两型TNFα杀伤U937细胞的差异表达基因

Differentially Expressed Genes in U937 C ells Induced by the Cytotoxicity of Two Forms of TNFα

目的 比较两型TNFα对U93 7细胞的胞毒效应及二者诱导U93 7细胞差异表达的基因。方法 采用生物活性检测法测定两型TNFα对U93 7细胞的胞毒效应 ;用抑制消减杂交法探索两型TNFα诱导U93 7细胞差异表达基因。结果 两型TNFα对U93 7细胞胞毒效应存在差异 ,分泌型TNFα (sTNFα)的杀伤率为 2 4 3 % ,且引起靶细胞坏死率大于其诱导的凋亡率 ;跨膜型TNFα (TM TNFα)的杀伤率为 3 4 3 % ,主要引起靶细胞凋亡。以sTNFα诱导基因做消减 ,得到TM TNFα诱导的差异表达基因 ,即 2 5个EST ,其中 8个EST与已知基因有高度同源性 ,17个EST为未知序列 ,已向GenBank登录。

Objective To compare the cytotoxicity of two forms of tumor necrosis factor-α (TNF α) a nd study the differentially expressed genes induced by both forms of TNFα in U9 37 cells. Methods The cytotoxic effect of TNFα against U937 cells was determined by bioassay. Sup pression subtractive hybridization(SSH) was used for differentially expressed genes induced by two forms of TNFα in U937 cells. Results There were differences between the cytotoxic effects against U937 cells induced by the two forms of TNFα. The death rate of U937 induced by sTNFα was 24 3 % and the necrotic cells were much more than the apoptotic cells induced by sTNFα . The death rate of U937 mediated by TM-TNFα was 34 3 % and TM-TNFα resulte d mainly in apoptosis. The genes activated by sTNFα served as drivers, by SSH, the differentially expressed genes (25 ESTs) by TM-TNFα were obtained. Among t hem 8 ESTs had high homology with cDNAs in Genbank and the remaining 17 ESTs wer e unknown, which were accepted by Genbank. Conclusion The difference of cytotoxic effect by two forms of TNFα may be due to stimulati on of different gene transcription and activation of different signal molecules.