大肠杆菌K1株对人脑微血管内皮细胞的侵袭及侵袭基因功能分析

Invasion analysis of E.coli K1 to HBMEC andfunction anlysis of invasion genes

关键词:  大肠杆菌：ibeB  HBMEC  基因转染

Key words:  E.coli K1  HBMEC  transfection  ibeB

摘要:

［目的］ 研究大肠杆菌侵袭相关基因在侵袭过程中的作用和相互关系 ［方法］ 将大肠杆菌侵袭基因缺失突变株俩两混合侵袭人脑微血管内皮细胞（HBMEC）并计算各混合组的相对侵袭率。应用基因转染技术将脑内皮细胞侵袭基因B（ibeB）基因导入HBMEC获得稳定转染的细胞克隆，再利用化学荧光免疫荧光技术检测ibeB基因转染的HBMEC细胞骨架与细胞间紧密连接的变化。［结果］ 各混合组的相对侵袭率显著不同分别为100%、76%、44%，前两组数据之间（P=0.36）无显著差异，前两组与后一组数据之间（P<0.01）且两组细菌的组合对HBMEC的侵袭具有明显的协同作用；ibeB基因转染的HBMEC细胞骨架与细胞间紧密连接都发生了变化。 ［结论］ ibeB基因转染HBMEC的确可以使HBMEC形态改变，说明ibeB基因的产物是细胞骨架和紧密连接的调节蛋白。

Abstract:

［Objective］ To study the functiuon invasion genes of E.coli and relationship of each invasion gene. ［Methods］ Invasion assay:mix each of two mutant bacteria with different invasion gene mutation,incubate with HBMEC monolayer for some time ,determine the numbers of bacteria invaded.Transfection and cytoskeleton and tight junction assay of HBMEC:Transfect HBMEC with plasmid carrying ibeB to obtain a constantly transfected HMEC; The transfected HBMEC were tested for cytoskeleton and tight junction change by fluorescence method. ［Results］The mixed bacteria of different group shew different invasion rate 100%，76%，44%， and the first two groups of mixed bacteria（P=0.36） shew coorperativity in invasion process contrast to the last group（P<0.01）; The cytoskeleton and tight junction of transfected HBMEC changed greatly. ［Conclusion］ The gene product of ibeB play an important role in the regulation of cytoskeleton and tight junction of HBMEC