Enhanced gene delivery to human airway epithelial cells using an integrin-targeting lipoplex.
BACKGROUND
Current liposome-based delivery methods for cystic fibrosis (CF) gene therapy are limited by their poor efficiencies. One way to improve this is to use a receptor/ligand interaction to increase binding of the transfection complex with the target cell.


RESULTS
We have tested a synthetic peptide containing an alphav integrin-binding motif (arginine-glycine-aspartic acid, RGD) and a DNA-binding domain (polylysine) for enhancement of liposome-mediated gene delivery. We have shown that integrin proteins capable of binding the RGD motif are located on the apical surface of a polarized human bronchial epithelial cell line (16HBE). Luciferase gene transfer efficiency to subconfluent 16HBE cells was 10-200 times higher than gene transfer using either liposome or peptide alone. This peptide-mediated enhancement was observed at all cellular contact times including those as short as 1 min. Although the transfection efficiency is reduced when the 16HBE cells are grown as polarized monolayers, peptide-mediated enhancement of lipofection is maintained. Transfection with a lipopolyplex containing an RGE (arginine-glucine-glutamic acid) control peptide that cannot bind to the alphav integrin molecules, or competitive inhibition with antibodies against RGD-binding integrins, reduced gene transfer. Confocal microscopy indicated that the peptide increased plasmid delivery to the cell via receptor-mediated endocytosis.


CONCLUSIONS
These results indicate that integrin-binding peptides represent one way to enhance liposome-mediated gene delivery to pulmonary epithelia.
Scott
E S
ES
Department of Physiology, University of Cambridge, UK.
Wiseman
J W
JW
Evans
M J
MJ
Colledge
W H
WH
D000595:Amino Acid Sequence; D015703:Antigens, CD / Q000378:metabolism*; D001980:Bronchi / Q000166:cytology / Q000378:metabolism*; D002478:Cells, Cultured; D003550:Cystic Fibrosis / Q000628:therapy; D004847:Epithelial Cells / Q000378:metabolism; D018014:Gene Transfer Techniques; D017930:Genes, Reporter; D015316:Genetic Therapy; D006801:Humans; D007150:Immunohistochemistry; D039564:Integrin alphaV; D008024:Ligands; D009842:Oligopeptides / Q000378:metabolism; D010957:Plasmids; D011485:Protein Binding
D015703:Antigens, CD; D039564:Integrin alphaV; D008024:Ligands; D009842:Oligopeptides; C047981:arginyl-glycyl-aspartic acid