Real-time PCR quantification of bacterial adhesion to Caco-2 cells: competition between bifidobacteria and enteropathogens

Res Microbiol. 2005 Sep;156(8):887-95. doi: 10.1016/j.resmic.2005.04.006. Epub 2005 Jun 9.


Probiotic bacteria play an important role in protecting the host from intestinal colonization of pathogenic bacteria. We have developed a new analytical approach based on a real-time PCR technique for quantifying Bifidobacterium adhesion to intestinal epithelial cells. Real-time PCR analysis showed that adhesion to enterocyte-like Caco-2 cells represented a variable phenotype in the genus Bifidobacterium, enabling classification of three adhesion behaviors: high adhesiveness (>40 bifidobacterial cells/Caco-2 cell); adhesiveness (5-40 bifidobacterial cells/Caco-2 cell); no adhesiveness (<5 bifidobacterial cells/Caco-2 cell). This molecular methodology was successfully used in competition studies in enteropathogens. All bifidobacterial strains examined evidenced displacement activity towards important enteropathogens (S. typhimurium, Y. enterocolitica and E. coli EPEC). Real-time PCR is a rapid, accurate and sensitive method for detecting and quantifying different bacterial genera and species simultaneously adhering to a epithelial cell monolayer.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Bacterial Adhesion / physiology*
  • Bifidobacterium / genetics
  • Bifidobacterium / physiology*
  • Binding, Competitive
  • Caco-2 Cells / microbiology*
  • Cell Line
  • Enterobacteriaceae / genetics
  • Enterobacteriaceae / physiology*
  • Epithelial Cells
  • Humans
  • Polymerase Chain Reaction / methods
  • Species Specificity