【摘要】 为探讨血管内皮细胞Ｅ选择蛋白的表达及野生型ｐ５３ 基因对其表达的影响， 采用流式细胞术及ＲＴＰＣＲ法分别测定其Ｅ选择蛋白及其ｍ ＲＮＡ水平。结果表明： 静息状态的内皮细胞表面检测不到Ｅ选择蛋白的表达， 尽管此时细胞内存在Ｅ选择蛋白的ｍＲＮＡ。肿瘤坏死因子α（ＴＮＦα） 可浓度依赖性地诱导内皮细胞表达Ｅ选择蛋白， 内皮细胞表面Ｅ选择蛋白表达的增加伴随着细胞内Ｅ选择蛋白ｍＲＮＡ 水平的升高。ＴＮＦα刺激内皮细胞后４ ～６ ｈ ，Ｅ选择蛋白的表达达高峰。将ｐ５３ 基因导入内皮细胞后， 经ＴＮＦα诱导的内皮细胞表面Ｅ选择蛋白的表达显著下降， 同时细胞内的Ｅ选择蛋白ｍＲＮＡ 的水平也明显降低。导入ｐ５３ 基因不影响静息状态内皮细胞Ｅ选择蛋白的表达及其ｍ ＲＮＡ 的水平。提示： ｐ５３ 基因至少部分通过降低Ｅ选择蛋白的ｍＲＮＡ 水平而抑制ＴＮＦα诱导的内皮细胞表面Ｅ选择蛋白的表达。更多还原

【Abstract】 To investigate expression of E selectin in endothelial cells (EC) and effect of wild type p 53 gene transduction on its expression, flow cytometry and RT PCR were employed to measure the E selectin protein and mRNA, respectively. The effects of TNFα stimulation and p 53 gene transduction on the expression of E selectin was studied. Flow cytometric analysis revealed that there was no E selectin expression on the surface of resting EC, although its mRNA was detectable by RT PCR. TNFα(10—1 000 ku/L)induced E selectin expression on the surface of EC in a concentration dependent manner. The level of E selectin mRNA was also increased with the increasing concentrations of TNFα. The expression of E selectin protein was notable after 2 h of TNFα stimulation and reached a peak at 4—6 h, then rapidly declined to around the basic level by 12 h. Transduction of p 53 gene inhibited TNFα induced EC expression of E selectin. The E selectin positive cell proportion was reduced from(21.31±1.06)% to(11.83±0.98)%, ( n = 3, P < 0.001). The E selectin mRNA level was also reduced correspondingly. In resting EC, neither E selectin nor its mRNA level was affected by the transduction of p 53 gene. The results indicated that p 53 gene inhibited TNFα induced expression of E selectin on the surface of EC, at least partially, by reducing its mRNA level.更多还原