白血病细胞HL-60诱导分化后LMP/TAP的表达变化及其意义

Changes of the LMP/TAP gene expressions and its significance in leukemia cells HL-60 after induced differentiation

目的研究急性髓系白血病细胞HL-60诱导分化后抗原处理相关转运体蛋白(TAP)及低分子量蛋白酶体(LMP)在该细胞模型中的表达变化及其意义。方法本实验分对照组、ATRA诱导组和PMA诱导组;Wright-Gimesa染色观察HL-60细胞形态,流式细胞术检测细胞表面标记CD11b、CD14的表达,RT-PCR检测LMP/TAP在mRNA水平的表达,Western blotting检测细胞TAP2基因的蛋白表达。结果 0.8μmol/L全反式维甲酸(ATRA)和50 nmol/L乙酸肉豆蔻佛波酯(PMA)分别作用HL-60细胞72 h后可显著抑制细胞增殖,并诱导细胞向成熟粒细胞及巨噬细胞方向分化;CD11b和CD14表达水平均明显升高(P均<0.05);TAP/LMP的mRNA表达水平及TAP2的蛋白表达水平均升高(P均<0.05)。结论白血病来源的单核样细胞具有一定的免疫功能表型,为进一步研究LMP/TAP在白血病免疫逃逸中的作用奠定基础。

Objective To investigate the expression and significance of low molecular weight poly-peptide （LMP） and transporter associated with antigen processing （TAP） in leukemia cells HL-60 after induced differentiation. Methods The cells were divided into the control group, ATRA-induced goup and PMA-induced group. Cell morphology was observed by Wright-Giemsa staining. The expressions of cell surface markers CDllb and CD14 were measured by flow cytometry. TAP1, TAP2, LMP2 and LMP7 mRNA were measured by RT-PCR, and TAP2 proteins were determined by Western blotting. Results After treated for 72 hours, 0.8 μmol/L all-trans retinoic acid （ATRA） and 50 nmol/L phorbol myristate acetate （PMA） restrained the HL-60 cell proliferation and induced the cells to differentiate into the mature granulocyte and mononuclear macrophages; the expression levels of CDllb and CD14 significantly increased （ all P 〈 0.05 ） ; there were significant changes in the expressions of TAP1, TAP2, LMP2, and LMF7 mRNA （ all P 〈 0.05） ; the protein expression level of TAP2 was obviously decreased （ P 〈 0.05 ）. Conclusion Leukemia-derived mononuclear cells have certain immune function phenotype, which lay the foundation for further study of LMP/TAP in leukemia immune escape.