The Effect of Postnatal Age on the Adherence of Enterohemorrhagic Escherichia coli to Rabbit Intestinal Cells

Abstract

ABSTRACT. Enterohemorrhagic Escherichia coli (EHEC) are associated with hemorrhagic colitis and hemolytic uremic syndrome. These illnesses are typically seen in young children, but are rare before 6 mo of age.The cause of this age restriction is unclear. Because bacterial adherence to intestinal mucosa is considered a critical initial event in pathogenesis, we studied the ontogeny of the adherence of EHEC (0157:H7 and other serotypes) isolated from children with diarrhea, hemorrhagic colitis, or hemolytic uremic syndrome. Adherence was quantitatively determined by incubating radiolabeled bacteria with viable rabbit intestinal cells, which were prepared by treating loops of distal ileum and proximal colon with EDTA, D m , and citrate. Cells obtained from animals of different ages were studied simultaneously. The adherence of the various EHEC strains varied significantly. A non-0157:H7 E. coli strain 43-12 bound best (35 and 32 bacterialcell to ileal and colonic cells, respectively) with 4 8 4 0 % inhibition by mmannose and a-methyl mannoside ( p < 0.01) and 20-28% inhibition by L-fucose ( p c 0.05), but no significant inhibition by other carbohydrates. Analysis of variance and polynomial regression showed that postnatal age significantly affected the adherence to ileal and colonic cells. Adherence during the 1st wk of life was 13-19% of that in the adult animal; it increased gradually, reaching the adult level at about 4 wk of age. Our study shows that postnatal age affects the adherence of EHEC to intestinal cells. These findings are compatible with postnatal development of gut receptors and may be relevant to the age-related risk of EHEC disease in children. (Pediatr Res 29: 14-19, 1991) Abbreviations EHEC, enterohemorrhagic Escherichia coli HUS, hemolytic uremic syndrome SLT, Shiga-like toxin Cytotoxin-producing Escherichia coli have been recently recognized as a cause of nonbloody diarrhea and hemorrhagic colitis

Intestinal adherence associated with type IV pili of enterohemorrhagic Escherichia coli O157:H7

“…E. coli O157:H7 strains bind in vitro to several cultured cell types (14)(15)(16) and in vivo to the gastrointestinal tracts of chickens, gnotobiotic piglets, newborn rabbits, and neonatal calves (14,(17)(18)(19). In adult cattle, the terminal recto-anal junction is thought to be the primary site of colonization of the bovine gastrointestinal tract (20).…”

The adherence of verocytotoxin-producing Escherichia coli to rabbit intestinal cells

“…The aim of this study was to examine the adherence of a number of serotypically distinct VTEC strains from different geographic locations by a quantitative, radiolabelled assay that has been described previo~sly.~~? 24 Adherence was also confirmed morphologically by scanning electronmicroscopy. Plasmid profiles of the bacteria, hybridisation with the 3.4-kbDNA probe and the presence of surface fimbriae were determined.…”

“…Scanning electronmicroscopy was performed essentially as described previously, 24 to visualise the adherence of bacteria to intestinal mucosa. Intestinal sections, placed on Dot blot apparatus to get defined exposed surfaces, were incubated with bacteria (0.2 ml; 6 x lo9 bacteria/ml for 45 min).…”

Pathology of Pediatric Gastrointestinal and Liver Disease

“…E.coli O157:H7 is among the three most common bacterial enteropathogens (trailing Salmonella and Campylobacter) and is the most frequently isolated pathogen from stool of patients with frank hematochezia (Griffi n et al 1990 ;Pai et al 1984 ). Individuals at extremes of age appear most susceptible, with children younger than 4 years at greatest risk for infections and susceptibility to hemolytic-uremic syndrome (Ashkenazi et al 1991 ;Cimolai et al 1990 ;Spika et al 1986 ). Hemolytic-uremic syndrome (HUS) occurs in about 12 % of children with E.coli O157:H7 infection (Ostroff et al 1989 ).…”