大肠杆菌侵入肠道肌纤维母细胞

Escherichia coli invaded myofibroblasts

将携带绿色荧光蛋白基因的质粒转化E.coli K12中,体外分离培养肠肌纤维母细胞,将E.coli K12与肠肌纤维母细胞体外共培养,观察大肠杆菌是否侵入肌纤维母细胞并在细胞内存活。结果表明:在感染后2 h,大肠杆菌可粘附并侵入肌纤维母细胞,有大量成簇状和散状的大肠杆菌侵入细胞,感染后24 h细胞内仍有少量细菌存活。2h感染率和24 h感染率分别为20.3%和3.25%。本试验首次证实大肠杆菌透过细胞膜进入肌纤维母细胞细胞质,为研究肠道肌纤维母细胞在免疫防御中的作用奠定了一定的基础。

pEGFP was transformed into E.coli K12 and mouse intestinal myofibroblasts were cultured in vitro.The myofibroblasts were inoculated with EGFP-K12 for one hour.The invasion and survival of E.coli K12 within myofibroblasts were analyzed by fluorescence microscope at 2 hours and 24 hours of postinfection（P.I.）.After 1 hour infection and 1 hour gentamicin killing extrocelullar bacteria,EGFP-E.coli K12 were seen within the myofibroblasts at 20.3%of infected cells.The bacteria were scattered or clustered within these cells.At 24 hour P.I.,there were only 3.25% of myofiberblasts containing survival EGFP-E.coli K12 were observed.The results firstly proved that EGFP-K12 invaded. and survived within myofibroblasts.It suggests the myofibroblasts may involve in mucosal immune defence.