【摘要】 为了探讨干扰素-γ对胃癌细胞(SGC₇₉₀₁)肿瘤坏死因子（TNF）受体的影响及干扰素—γ肿瘤坏死因子突变体（TNF—m）协同抗肿瘤的机制,以₁₂₅I-肿瘤坏死因子突变体(¹²³I—TNF—m)为配体,用放射配体结合分析法研究了干扰素-γ对SGC₇₉₀₁细胞TNF受体表达及TNF—m内化和降解的影响。外用MTT法研究了干扰素-γ与TNF-m协同抗肿瘤作用。结果表明:干扰素-γ使SGC₇₉₀₁细胞TNF受体数目由0.56×10^-11 nmol/细胞增加到0.94×10^-11nmol/细胞（P<0.01）,而对受体亲和力无影响(kd值:2.78×10^-10mol对2.64×10^-10 mol.P>0.5);干扰素-γ可明显增加TNF—m内化和降解的绝对数量而对其比率无影响。干扰素-γ使TNF—m对SGC₇₉₀₁细胞的最大杀伤率由60.48%上升到96.76%（P<0.01）。提示:干扰素-γ通过上调TNF受体而加强TNF—m的体外抗肿瘤作用。更多还原

【Abstract】 To explore the effect of interferon-γ （IFN-γ） on tumor necrosis factor （TNF） receptor of human gastric cancer cells (SGC₇₉₀₁) and the mechanism of anti-tumor synergism of IFN-γ and tumor necrosis factor mutant （TNF-m）, radio-ligand binding assay was applied to detect the effect of IFN-γ on the expressin of TNF receptor on SGCT₇₉₀₁ cell and on the internalization and degradation of TNF-m. MTT colorimetric method was used in the study of anti-tumor synergism of IFN-γ and TNF-m. Results showed: The number of TNF receptor on SGC₇₉₀₁ cell increased from 0.56×10^-11 nmol/cell to 0.94×10^-11 nmol/cell （P<0.01）, with no effect on the affinity of the receptors. (kd value: 2.78×10^-10mol versus 2.64×10^-10mol, P>0.5). IFN-γ could promote the synthesis of TNF receptor protein; IFN-γ could markedly increase the absolute number of the internzalization and degradation of TNF-m but exerted no effect on their rate. The maximum rate of cytotoxicity of TNF-m on SGC₇₉₀₁ increased from 60.48% to 96.76%（P<0.01） owing to IFN-γ. It was indicated that IFN-γ could increase in vitro the anti-tumor effect of TNF-m by up-regulating TNF receptors.更多还原