Photochemically enhanced transduction of polymer-complexed adenovirus targeted to the epidermal growth factor receptor.
BACKGROUND
The development of methods for specific delivery of genes into target tissues is an important issue for the further progress of gene therapy. Biological and physical targeting techniques may be combined to redirect gene therapy vectors to specific cells and enhance gene transfer.


METHODS
The polymer poly(2-(dimethylamino)ethyl methacrylate) (pDMAEMA) was conjugated with avidin or poly(ethylene glycol) (PEG) and complexed with adenovirus serotype 5 (Ad5). Targeting of polymer-coated Ad5 to the epidermal growth factor receptor (EGFR) was accomplished by the binding of biotin-EGF to pDMAEMA-avidin. A photochemical treatment procedure using photosensitizer and light was applied to increase transduction with EGFR-targeted viral complexes.


RESULTS
pDMAEMA-avidin efficiently enhanced transduction through unspecific viral uptake into cells, while pDMAEMA-PEG provided charge shielding of the complexes and increased the specificity to EGFR when biotin-EGF ligands were used. Transduction of PEG-containing, EGFR-targeted viral complexes was inhibited by 66% in coxsackie and adenovirus receptor (CAR)-deficient RD cells and by 47% in CAR-expressing DU 145 cells in receptor antibody experiments. The photochemical treatment had a substantial effect on transduction, enhancing the percentage of reporter gene positive cells from 20% to 75% of the total viable RD cell population and from 10% to 70% in DU 145 cells.


CONCLUSIONS
Photochemical treatment of cells infected with targeted viral vectors exhibiting a neutral surface charge is a potent method for enhancing transgene expression.
Bonsted
Anette
A
Department of Radiation Biology, Institute for Cancer Research, Rikshospitalet-Radiumhospitalet HF, Montebello, N-0310 Oslo, Norway. anettbo@ulrik.uio.no
Engesaeter
Birgit Øvstebø
BØ
Høgset
Anders
A
Maelandsmo
Gunhild M
GM
Prasmickaite
Lina
L
D'Oliveira
Christine
C
Hennink
Wim E
WE
van Steenis
Jan Hein
JH
Berg
Kristian
K
D000256:Adenoviridae / Q000235:genetics; D001360:Avidin; D004337:Drug Carriers; D066246:ErbB Receptors / Q000096:biosynthesis / Q000235:genetics*; D005260:Female; D020869:Gene Expression Profiling; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D008297:Male; D008689:Methacrylates; D009757:Nylons; D010777:Photochemistry; D011092:Polyethylene Glycols; D011471:Prostatic Neoplasms / Q000473:pathology; D018233:Rhabdomyosarcoma, Embryonal / Q000473:pathology; D012509:Sarcoma / Q000473:pathology; D014161:Transduction, Genetic; D014407:Tumor Cells, Cultured; D014594:Uterine Neoplasms / Q000473:pathology
D004337:Drug Carriers; D008689:Methacrylates; D009757:Nylons; C407037:poly(2-(dimethylamino)ethyl methacrylate); D001360:Avidin; D011092:Polyethylene Glycols; D066246:ErbB Receptors