title: A novel model to study bacterial adherence to the transplanted airway: inhibition of Burkholderia cepacia adherence to human airway by dextran and xylitol.
abstract: BACKGROUND
  Lung infection with Burkholderia cepacia complex before lung transplantation in patients with cystic fibrosis is a major risk factor for decreased post-operative survival rates compared with those of patients colonized with the more common opportunistic pathogen Pseudomonas aeruginosa. Because adherence to mucosal surfaces is an important initial step in infection, we investigated the use of non-toxic neutral polysaccharides and a sugar alcohol to prevent adherence of B cepacia complex to allograft airway epithelium.
  
  
  METHODS
  We used human airway explants prepared from donor tracheobronchial tissue to test the effect of dextrans and xylitol in inhibiting the binding of Burkholderia cepacia complex. We used immunofluorescence and electron microscopy to determine the distribution of bacteria in the explants.
  
  
  RESULTS
  Burkholderia cepacia complex bound to the explants and was found only in the surface mucus layer. Dextran 40 kd applied before adding the bacteria decreased the number of bound organisms by 80% to 99%. Smaller molecular mass dextrans (4 and 20 kd) were ineffective. Xylitol inhibited bacterial binding by 67% to 85%. Both agents seemed to decrease the thickness of the surface mucus, suggesting that they may indirectly inhibit bacterial binding by removing adherent surface mucus.
  
  
  CONCLUSIONS
  Treating donor lungs with dextran 40 kd or xylitol before (and possibly after) surgery may inhibit the adherence of Burkholderia cepacia complex to airways and may prevent or decrease subsequent infection of the allografts.
authors.affiliation: Division of Structural Biology and Biochemistry, Hospital for Sick Children, Toronto, Ontario, Canada.
authors.forename: Umadevi
authors.initials: U
authors.lastname: Sajjan
authors.forename: Jorge
authors.initials: J
authors.lastname: Moreira
authors.forename: Mingyao
authors.initials: M
authors.lastname: Liu
authors.forename: Atul
authors.initials: A
authors.lastname: Humar
authors.forename: Cecilia
authors.initials: C
authors.lastname: Chaparro
authors.forename: Janet
authors.initials: J
authors.lastname: Forstner
authors.forename: Shaf
authors.initials: S
authors.lastname: Keshavjee
mesh_terms: D001422:Bacterial Adhesion / Q000187:drug effects*; D001980:Bronchi / Q000382:microbiology*; D019121:Burkholderia Infections / Q000382:microbiology / Q000517:prevention & control; D042602:Burkholderia cepacia complex / Q000187:drug effects* / Q000502:physiology; D003911:Dextrans / Q000494:pharmacology*; D006801:Humans; D066298:In Vitro Techniques; D016040:Lung Transplantation; D008855:Microscopy, Electron, Scanning; D046529:Microscopy, Electron, Transmission; D008856:Microscopy, Fluorescence; D009894:Opportunistic Infections / Q000382:microbiology / Q000517:prevention & control; D014132:Trachea / Q000382:microbiology*; D014993:Xylitol / Q000494:pharmacology*
chemical_list: D003911:Dextrans; D014993:Xylitol