Lipid transfection

Fig. 29 Optimum mole fraction of 0.5 for the helper DOPE in cationic lipid transfection formulations (reproduced from [35] copyright by the American Society for Biochemistry and Molecular Biology)...

Koynova R, Wang L, MacDonald RC (2006) An intracellular lamellar - nonlamellar phase transition rationalizes the superior performance of some cationic lipid transfection agents. Proc Nad Acad Sci USA 103 14373-14378... 

Due to the predominantly hydrophilic nature of PNAs they do not readily cross lipid membranes [93] and enter living cells [94]. Therefore in order to explore the ex vivo and in vivo potential of PNA as an antisense and/or antigene reagent, a number of different transfection protocols have been devised over recent years. 

Viruses are infectious particles formed by nucleic acid, proteins, and in some cases lipids. As viruses (for example, retro- and adenoviruses) transfer viral genes into cells with high efficiency, modified forms are sometimes used as vectors for gene transfer. However, procedures using virus-based vectors are often significantly more complicated and time-consuming than other transfection methods. In addition, viral vectors are potentially hazardous, and biological safety issues need to be considered carefully. Therefore, techniques that combine... 

Elroy-Stein, D., Bernstein, Y. and Groner, Y. (1986). Overproduction of human Cu/Zn-superoxide dismutase in transfected cells extenuation of paraquat-mediated cytotoxicity and enhancement of lipid peroxidation. EMBO J. 5, 615-622. 

The presence of a transporter can be assessed by comparing basolateral-to-apical with apical-to-basolateral transport of substrates in polarized cell monolayers. If P-gp is present, then basolateral-to-apical transport is enhanced and apical-to baso-lateral transport is reduced. Transport experiments are in general performed with radioactively labeled compounds. Several studies have been performed with Caco-2 cell lines (e.g. Ref. [85]). Since Caco-2 cells express a number of different transporters, the effects measured are most probably specific for the ensemble of transporters rather than for P-gp alone. P-gp-specific transport has been assayed across confluent cell layers formed by polarized kidney epithelial cells transfected with the MDR1 gene [86], Figure 20.11 shows experimental data obtained with these cell lines. A rank order for transport called substrate quality was determined for a number of compounds [86]. The substrate quality is a qualitative estimate, but nevertheless allows an investigation of the role of the air/water (or lipid/water) partition coefficient, log Kaw, for transport as seen in Fig. 20.11(A). For most of the compounds, a linear correlation is observed between substrate quality and log Kaw- However, four compounds are not transported at all despite their distinct lipophilicity. A plot of the substrate quality as a function of the potential of a... 

The production of CLS by the melt dispersion technique is based on the melting of the lipid core material together with the lipophilic agent (i.e., phospholipids). Afterward, a warm aqueous solution is added to the molten material and is mixed by various methods (i.e., mechanical stirring, shaking, sonication, homogenization). Then the preparation is rapidly cooled until lipid solidification and the formation of particle dispersion. This method was used by Olbrich et al. [19] to produce the cationic solid lipid nanoparticles to use as novel transfection agent. 

Bennett, M.J., Aberle A.M., Balasubramaniam R.P., Malone, J.G., Malone, R.W., and Nantz, M.H., Cationic lipid-mediated gene delivery to murine lung correlation of lipid hydration with in vivo transfection activity, Journal of Medicinal Chemistry, 1997, 40, 4069 1078. 

Olbrich, C., Bakowsky, U., Lehr, C.M., Muller, R.H., and Kneuer, C., Cationic solid-lipid nanoparticles can efficiently bind and transfect plasmid DNA, Journal of Controlled Release, 2001, 77, 345-355. 

Nicholson, A.C., Friede, S., Pearce, A., and SUverstein, R.L., 1995, Oxidized LDL binds to CD36 on human monocyte-derived macrophages and transfected ceU Unes Evidence implicating the lipid moiety of the lipoprotein as the binding Aie.,Arterioscl. Tromb. Vase. Biol. 15 269-275. 

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