GM-CSF基因转导对人乳腺癌细胞免疫原性及致瘤性的影响

Effects of GM - CSF Gene Transduction on the Immimogenicity and Tumorigenicity of Human Breast Cancer Cells

应用重组GM-CSF逆转录病毒感染人乳腺癌MCF-7细胞,获得稳定分泌GM-CSF的细胞株(MCF-GM)并对其生物学行为进行了观察。结果显示,MCF-GM细胞生长速度减慢;细胞增殖周期中G_0/G_1期DNA含量百分比升高。^(51)Cr-4小时释放实验表明,MCF-GM细胞对LAK细胞杀伤作用的敏感性显著降低。RNA杂交分析发现,MCF-GM细胞c-myc基因mRNA水平显著下降。结果还显示,MCF-GM细胞表面HLA-Ⅰ类抗原表达的阳性细胞百分数升高,而其表面HLA-Ⅱ类抗原表达无明显变化。本研究为GM-CSF应用于瘤苗研究奠定了实验基础。

The GM - CSF gene was transduced into the human breast cancer MCF - 7 celis by retroviral in-fection, and the specific activity of GM - CSF was determined to range from 500 - 800 U per 106 transduced MCF-7 (MCF- GM) celis in 24 hours. The studies of growth kinetics and cell cycle showed that most of MCF - GM cells were in resting stage. Slot blot analysis of the mRNA level of c - myc oncogene expression in MCF - GM cells indicated that reduction of c - myc mRNA level in MCF - GM celis when compared with MCF - 7 cells. Analysis of the expression of cell surface antigen -HLA was performed by flow cytometry, and the percentage of HLA -ABC positive cells was found to be higher in MCF - GM population than that in MCF - 7 celis, while similar expression of HLA - DR molecules was observed in both cases. 4h - Cr release microcytotoxicity assay results showed the sus-ceptibility of MCF - GM cells to LAK cell killing was less than non- transduced cells.