抗CD44抗体HI44a诱导THP-1细胞凋亡作用的研究

Apoptosis of Human Leukemia THP-1 Cells Induced by Anti-CD44 Antibody

背景与目的:研究抗CD44抗体HI44a体外诱导白血病细胞THP-1凋亡的作用及其机制。材料与方法:应用Annexin-Ⅴ/PI染色法、原位凋亡检测试剂盒及透射电镜分别检测形态学变化及其凋亡情况,RT-PCR及western-blot方法检测原癌基因c-mycmRNA及蛋白水平的表达,JC-1染色法检测细胞线粒体膜电位的变化,流式细胞仪检测抗凋亡蛋白Bcl-2的表达。结果:采用多种方法均可证实,HI44a对THP-1细胞有明显的诱导凋亡作用。HI44a明显抑制THP-1细胞抗凋亡蛋白Bcl-2的表达(P<0.05);同时c-myc在mRNA及蛋白水平的表达水平均明显降低;并可诱导细胞线粒体膜电位的改变。结论:HI44a能够有效诱导THP-1细胞凋亡。其作用机制可能与调节相关癌基因及抗凋亡蛋白的表达,降低线粒体膜电位有关。

BACKGROUND ＆ AIM： The present study was designed to determine the apoptosis-inducing effects of H144a, an anti-CD44 monoclonal antibody, on THP-1 leukemia cells and to investigate its mechanism of action.MATERIAL AND METGODS： The effect of H144a on leukemia cells apoptosis was assayed by annexin-V/PI staining,ultrastructural changes and in situ cell death detection assay. RT-PCR and Western-blot were used to examine the expression of c-myc at both mRNA and protein levels. The expression of Bcl-2 and mitochondrial potential were examined using FACS. RESULTS： All tests showed that H144a effectively induced apoptosis of THP-1 cells. When treated with H144a, the level of c-myc expression in leukemic cells obviously decreased at both mRNA and protein levels, and the intracellular level of Bcl-2 protein also decreased. Moreover, H144a could effectively induce changes in mitochondrial membrane potential of the THP-1 cells. CONCLUSION： H144a effectively induced apoptosis of THP-1 cells. These activities of the anti-CD44 antibody may be associated with its inhibitory effect on oncogene and anti-apoptosis protein expressions,and changes in mitochondrial membrane potential.