Flamingo cadherin: a putative host receptor for Streptococcus pneumoniae

J Infect Dis. 2007 Jun 15;195(12):1828-37. doi: 10.1086/518038. Epub 2007 May 3.

Abstract

Streptococcus pneumoniae fructose bisphosphate aldolase (FBA) is a cell wall-localized lectin. We demonstrate that recombinant (r) FBA and anti-rFBA antibodies inhibit encapsulated and unencapsulated S. pneumoniae serotype 3 adherence to A549 type II lung carcinoma epithelial cells. A random combinatorial peptide library expressed by filamentous phage was screened with rFBA. Eleven of 30 rFBA-binding phages inhibited 90% of S. pneumoniae adhesion to A549 cells. The insert peptide sequence of 9 of these phages matched the Flamingo cadherin receptor (FCR) when aligned against the human genome. A peptide comprising a putative FBA-binding region of FCR (FCRP) inhibited 2 genetically and capsularly unrelated pairs of encapsulated and unencapsulated S. pneumoniae strains from binding to A549 cells. Moreover, FCRP inhibited S. pneumoniae nasopharyngeal and lung colonization and, possibly, pneumonia development in the mouse intranasal inoculation model system. These data indicate that FBA is an S. pneumoniae adhesin and that FCR is its host receptor.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adhesins, Bacterial / isolation & purification*
  • Adhesins, Bacterial / metabolism
  • Animals
  • Antibodies, Bacterial / metabolism
  • Bacterial Adhesion / physiology*
  • Cadherins / isolation & purification
  • Cadherins / metabolism*
  • Cell Line, Tumor
  • Female
  • Fructose-Bisphosphate Aldolase / genetics
  • Fructose-Bisphosphate Aldolase / immunology*
  • Fructose-Bisphosphate Aldolase / metabolism
  • Humans
  • Mice
  • Mice, Inbred BALB C
  • Nasopharynx / microbiology
  • Pneumococcal Infections / microbiology*
  • Pneumococcal Infections / prevention & control
  • Rabbits
  • Recombinant Proteins / immunology
  • Recombinant Proteins / metabolism
  • Sequence Homology, Amino Acid
  • Streptococcus pneumoniae / genetics
  • Streptococcus pneumoniae / metabolism*
  • Time Factors
  • Virus Attachment

Substances

  • Adhesins, Bacterial
  • Antibodies, Bacterial
  • CELSR1 cadherin, human
  • Cadherins
  • Recombinant Proteins
  • Fructose-Bisphosphate Aldolase