IFN-γ和TNF-α对甲状腺细胞凋亡的诱导作用

Effect of IFN-γ and TNF-α on apoptosis of thyrocytes

目的探讨IFN-γ和TNF-α对培养的甲状腺细胞凋亡的影响。方法取G raves病(GD)患者甲状腺组织,采用原代细胞培养技术、细胞增殖实验和流式细胞术检测IFN-γ和TNF-α对甲状腺细胞增殖活力、细胞凋亡率以及对Fas蛋白表达率的影响,用ELISA检测IFN-γ和TNF-α刺激甲状腺细胞后培养物上清液中sFas含量的变化。结果与对照组相比,单独IFN-γ组、TNF-α组和IFN-γ/TNF-α联合组甲状腺细胞凋亡率、Fas蛋白表达率以及培养上清液中sFas含量均明显增加(P<0.01),甲状腺细胞增殖活力均明显降低(P<0.01),且IFN-γ/TNF-α联合组效应最强(P<0.01)。单独IFN-γ组、TNF-α组和联合组诱导的细胞凋亡率与Fas蛋白表达率的相关性有统计学意义(P<0.01)。结论IFN-γ和TNF-α能诱导甲状腺细胞凋亡,且这种诱导作用具有协同效应。

Objective To investigate the effect of interferon-γ（IFN-γ） and tumor necrosis factor-α（TNF-α） on the apoptosis of thyrocytes cultured in vitro.Methods Thyrocytes from GD patients were cultured in the absence or presence of IFN-γ and TNF-α.The cell proliferation was determined by MTT method.Cell apoptosis and Fas expression on thyrocytes were tested by flow cytometry.The concentration of soluble Fas（sFas） in the cultured supernatant was measured by ELISA Kit.Results Compared with that of the untreated cells,the proliferation of thyrocytes was significantly decreased in 100 U/ml IFN-γ,TNF-α,or IFN-γ/TNF-α treated groups（P0.01）.A significant higher ratio of apoptotic cells and higher levels of Fas/sFas expression were also observed in the three treated groups（P0.01）,and the combination of IFN-γ with TNF-α had synergistic effect on the proliferation of thyrocytes,ratio of apoptotic cells,and levels of Fas/sFas expression（P0.01）.There was a positive correlation between the ratio of apoptotic cells and the level of Fas expression on thyrocytes（P0.01）.Conclusions IFN-γ and TNF-α may induce the apoptosis of thyrocytes by the increased expression of Fas,and they have synergistic effect on the induction of the apoptosis of thyrocytes.