Gene-Transferring Efficiencies of Novel Diamino Cationic Lipids with Varied Hydrocarbon Chains

Abstract

Utilizing three biocompatible components, a series of novel cationic lipids has been chemically synthesized and tested for their gene-transferring capabilities in 293 transformed kidney cells and B16BL6 mouse melanoma cells. The synthesized cationic lipids consisting of a core of lysine and aspartic acid with hydrocarbon chains of varied length were assigned the acronyms DLKD (O,O'-dilauryl N-lysylaspartate), DMKD (O,O'-dimyristyl N-lysylaspartate), DPKD (O,O'-dipalmityl N-lysylaspartate), and DSKD (O,O'-distearyl N-lysylaspartate). The gene-transferring capabilities of these cationic lipids were found to be dependent on the hydrocarbon chain length. Under similar experimental conditions, the order of gene transfection efficiency was DMKD > DLKD > DPKD > DSKD. Addition of cholesterol or dioleoyl phosphatidylethanolamine (DOPE) as a colipid did not change this order. Colipid addition affected the transfection efficiency positively or negatively depending on the length of the cationic lipid acyl chain. On the whole, the length of the hydrophobic carbon chain was a major factor governing the gene-transferring capabilities of this series of cationic lipids. The observed differences in transfection efficiency may be due to differing binding affinities to DNA molecules as well as differences in the surface charge potential of the liposome-DNA complexes (lipoplexes) in the aqueous environment.

Preparation, Physicochemical Properties, and Transfection Activities of Tartaric Acid-Based Cationic Lipids as Effective Nonviral Gene Delivery Vectors

“…In addition, when N/P ratio was over 1 : 1, DNA was entirely compacted and protected in the cationic liposomes, the fluorescent in the corresponding lanes was absence because the staining reagent was inaccessible to stain DNA. 35,48) Optimization of Cationic Lipid/DOPE Ratios Neutral helper lipid DOPE plays an important role to form cationic liposomes. The appropriate addition of DOPE has been reported to increase the gene delivery efficiency of cationic liposomes.…”

“…1), while most of the backbone in earlier cationic lipids was classified into glycerol-type just as N- [2-[(1,5,10,14-tetraazatetradecane-1-yl) carbonylamino] ethyl]-N,Ndimethyl-2,3-bis(oleoyloxy)-1-propanaminium (DOSPA) and N- [2,3-dioleoyloxypropyl]-N,N,N-trimethylammonium chloride (DOTAP) 30,31) and cholesterol-type, such as 3β-[N-(N′,N′-dimethylaminoethyl) carbamoyl] cholesterol (DC-Chol). 32) Recently, phosphonate, 33) bile acid, 34) amino acids, 35,36) peptides, 37) pentaerythritol 38) and carbohydrate 39) were also successfully used as backbones in the design of cationic lipids, which can give a favorable gene delivery efficiency and low cytotoxicity.…”

Nature as a source of inspiration for cationic lipid synthesis

“…Novel amino acid-based cationic lipids incorporating lysine, histidine or arginine as the polar headgroup have been synthesized and tested for their transfection efficiencies (Heyes et al 2002;Kim et al 2004;Obata et al 2008). The diether lipids 21 and 22, with C 12 alkyl chains and a lysine or an arginine headgroup (Fig.…”

“…The formulations containing the histidinylated diether lipid 23 achieved a threefold increase in transfection efficiency compared with the control (Heyes et al 2002). The lysine-containing cationic lipids O,O 0 -dimyristyl N-lysylaspartate (DMKD) 24 and O,O 0 -dilauryl N-lysylaspartate (DLKD) 25 with, respectively, C 14 and C 12 alkyl chains, were reported to be more efficient in transfecting 293 and B16BL6 cell lines than 1,2-dioleoyl-3-trimethylammoniopropane (DOTAP), contrary to the C 16 and C 18 derivatives (Kim et al 2004). Moreover, the lysine-and arginine-type lipids 26a-c and 27a-c, having a glutamate backbone, exhibited higher gene expression efficiencies than Lipofectamine2000 TM , and this effect tended to increase with shorter alkyl chains.…”

Targeted gene therapy of LS174 T human colon carcinoma by anti-TAG-72 immunoliposomes

“…10 We have developed a new formulation of PILs, which can effectively deliver therapeutic genes to target cells in vivo. These immunoliposomes consist of cationic O,O 0 -dymyrisyl-N-lysyl aspartate (DMKD) 11 and anionic 1,2-distearoyl-sn-glycero-3-phosphoethanolamine-N-maleimide polyethylene glycol 2000 (DSPE-PEG 2000 -Mal) for coupling of antibody Fab 0 fragments. PEG provides for prolonged circulation, while conjugation of Fab 0 fragments of humanized monoclonal antibody, HuCC49, 12 specific for LS174 T human colon adenocarcinoma cells to PEG termini induces specific targeting.…”