重组人肿瘤坏死因子对人结肠癌SW－480细胞在体外的杀伤作用研究

文中报道了重组人肿瘤坏死因子（ｒｈＴＮＦ）对人结肠癌细胞株ＳＷ－４８０的克隆抑制和细胞毒作用。改良噻唑兰（ＭＴＴ）法表明ＴＮＦ在６００００ｕ／ｍｌ时才有明显的细胞毒作用说明ＳＷ－４８０对ＴＮＦ低度敏感，而且无剂量依赖关系．但克隆抑制试验表明１０ｕ／ｍｌ就可明显抑制ＳＷ－４８０集落的生长，并有剂量依赖性，且在剂量１５０ｕ／ｍｌ以上时抑制作用随时间而增强．３Ｈ－ＴｄＲ掺入测定的ＴＮＦ抑制ＳＷ－４８０细胞ＤＮＡ合成和ＭＴＴ法测定的细胞毒曲线一致说明ＴＮＦ对ＳＷ－４８０的主要作用是抑制ＤＮＡ合成．ＴＮＦ对ＳＷ－４８０抑制后超微结构变化：最初是胞膜出现微孔，然后细胞内线粒体变性，溶解，核固缩，溶解，最后细胞溶解．这些结果与ＭＴＴ法细胞毒试验及３Ｈ－ＴｄＲ掺入试验相结合说明ＴＮＦ对ＳＷ－４８０杀伤作用主要针对细胞核内外染色体的ＤＮＡ合成上．

Studies of the effects of recombinant human tumor necrosis factor on human colon carcinoma cell line SW-480 in vitro

The cytotoxic and colony inhibiting effects of recombinant human tumor necrosis factor(rhTNF)on human colon carcinoma cell line SW-480 were observed in vitro with modified MTT and 3H-TdR incorporation. It was found that rhTNF 60 000 u/ml exerted obvious cytotoxic effect on SW-480 cells and the effect was not dosage-dependent.The SW-480 cells seemed to be low sensitive to rhTNF.However,the colony inhibiting test revealed that rhTNF 10 u/ml was capable of inhibiting the growth of SW-480 cell colonies in a dosage =dependent manner.When the dosage of rhTNF was larger than 150 u/ml,the inhibition was increased with the prolongation of time.The ultrastructural changes of SW-480 cells after rhTNF treatment were small holes on the cell membrane in the initial stage,then degeneration and lysis of the mitochondria,pyknosis,karyolysis and eventually cytolysis.On the basis of the fact that the curve of the cytotoxic effect of rhTNF determined with MTT and that of the colony inhibiting effect determined with 3H-TdR incorporation were consistent,it is believed that the lethal effects of rhTNF on the SW-480 cells were mainly on the inhibition of the DNA synthesis of intra-and extranuclear chromosomes of the cells.