Distinctive patterns of adherence of enteropathogenic Escherichia coli to HeLa cells.

We showed that Escherichia coli strains attach to HeLa cells in two different patterns. In one, the bacteria cover the whole surface of the cell (diffuse adherence), and in the other, attachment is limited to one or a few sites of the cell surface (localized adherence). Among the enteropathogenic strains, serogroups O55, O86, O11ab, O119, O125, O128ab, and O142 usually showed localized adherence when tested in the presence of D-mannose. Localized adherence was not shown either by E. coli strains isolated from urine or by enteroinvasive and enterotoxigenic E. coli strains. Some of these strains showed diffuse adherence. Some strains of serogroups O55, O111, and O119 showed both localized and diffuse adherence in the same preparation. Mannose-resistant adherence was not related to colonization factor antigens.