different. The enhancement of NK killing to acid treated HUVEC is much greater than that to PAEC. Blockade of CD94 mAb did not alter the NK cytotoxicity, while blockade of NKB1 mAb enhanced the cytotoxicity of PBNK to HUVEC and PAEC by 95% and 29% respectively. The results above suggested that the differential recognition of MHC I molecules of xeno-endothelial cells by human NK cells could be the major reason for higher NK cytotoxicity to PAEC. KIR might be the primary molecule that transduced inhibitory signals when endothelial cells were injured by NK cells.展开更多
文摘Using human umbilical vein endothelial cells (HUVEC) and porcine aortic endothelial cells (PAEC) as target cells, human peripheral blood NK cells (PBNK) and NK92 cells as effector cells, the differential cytotoxicities of NK cells to allo- and xeno-endothelial cells were studied. The influence of MHC class I molecules on the cytotoxicity of human NK cells was assayed using acid treatment, and blockades of MHC class I antigens, CD94 and KIR (NKB1). The results indicated that the killing of PAEC by the two kinds of NK cells is higher than that of HUVEC. After acid-treatment, the cytotoxicity of the two kinds of NK cells to PAEC and HUVEC is significantly enhanced, but the magnitude of the enhancement is different. The enhancement of NK killing to acid treated HUVEC is much greater than that to PAEC. Blockade of CD94 mAb did not alter the NK cytotoxicity, while blockade of NKB1 mAb enhanced the cytotoxicity of PBNK to HUVEC and PAEC by 95% and 29% respectively. The results above suggested that the differential recognition of MHC I molecules of xeno-endothelial cells by human NK cells could be the major reason for higher NK cytotoxicity to PAEC. KIR might be the primary molecule that transduced inhibitory signals when endothelial cells were injured by NK cells.
