Wells C L, Jechorek R P, Olmsted S B, Erlandsen S L
Department of Laboratory Medicine & Pathology, University of Minnesota, Minneapolis 55455, USA.
Shock. 1994 Jun;1(6):443-51.
Previous in vivo evidence has shown that bacterial phagocytosis by enterocytes may be an initial step in bacterial translocation across the intestinal epithelium. This study analyzed the interactions of cultured enterocytes, namely Caco-2 cells, with nine strains of enteric bacteria, tested in pure culture and in mixed culture. These nine strains had a spectrum of invasive potential and included Salmonella typhimurium, Listeria monocytogenes (three strains), Escherichia coli (three strains), Proteus mirabilis, and Enterococcus faecalis. Numbers of viable intracellular bacteria recovered from Caco-2 cells were: L. monocytogenes > S. typhimurium > P. mirabilis > E. coli > E. faecalis. Uptake of a given microbe by enterocytes was strain-specific and was not influenced by the presence of another strain, regardless of the invasive ability of the coinfecting strain. Electron microscopic visualization of bacterial adherence and uptake by Caco-2 cells indicated that the epithelial interactions of normal enteric bacteria were similar to these observed with invasive strains of salmonella and listeria.
先前的体内证据表明，肠上皮细胞对细菌的吞噬作用可能是细菌穿过肠上皮进行移位的起始步骤。本研究分析了培养的肠上皮细胞（即Caco-2细胞）与9株肠道细菌在纯培养和混合培养条件下的相互作用。这9株细菌具有一系列不同的侵袭潜力，包括鼠伤寒沙门氏菌、单核细胞增生李斯特菌（3株）、大肠杆菌（3株）、奇异变形杆菌和粪肠球菌。从Caco-2细胞中回收的存活胞内细菌数量依次为：单核细胞增生李斯特菌>鼠伤寒沙门氏菌>奇异变形杆菌>大肠杆菌>粪肠球菌。肠上皮细胞对特定微生物的摄取具有菌株特异性，且不受其他菌株存在的影响，无论共感染菌株的侵袭能力如何。通过电子显微镜观察Caco-2细胞对细菌的黏附和摄取情况表明，正常肠道细菌与上皮细胞的相互作用类似于沙门氏菌和李斯特菌侵袭菌株所观察到的情况。
