US EPA

5916839 

Journal Article 

Plasmid size up to 20 kbp does not limit effective in vivo lung gene transfer using compacted DNA nanoparticles 

Fink, TL; Klepcyk, PJ; Oette, SM; Gedeon, CR; Hyatt, SL; Kowalczyk, TH; Moen, RC; Cooper, MJ 

2006 

1 

Gene Therapy
ISSN: 0969-7128
EISSN: 1476-5462 

13 

13 

1048-1051 

English 

16525478 

10.1038/sj.gt.3302761 

WOS:000238418900008 

Nanoparticles consisting of single molecules of DNA condensed with polyethylene glycol-substituted lysine 30-mers efficiently transfect lung epithelium following intrapulmonary administration. Nanoparticles formulated with lysine polymers having different counterions at the time of DNA mixing have distinct geometric shapes: trifluoroacetate or acetate counterions produce ellipsoids or rods, respectively. Based on intracytoplasmic microinjection studies, nanoparticle ellipsoids having a minimum diameter less than the 25 nm nuclear membrane pore efficiently transfect non-dividing cells. This 25 nm size restriction corresponds to a 5.8 kbp plasmid when compacted into spheroids, whereas the 8-11 nm diameter of rod-like particles is smaller than the nuclear pore diameter. In mice, up to 50% of lung cells are transfected after dosing with a rod-like compacted 6.9 kbp lacZ expression plasmid, and correction of the CFTR chloride channel was observed in humans following intranasal administration of a rod-like compacted 8.3 kbp plasmid. To further investigate the potential size and shape limitations of DNA nanoparticles for in vivo lung delivery, reporter gene activity of ellipsoidal and rod-like compacted luciferase plasmids ranging in size between 5.3 and 20.2 kbp was investigated. Equivalent molar reporter gene activities were observed for each formulation, indicating that microinjection size limitations do not apply to the in vivo gene transfer setting.