Nataro J P, Scaletsky I C, Kaper J B, Levine M M, Trabulsi L R
Infect Immun. 1985 May;48(2):378-83. doi: 10.1128/iai.48.2.378-383.1985.
Histopathological evidence suggests that the adherence of enteropathogenic Escherichia coli (EPEC) to the mucosa of the small bowel is an important step in pathogenesis. Several reports have shown that many EPEC isolates adhere to HEp-2 and HeLa cells in tissue cultures. In the HeLa cell assay, there are at least two distinct patterns of adherence: localized adherence, which is characterized by the formation of bacterial microcolonies, and diffuse adherence, in which bacteria cover the cell uniformly. We have found that these two patterns can be demonstrated in HEp-2 cells as well as in HeLa cells and that the results of the two assays are closely correlated. Using a DNA probe which is sensitive and specific for localized adherence to HEp-2 cells, we provide evidence that localized adherence and diffuse adherence by EPEC are due to at least two genetically distinct adhesions which confer phenotypic differences in both the morphology of HEp-2 cell adherence and in surface hydrophobicity. The two factors are each encoded on plasmids which vary in size from 55 to 70 megadaltons; one strain exhibiting localized adherence carried these genes on the chromosome.
组织病理学证据表明，肠致病性大肠杆菌（EPEC）对小肠黏膜的黏附是发病机制中的重要一步。多项报告显示，许多EPEC分离株在组织培养中能黏附于HEp-2和HeLa细胞。在HeLa细胞检测中，至少有两种不同的黏附模式：局部黏附，其特征是形成细菌微菌落；弥漫性黏附，即细菌均匀覆盖细胞。我们发现这两种模式在HEp-2细胞和HeLa细胞中均可表现出来，且两种检测结果密切相关。使用对HEp-2细胞局部黏附敏感且特异的DNA探针，我们提供了证据表明，EPEC的局部黏附和弥漫性黏附至少归因于两种基因上不同的黏附素，它们在HEp-2细胞黏附形态和表面疏水性方面赋予了表型差异。这两个因子分别由大小从55至70兆道尔顿不等的质粒编码；一株表现出局部黏附的菌株将这些基因携带在染色体上。
