肿瘤坏死因子对培养的人脐静脉内皮细胞骨架的影响

EFFECT OF TUMOR NECROSIS FACTOR ON CYTOSKELETON OF CULTURED HUMAN UMBILIC VEIN ENDOTHELIAL CELLS

目的 :用肿瘤坏死因子 (TNF -α)处理培养的人脐静脉内皮细胞研究不同作用浓度和不同作用时间的TNF-α的刺激对内皮细胞的形态和骨架的影响。结果 :2 0 0 0U的TNF -α处理内皮细胞 8小时 ,细胞形态发生改变 ,细胞间的紧密接触变的松散 ,间隙增宽 ,骨架失去原有的网状形态 ,呈块状收缩。 2 4小时后骨架结构开始恢复 ,细胞形态似成纤维细胞。 1 0 0 0U的TNF -α对内皮细胞影响比较明显 ,8小时后细胞变圆 ,细胞间的接触消失 ,骨架浓缩 ,网状结构消失 ,2 4小时后出现特征性“鸟喙”样改变 ,72小时后不完全恢复。不同浓度的TNF -α刺激内皮不同时间 ,均可使内皮细胞内游离钙比对照组明显增加。结论 :TNF -α可改变内皮细胞的形态结构 ,影响其屏障机能 ,并可能与胞内游离钙浓度相关。

To explore the effect of tumor necrosis factor alpha(TNF-α) on the cytoskeleton.Methods:Conforcal microscope was used to detect the changes of cytoskeleton,intracellular Ca 2+ concentration was determined by Fura2/AM fluorescent loading.Results:Firstly,we found that change of the cytoskeleton of HUVECs induced by TNF-α was different with various concentration and stimulated period.TNF-α 1000 U caused cytoskeleton irreversible change which had concentrated and typical change of 'bird mouth-like'.Meanwhile,cells shape became rounded;cell-cell tight contact become loosed;intercellular space became widen.Secondly,it was observed that the stress fiber disappeared when cells were treated with TNF-α 2000 U for 8 h.Cytoskeleton recovered partially at 24 h,and completely at 72 h.But the morphology of the treated cells were like fibroblasts.Thirdly,with various concentration,TNF-α increased in the concentration of intracellular calcium of HUVECs during different treatment periods.Conclusion:These observations suggest that TNF-α alters the morphology of HUVECs and reduces their defense function.The mechanism of changes induced by TNF-α is partially related to the increase of intracellular calcium concentration of HUVECs.