从小鼠脾细胞提取总ＲＮＡ，通过ＲＴＰＣＲ得到含信号肽的小鼠γ干扰素（ｍＩＦＮγ）全长ｃＤＮＡ，经测序鉴定后将其克隆到含标记基因ＮｅｏＲ的逆转录病毒载体ｐＬＸＳＮ中，采用脂质体法将其导入包装细胞ＰＡ３１７，经过包装，用含ｍＩＦＮγ基因的缺陷型病毒上清感染小鼠肝癌细胞，经Ｇ４１８筛选建立起ｍＩＦＮγ基因修饰株。ＰＣＲ、ＲＴＰＣＲ、Ｓｏｕｔｈｅｒｎ及Ｎｏｒｔｈｅｒｎ杂交结果显示有ｍＩＦＮγ及标记基因的转入和表达。生物学活性测定也表明该基因修饰株细胞培养上清中有一定活性的ＩＦＮγ分泌。 Total RNA was extracted from mouse spleen cells and the full-length cDNA of mouse IFN-γ containing signal peptide was obtained by RT-PCR. After sequencing, it was cloned into the retroviral vector pLXSN containing marker gene NeoR. In the method, liposome was used to introduce PA317 into packaging cells, and after packaging, the mouse hepatoma cells were infected with the supernatant of the deficient virus containing mIFN-γ gene. The mIFNγ gene-modified strain was established by G418 screening. The results of PCR, RT-PCR, Southern and Northern hybridization showed that mIFN-γ and marker genes were transferred and expressed. The biological activity test also showed that there was a certain activity of IFN-γ secretion in the cell culture supernatant of the modified gene.