title: Nebulisation of receptor-targeted nanocomplexes for gene delivery to the airway epithelium.
abstract: BACKGROUND
  Gene therapy mediated by synthetic vectors may provide opportunities for new treatments for cystic fibrosis (CF) via aerosolisation. Vectors for CF must transfect the airway epithelium efficiently and not cause inflammation so they are suitable for repeated dosing. The inhaled aerosol should be deposited in the airways since the cystic fibrosis transmembrane conductance regulator gene (CFTR) is expressed predominantly in the epithelium of the submucosal glands and in the surface airway epithelium. The aim of this project was to develop an optimised aerosol delivery approach applicable to treatment of CF lung disease by gene therapy.
  
  
  METHODS
  The vector suspension investigated in this study comprises receptor-targeting peptides, cationic liposomes and plasmid DNA that self-assemble by electrostatic interactions to form a receptor-targeted nanocomplex (RTN) of approximately 150 nm with a cationic surface charge of +50 mV. The aerodynamic properties of aerosolised nanocomplexes produced with three different nebulisers were compared by determining aerosol deposition in the different stages of a Next Generation Pharmaceutical Impactor (NGI). We also investigated the yield of intact plasmid DNA by agarose gel electrophoresis and densitometry, and transfection efficacies in vitro and in vivo.
  
  
  RESULTS
  RTNs nebulised with the AeroEclipse II BAN were the most effective, compared to other nebulisers tested, for gene delivery both in vitro and in vivo. The biophysical properties of the nanocomplexes were unchanged after nebulisation while the deposition of RTNs suggested a range of aerosol aerodynamic sizes between 5.5 µm-1.4 µm cut off (NGI stages 3-6) compatible with deposition in the central and lower airways.
  
  
  CONCLUSIONS
  RTNs showed their ability at delivering genes via nebulisation, thus suggesting their potential applications for therapeutic interventions of cystic fibrosis and other respiratory disorders.
authors: Wolfson Centre for Gene Therapy of Childhood Disease, UCL Institute of Child Health, University College London, London, United Kingdom.
authors: Maria D I
authors: MD
authors: Manunta
authors: Robin J
authors: RJ
authors: McAnulty
authors: Aristides D
authors: AD
authors: Tagalakis
authors: Stephen E
authors: SE
authors: Bottoms
authors: Frederick
authors: F
authors: Campbell
authors: Helen C
authors: HC
authors: Hailes
authors: Alethea B
authors: AB
authors: Tabor
authors: Geoffrey J
authors: GJ
authors: Laurent
authors: Christopher
authors: C
authors: O'Callaghan
authors: Stephen L
authors: SL
authors: Hart
mesh_terms: D003550:Cystic Fibrosis / Q000628:therapy; D004848:Epithelium / Q000378:metabolism; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D058990:Molecular Targeted Therapy; D053761:Nanocomposites / Q000008:administration & dosage; D009330:Nebulizers and Vaporizers; D010957:Plasmids / Q000008:administration & dosage; D020545:Respiratory Mucosa / Q000378:metabolism*; D014162:Transfection