Abstract
BACKGROUND: Despite the use of currently optimized lipofection conditions, including transfection in serum-depleted media, the efficiency of gene transfer is low and high transfection rates often induce cytotoxicity. A lipid formulation with transfection efficiency not inhibited by serum would provide an advance towards in vivo applications. METHODS: We explored the ability of the cationic lipid SH-14 to dimerize upon DNA and form lipoplexes, and potentially release nucleic acids in the intracellular reducing milieu. We investigated the critical micelle-forming concentration of SH-14 and its intrinsic toxicity, size and Zeta potential measurements, the in vitro cytotoxicity of SH-14/plasmid DNA lipoplexes and their ability to transfect cells. RESULTS: Among all the charge ratios (CR, + /-) tested, lipoplexes at CR 10 with a mean diameter of 295 nm and a surface charge of + 20 mV, exhibited the best compromise between transfection efficiency and tolerability. SH-14 presented the same cytotoxicity level whether alone or complexed in lipoplexes. Lipofections carried out in serum-free medium shared a transfection efficiency, on average, of 40% and a cytotoxicity of 38%. An increase of 73% in transfection efficiency and 24% in cell viability were obtained, extending lipofection over 48 h in complete-medium. Moreover, when serum concentration was increased from 10% to 50%, a three-fold increase in plasmid dose led to more than 72% of cells being transfected with almost no sign of cytotoxicity. CONCLUSIONS: Overall, SH-14 presents good potential as a novel transfection reagent to be used in the presence of serum.
Original language | English |
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Pages (from-to) | 637-645 |
Number of pages | 9 |
Journal | The Journal of Gene Medicine |
Volume | 10 |
Issue number | 6 |
Early online date | 14 Mar 2008 |
DOIs | |
Publication status | Published - 1 Jun 2008 |
Keywords
- analysis of variance
- animals
- COS cells
- cations
- cell line, tumor
- cercopithecus aethiops
- DNA
- dimerization
- fluorometry
- gene transfer techniques
- humans
- lipids
- micelles
- molecular structure
- rats
- triazines
- dimerizable function
- gene delivery
- lipoplex
- nonviral vector
- serum effect
- transfection