title: Pseudomonas aeruginosa adherence to human basement membrane collagen in vitro.
abstract: The mechanisms for Pseudomonas aeruginosa colonisation in the airways of patients with bronchiectasis and cystic fibrosis are poorly understood. P. aeruginosa could evade mucociliary clearance by adhering to the basement membrane at areas denuded of intact respiratory epithelium. The authors have developed an in vitro model to study P. aeruginosa adherence to human basement membrane type-IV collagen by using scanning electron microscopy. P. aeruginosa adherence density was determined as the number of P. aeruginosa per 20 microscope fields (2,000x) to log inocular size after incubation at 37 degrees C for 45 min. The presence of phytohaemagglutinin (PHA)-E, which binds specifically to D-galactose-beta1-4-D-N-acetylglucosamine, significantly reduced P. aeruginosa adherence density compared with control. The presence of heparin and calcium also significantly reduced P. aeruginosa adherence density. P. aeruginosa adherence was not affected by the presence of proline, trans-hydroxyproline, glycine, galactose, N-acetylneuraminic acid, N-acetylglucosamine or Arachis hypogea. Pseudomonas aeruginosa adherence probably acts via recognition of the D-galactose-beta1-4-D-N-acetylglucosamine sequence on type-IV collagen and this process could be inhibited by heparin and calcium. As persistent Pseudomonas aeruginosa colonisation is detrimental to patients with cystic fibrosis and bronchiectasis and there is currently no effective treatment for its eradication, these results could lead to novel therapy for persistent Pseudomonas aeruginosa infection.
authors.affiliation: University Dept of Medicine, Queen Mary Hospital, The University of Hong Kong, Pokfulam, Hong Kong SAR, China. kwttsang@hkucc.hku.hk
authors.forename: K W
authors.initials: KW
authors.lastname: Tsang
authors.forename: D K
authors.initials: DK
authors.lastname: Shum
authors.forename: S
authors.initials: S
authors.lastname: Chan
authors.forename: P
authors.initials: P
authors.lastname: Ng
authors.forename: J
authors.initials: J
authors.lastname: Mak
authors.forename: R
authors.initials: R
authors.lastname: Leung
authors.forename: I H
authors.initials: IH
authors.lastname: Shum
authors.forename: G C
authors.initials: GC
authors.lastname: Ooi
authors.forename: G L
authors.initials: GL
authors.lastname: Tipoe
authors.forename: W K
authors.initials: WK
authors.lastname: Lam
mesh_terms: D000596:Amino Acids / Q000494:pharmacology; D001422:Bacterial Adhesion / Q000187:drug effects / Q000502:physiology*; D001485:Basement Membrane / Q000187:drug effects / Q000503:physiopathology* / Q000648:ultrastructure; D001987:Bronchiectasis / Q000503:physiopathology*; D002241:Carbohydrates / Q000494:pharmacology; D024141:Collagen Type IV / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D015169:Colony Count, Microbial; D003550:Cystic Fibrosis / Q000503:physiopathology*; D006801:Humans; D066298:In Vitro Techniques; D007477:Ions / Q000494:pharmacology; D037102:Lectins / Q000494:pharmacology; D008855:Microscopy, Electron, Scanning; D011550:Pseudomonas aeruginosa / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure
chemical_list: D000596:Amino Acids; D002241:Carbohydrates; D024141:Collagen Type IV; D007477:Ions; D037102:Lectins