Liposomes Enhance Delivery and Expression of an RGD-oligolysine Gene Transfer Vector in Human Tracheal Cells

Gene Ther. 1998 Nov;5(11):1488-98. doi: 10.1038/


Nonviral gene delivery systems consist predominantly of lipoplexes or receptor-targeting and nontargeting polyplexes. We examined integrin-mediated gene delivery using an Arg-Gly-Asp/oligo-L-lysine ([K]16RGD) cyclic peptide and investigated its gene transfer efficiency when associated with a cationic liposome. We demonstrated that human cystic fibrosis and noncystic fibrosis tracheal epithelial cells in culture express integrins that recognise the RGD integrin-binding motif. We found a 10-fold (P < 0.01) increased expression of a luciferase encoding plasmid in these cells when complexing the plasmid to the [K]16RGD peptide as compared with plasmid alone. This increase was specific to the [K]16RGD peptide since neither a [K]16RGE nor a [K]16 peptide gave a comparable increase. Expression was further enhanced 30-fold (P < 0.01) with lipofectamine and the ratio of DNA/peptide/lipofectamine was critical for specificity and expression. Fluorescence and radioactive labelling of the complex showed that the [K]16RGD peptide increased the endocytic uptake of DNA into cells. The cell association of both DNA and peptide increased even further with lipofectamine. Confocal microscopy showed that the [K]16RGD peptide and the DNA internalised together within 30 min and localised to vesicles in the perinuclear region. These results show that an integrin-binding ligand can deliver genetic material to airway cells and that a cationic liposome can enhance the efficacy of this nonviral vector system.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Cation Exchange Resins
  • Cells, Cultured
  • Cystic Fibrosis / therapy*
  • Gene Expression
  • Gene Transfer Techniques*
  • Genetic Therapy / methods*
  • Genetic Vectors*
  • Humans
  • Integrins / metabolism
  • Lipids
  • Liposomes
  • Luciferases / genetics
  • Microscopy, Confocal
  • Oligopeptides
  • Receptors, Immunologic
  • Statistics, Nonparametric
  • Trachea / metabolism*


  • Cation Exchange Resins
  • Integrins
  • Lipids
  • Lipofectamine
  • Liposomes
  • Oligopeptides
  • Receptors, Immunologic
  • arginyl-glycyl-aspartic acid
  • Luciferases