Adhesion patterns of commensal and pathogenic Escherichia coli from humans and wild animals on human and porcine epithelial cell lines

Abstract

BackgroundDifferent strategies of colonization or infection by E. coli result in formation of certain adhesion patterns which help also in classifying intestinal E. coli into pathotypes. Little is known about adhesion patterns and host- and tissue adaption of commensal E. coli and about E. coli originating in clinically healthy hosts carrying pathotype-specific virulence-associated genes.FindingsAdhesion pattern of E. coli (n = 282) from humans and from 18 animal species were verified on intestinal human Caco-2 and porcine IPEC-J2 cells and, furthermore, for comparison on human urinary bladder 5637, porcine kidney PK-15 epithelial and HEp-2 cells. The analysis was carried out on 150,000 images of adhesion assays.Adhesion patterns were very diverse; 88 isolates were completely non-adherent, whereas 194 adhered to at least one cell line with the dominant adhesion patterns “diffusely distributed” and “microcolony formation”. Adhesion patterns “chains” and “clumps” were also visible. Chain formation was mediated by the presence of epithelial cells. Clump formation was very specific on only the 5637 cell line. All enteropathogenic (eae+) E. coli (EPEC; n = 14) were able to form microcolonies which was cell line specific for each isolate. Most EPEC formed microcolonies on intestinal IPEC-J2 and Caco-2 but several also on urinary tract cells. Shigatoxin-producing (stx+) E. coli (n = 10) showed no specific adhesion patterns.ConclusionsE. coli isolates were highly diverse. Commensal and pathogenic isolates can adhere in various forms, including diffuse distribution, microcolonies, chains and clumps. Microcolony formation seems to be a global adhesion strategy also for commensal E. coli.

Arcobacter butzleri isolates exhibit pathogenic potential in intestinal epithelial cell models

“…However, variances in adhesion properties of several Escherichia coli isolates depending on investigated cell lines has been described recently (Frommel et al . ).…”

“…Whether this is due to the difference in intestinal tissue origin or due to differences between the host species has to be determined in further studies. However, variances in adhesion properties of several Escherichia coli isolates depending on investigated cell lines has been described recently (Frommel et al 2013).…”

Genotypic and Phenotypic Characteristics Associated with Biofilm Formation by Human Clinical Escherichia coli Isolates of Different Pathotypes

“…VideoScan fluorescence imaging technology. The VideoScan technology implemented in the Aklides system (GA Generic Assays GmbH, Dahlewitz, Germany) is a versatile platform for the analysis of fluorescent objects (30,31,(83)(84)(85). The inverse motorized fluorescence microscope consists of commercial hardware components and in-house-developed software.…”

“…The VideoScan technology, which is based on fully automated fluorescence microscopy, enables the analysis of multiplex assays such as microbead, droplets, and cell-based assays or assays in solution (30)(31)(32)(33). We expanded this VideoScan technology during this study for high-throughput screening of biofilms.…”

Molecular Detection of Diffusely Adherent Escherichia coli Strains Associated with Diarrhea in Shiraz, Iran

“…E. coli DNA was extracted using the DNA extraction kit (QIAGEN Ltd., Crawley, UK), according to manufacturer's instructions. The specific set of primers used to detect daaD in a single reaction is shown in Table 1 (14,15).…”