Gene delivery system transfection efficiency

The assembly of NLS in peptide-based gene delivery systems has been achieved by the non-covalent binding of plasmid to either free NLS embedded with polyplexes or to NLS linked to a cationic sequence, such as (PKKKRKV)4-K2o (Table 16.7), AKRARLSTSFNPVYPYEDES-K20 (Table 16.7) or H9-2 sequence (nls-H9-2) (Table 16.4). With nls-H9-2, the transfection efficiency with a formulation containing... 

Anti-deoxyribonucleic acid autoantibodies from human and mice suffering from Lupus erythematosus can penetrate into cells and accumulate in the cell nucleus. Based on the characteristics of a mi-ON A autoantibodies, VAYISRGGVSTYYSDTVKGRFTRQKYNKRA peptide (P3), which exhibits a-helix, has been used as a vector for the intracytoplasmic and intranuclear translocation of macromolecules (Table 16.7) (Avrameas et al., 1998, 1999). P3 shares similar capabilities with Antenapedia peptide (Derossi et al., 1994), but in contrast P3 operates only at 37 °C by an energy dependent mechanism. P3 linked to a 19 lysine residue sequence (K19-P3) forms complexes with plasmid DNA. Efficient transfection of mouse 3T3 cells and hamster lung CCL39 cells were obtained with these complexes. This transfection was not impaired by the presence of serum and did not require helper molecules such as chloroquine. These observations suggest that peptides from cell specific anti-DNA autoantibodies may represent a source of peptide-based gene delivery system with different specificities. 

Wong K, Sun G, Zhang X et al (2006) PEI-g-chitosan, a novel gene delivery system with transfection efficiency comparable to polyethylenimine in vitro and after liver administration in vivo. Bioconjug Chem 17 152-158... 

The transfection efficiency with the gene delivery system by sonoporation mechanism using BLs and US was higher than conventional lipofection method with Lipofectin and Lipofectamine 2000. Therefore, it is expected that this system might be an effective nonviral gene delivery system. 

To develop an efficient gene delivery system, it seems necessary to understand the extra- and intracellular processes involved in the overall transfection mechanism. This will lead to understanding the mechanism, which is necessary for developing novel lipid-based non-viral vectors. For this purpose, cationic liposomes and pDNA are used widely to understand the cellular mechanism involved in the transfection (Fig. 13.3). 

Liu et al. presented the synthesis of polyamidoamine-functionalized mul-tiwalled carbon nanotubes (PAA-g-MWNTs) and their application as a novel gene delivery system. The PAA-g-MWNTs showed comparable or even higher transfection efficiency than PAA and PEI at optimal w/w ratio. Intracellular trafficking of Cy3-labeled pGL-3 indicated that a large number of Cy3-labeled pGL-3 were attached to the nucleus membrane, the majority of which was localized in the nucleus after incubation with cells for 24 h (Figure 3.20). 

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