二氢叶酸还原酶基因在肿瘤生物治疗中的作用

THE EFFECT OF DIHYDROFOLATE REDUCTASE GENE ON BIOTHERAPY OF CANCER

目的 :为了保护骨髓免受或少受化疗药物的损伤 ,用转染人类突变二氢叶酸还原酶 (DHFR)基因反转录病毒载体 ,研究其耐药特性及在小鼠造血细胞的表达和对造血细胞的保护作用。方法 :将含有DHFR基因的病毒上清转染小鼠骨髓造血细胞 ,将转染后的骨髓细胞从尾静脉回输给经致死量 (9Gy)照射的小鼠 ,用MTX和G4 18筛选。结果 :经G4 18和MTX筛选均可得到阳性克隆 ,实验组小鼠白细胞计数和红细胞压积逐渐恢复正常 ,而对照组小鼠 30d内全部死亡。结论 :经初步研究表明 ,该反转录病毒载体能成功转染小鼠造血细胞 ,并表达目的基因 ,使在MTX筛选下重建小鼠造血功能。

Objective:To protect the bone marrow cells from chemotherapeutic injuries, using retroviral vector of mutant human dihydrofolate reductase gene, the paper investigated its drug resistant characteristics and for murine hematopoietic cells transduction and protection. Methods:Using the packaging cell line to transfect murine bone marrow cells by coculture. The transfected murine bone marrow cells were returned to lethally irradiated (9Gy) recipients. Meanwhile the MTX and geneticine were given.Results:The positive clones were found in different G 418 concentrations.The murine transplanted with infecting marrow cells containing DHFR gene. showed protection from lethal MTX toxicity.The WBC count and hematocrit of murine for experiment have recovered gradually to the normal, but the murine for control was died within 30 days. Conclusion:The murine bone marrow cells can be transfected successfully using retroviral vector and can express the foreigh gene.