Attachment of bacteria to intestinal epithelial cells in diarrhea caused by Escherichia coli strain RDEC-1 in the rabbit: stages and role of capsule

J Infect Dis. 1981 Feb;143(2):219-30. doi: 10.1093/infdis/143.2.219.


RDEC-1 is a strain of Escherichia coli that, in rabbits, attaches to intestinal mucosal epithelial cells bereft of microvillar borders and causes diarrhea by an unknown mechanism. The stages of attachment of RDEC-1 bacteria to mucosal epithelial cells were examined using high-voltage electron microscopy of thick (0.5-micrometers) sections of ileum and cecum of rabbits with diarrhea. The tissues were stained with ruthenium red or antisera to strain RDEC-1 OK antigens. Micrographs, including stereopairs, demonstrated several stages of bacterial attachment. Bacteria were attached to the glycocalyxes of epithelial cell microvilli and to pedestal-like extrusions of the surfaces of epithelial cells lacking microvilli. Structures consistent with bacterial pili were rarely visualized. Attachment to microvilli appeared to be a result of the interaction of polysaccharides of the microvillar glycocalyx and the K antigen of the bacterial capsule.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Animals
  • Attachment Sites, Microbiological*
  • Diarrhea / immunology*
  • Diarrhea / pathology
  • Epitopes
  • Escherichia coli / immunology
  • Escherichia coli / ultrastructure
  • Escherichia coli Infections / immunology*
  • Escherichia coli Infections / pathology
  • Fimbriae, Bacterial
  • Intestinal Mucosa / immunology*
  • Intestinal Mucosa / ultrastructure
  • Lysogeny*
  • Microvilli / immunology
  • Microvilli / ultrastructure
  • Polysaccharides, Bacterial / immunology
  • Rabbits


  • Epitopes
  • Polysaccharides, Bacterial