Adhesins of Escherichia coli associated with extra-intestinal pathogenicity confer binding to colonic epithelial cells.
Escherichia coli adhesins are virulence factors in intestinal and extra-intestinal infections, but their role in normal intestinal colonization has not been defined. We investigated the intestinal adherence of E. coli with Dr hemagglutinin, S fimbriae, CFA/I or CFA/II, using freshly isolated ileal or colonic enterocytes and cells from the human colonic cell line HT-29. E. coli with S-fimbrial adhesins (Sfa I or Sfa II), P or type 1 fimbriae, adhered in a non-polarized manner, and in similar numbers to colonic and ileal enterocytes. S fimbriae of the variety Sfa II (originating from a meningitis isolate), mediated a stronger binding than Sfa I (of uropathogenic origin). Strains expressing Dr hemagglutinin adhered preferentially to the brush borders, slightly better to colonic than ileal enterocytes. Strains expressing CFA/I or II adhered to colonic and ileal enterocytes, although brush border adherence was predominantly observed with ileal cells. Binding to HT-29 cells paralleled binding to colonic enterocytes for all adhesin specificities except CFA/I. The results suggest that Dr hemagglutinin, P-, type 1- and S-fimbrial adhesins mediate binding to both colonic and ileal enterocytes. These specificities may contribute to the establishment of E. coli in the intestinal microflora, which precedes their spread to extra-intestinal sites.
Adlerberth
I
I
Department of Clinical Immunology, University of Göteborg, Sweden.
Hanson
L A
LA
Svanborg
C
C
Svennerholm
A M
AM
Nordgren
S
S
Wold
A E
AE
D018830:Adhesins, Escherichia coli / Q000378:metabolism*; D001422:Bacterial Adhesion; D001426:Bacterial Proteins / Q000378:metabolism; D002478:Cells, Cultured; D003106:Colon / Q000166:cytology / Q000382:microbiology*; D004847:Epithelial Cells; D004926:Escherichia coli / Q000302:isolation & purification / Q000378:metabolism* / Q000472:pathogenicity; D036781:Fimbriae Proteins; D019073:HT29 Cells; D006388:Hemagglutinins / Q000378:metabolism; D006801:Humans; D007082:Ileum / Q000166:cytology / Q000382:microbiology
D018830:Adhesins, Escherichia coli; D001426:Bacterial Proteins; D006388:Hemagglutinins; C022924:colonization factor antigens; D036781:Fimbriae Proteins