Gene expression in lung and liver after intravenous infusion of polyethylenimine complexes of Sleeping Beauty transposons.
Two methods of systemic gene delivery have been extensively explored, using the mouse as a model system: hydrodynamic delivery, wherein a DNA solution equivalent in volume to 10% of the mouse weight is injected intravenously in less than 10 sec, and condensation of DNA with polyethylenimine (PEI) for standard intravenous infusion. Our goal in this study was to evaluate quantitatively the kinetics of gene expression, using these two methods for delivery of Sleeping Beauty transposons. Transposons carrying a luciferase expression cassette were injected into mice either hydrodynamically or after condensation with PEI at a PEI nitrogen-to-DNA phosphate ratio of 7. Gene expression in the lungs and liver after hydrodynamic delivery resulted in exponential decay with a half-life of about 35-40 hr between days 1 and 14 postinjection. The decay kinetics of gene expression after PEI-mediated gene delivery were more complex; an initial decay rate of 6 hr was followed by a more gradual loss of activity. Consequently, the liver became the primary site of gene expression about 4 days after injection of PEI-DNA, and by 14 days expression in the liver was 10-fold higher than in the lung. Overall levels of gene expression 2 weeks postinjection were 100- to 1000-fold lower after PEI-mediated delivery compared with hydrodynamic injection. These results provide insight into the relative effectiveness and organ specificity of these two methods of nonviral gene delivery when coupled with the Sleeping Beauty transposon system.
Podetz-Pedersen
Kelly M
KM
Beckman Center for Transposon Research, Center for Genome Engineering, Institute of Human Genetics, and Department of Genetics, Cell Biology, and Development, University of Minnesota, Minneapolis, MN 55455, USA.
Bell
Jason B
JB
Steele
Terry W J
TW
Wilber
Andrew
A
Shier
W Thomas
WT
Belur
Lalitha R
LR
McIvor
R Scott
RS
Hackett
Perry B
PB
D000818:Animals; D004251:DNA Transposable Elements / Q000235:genetics*; D005260:Female; D018014:Gene Transfer Techniques; D015316:Genetic Therapy / Q000379:methods; D007262:Infusions, Intravenous; D008099:Liver / Q000378:metabolism*; D008156:Luciferases / Q000235:genetics / Q000378:metabolism*; D008168:Lung / Q000378:metabolism*; D051379:Mice; D008810:Mice, Inbred C57BL; D009928:Organ Specificity; D011094:Polyethyleneimine / Q000008:administration & dosage / Q000737:chemistry; D019076:Transgenes / Q000235:genetics; D019895:Transposases / Q000008:administration & dosage / Q000737:chemistry / Q000235:genetics
D004251:DNA Transposable Elements; D011094:Polyethyleneimine; D008156:Luciferases; D019895:Transposases; C494471:sleeping beauty transposase, human