【作者】 周亚娟； 臧爱华； 夏泠； 杨春旭； 何忠时； 周勇； 张慧； 韩光； 谢丛华；

【机构】 武汉大学第二临床学院； 湖北省肿瘤医院； 武汉大学中南医院放化疗科；

【摘要】 目的:研究γ射线与IFN-γ协同作用于小鼠巨噬细胞系RAW264.7的效应机制,以及γ射线IFN-γ协同作用后小鼠巨噬细胞对细胞间粘附分子-1(ICAM-1)及巨噬细胞相关抗原-1(MAC-1)的表达及意义,从而探讨γ射线对巨噬细胞激活途径的影响,并推测放射性损伤中巨噬细胞的作用机制。方法:克隆形成实验测定不同剂量γ射线照射RAW264.7后的细胞存活分数;流式细胞仪测定细胞凋亡率;Griess反应测定细胞NO表达;实时定量QT-PCR测定细胞ICAM-1、MAC-1 mRNA表达;蛋白免疫印迹方法测定细胞裂解液中ICAM-1,MAC-1蛋白表达。结果:小鼠巨噬细胞系RAW264.7细胞与对照组相比2Gy、4GY、6Gy及8Gy细胞存活分数分别为87.17%,52.83%,15.11%及1.47%,而剂量从1Gy增加至20Gy细胞凋亡率从10.3%升高到18.7%;5Gyγ射线与IFN-γ协同作用于RAW264.7可显著增强细胞上清中NO的生成、以及ICAM-1及MAC-1表达,而且这些效应均比γ射线或IFN-γ单因素的作用要强。结论:提高射线剂量可显著降低小鼠巨噬细胞系RAW264.7细胞存活分数及增加其细胞凋亡率,射线与IFN-γ协同作用可显著增强巨噬细胞NO生成,并提高巨噬细胞表面粘附分子及其配体表达,可能是放射性肺炎中巨噬细胞的作用机制之一。更多还原

【Abstract】 AIM:To explore the effect of activating the murine macrophage cell line RAW 264.7 by bothγ-rays and IFN-γand to study the expression of intercellular cell adhesion molecule-1 and its ligand induced by y-rays and IFN-γ.METHODS:Plate clone formation assays were performed to measure survival fraction of RAW 264.7 cells received various dose ofγ-rays.Flow cytometry was used to detect the cell apoptosis rates. Griess reactions were applied to determine the NO product in supernatant of exposed cells.The mRNA expression of ICAM-1 and MAC-1 was recorded by Real-time quantitative RT-PCR method.The protein expression of ICAM-1 and MAC-1 was detected by Western blot withβ-actin as control.RESULTS: Colony assay showed the survival fraction to be 87.17%,52.83%,15.11% and 1.47%compared with control group after irradiation at 2,4,6 and 8 Gy.Meanwhile,the cell apoptosis rates increase from 10.3%to 18.7%with the increase of dosage from 1GY to 20GY.The rise of the level of NO、ICAM-1 and MAC-1 was observed in the condition of 5GYγ-rays coaction with 200u/ml IFN-γ.The effect of using bothγ-rays and IFN-γwas stronger than that of singleγ-rays or IFN-γtreatment.CONCLUSION:γ-rays could notably decrease the survival fraction and enhance the apoptosis rates of RAW 264.7 cells in a dose-depend way.The expression of N0、intercellular cell adhesion molecule-1 and its ligand on the murine macrophage cell line RAW264.7 were significantly enhanced under combined action ofγ-rays and IFN-γ,which may be one of the roles the macrophages play in radiation pneumonitis.更多还原