PapG-dependent adherence breaks mucosal inertia and triggers the innate host response

J Infect Dis. 2004 May 1;189(9):1734-42. doi: 10.1086/383278. Epub 2004 Apr 14.


Mucosal pathogens differ from normal flora constituents in that they provoke a host response that upsets mucosal integrity. We investigated whether the elaboration of discrete adherence factors is sufficient to break the inertia of the mucosal barrier. PapG-mediated adherence was selected as an example, because P fimbrial expression characterizes uropathogenic Escherichia coli and because adherence starts the attack on the mucosal barrier. Patients were inoculated intravesically with transformed nonvirulent E. coli strains expressing functional P fimbriae (E. coli pap(+)) or mutant fimbriae lacking the adhesin (E. coli Delta papG). E. coli pap(+) was shown to activate the innate host response, and adherent gfp(+) bacteria were observed on excreted uroepithelial cells. E. coli Delta papG failed to trigger a response and was nonadhesive. We conclude that PapG-mediated adherence breaks mucosal inertia in the human urinary tract by triggering innate immunity and propose that this activation step differentiates asymptomatic carriage from infection.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adhesins, Escherichia coli / genetics
  • Adhesins, Escherichia coli / immunology*
  • Adhesins, Escherichia coli / metabolism*
  • Adult
  • Aged
  • Bacterial Adhesion*
  • Colony Count, Microbial
  • Escherichia coli / genetics
  • Escherichia coli / immunology
  • Escherichia coli / metabolism
  • Escherichia coli Infections / immunology
  • Escherichia coli Infections / microbiology
  • Escherichia coli Proteins / metabolism
  • Female
  • Fimbriae Proteins / genetics
  • Fimbriae Proteins / immunology*
  • Fimbriae Proteins / metabolism*
  • Fimbriae, Bacterial / metabolism
  • Humans
  • Immunity, Innate*
  • Male
  • Middle Aged
  • Mucous Membrane / immunology*
  • Urinary Tract / microbiology
  • Urinary Tract Infections / immunology
  • Urinary Tract Infections / microbiology


  • Adhesins, Escherichia coli
  • Escherichia coli Proteins
  • PapG protein, E coli
  • Fimbriae Proteins