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

[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另q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。

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

[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