title: A new gene delivery formulation of polyethylenimine/DNA complexes coated with PEG conjugated fusogenic peptide.
abstract: A fusogenic peptide, KALA, was conjugated with poly(ethylene glycol) (PEG) for use as an endosome disruptive agent in the gene delivery formulation of polyethyleneimine (PEI). A maleimide terminated methoxy-PEG, a cysteine specific derivative, was reacted with KALA to produce a PEG-KALA conjugate. The conjugate was analyzed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry, and its hemolytic activity was determined relative to KALA. Positively charged PEG-KALA conjugate was coated onto the surface of negatively charged DNA/PEI complexes to form net positively charged PEG-KALA/DNA/PEI complexes. They were 200-400 nm in diameter with increasing amount of PEG-KALA, whereas DNA/PEI complexes coated with KALA aggregated to a great extent. This was because PEG chains surrounding the surface of the complexes suppressed the inter-particle interaction that was mediated by cationic KALA. Transfection efficiency progressively increased as the amount of PEG-KALA to be coated was increased, suggesting that fusogenic activity of KALA contributes to enhancing the level of gene expression.
authors.affiliation: Department of Biological Sciences, Korea Advanced Institute of Science and Technology, 305-701, Taejon, South Korea.
authors.forename: H
authors.initials: H
authors.lastname: Lee
authors.forename: J H
authors.initials: JH
authors.lastname: Jeong
authors.forename: T G
authors.initials: TG
authors.lastname: Park
mesh_terms: D000595:Amino Acid Sequence; D004247:DNA / Q000008:administration & dosage* / Q000737:chemistry; D004268:DNA-Binding Proteins / Q000008:administration & dosage*; D008969:Molecular Sequence Data; D010455:Peptides; D011092:Polyethylene Glycols / Q000008:administration & dosage*; D011094:Polyethyleneimine / Q000008:administration & dosage*
chemical_list: D004268:DNA-Binding Proteins; C105114:KALA amphipathic peptide; D010455:Peptides; D011092:Polyethylene Glycols; D011094:Polyethyleneimine; D004247:DNA