Plasmid DNA vectors

Carlisle RC, Bettinger T, Ogris M, Hale S, Mautner V, Seymour LW (2001) Adenovirus hexon protein enhances nuclear delivery and increases transgene expression of polyethy-lenimine/plasmid DNA vectors. Mol Ther 4 473 183... 

Tripathy, S.K., Svensson, E.C., Black, H.B., Goldwasser, E., Margalith, M., Hobart, P.M. et al. (1996) Long-term expression of erythropoietin in the systemic circulation of mice after intramuscular injection of a plasmid DNA vector. Proc. Natl. Acad. Sci. USA, 93, 10876-10880. 

An alternative method for introducing a plasmid DNA vector is to use liposomes. As they are composed of aqueous vesicles surrounded by a phospholipid bilayer, liposomes allow encapsulation and transportation of many substances, both hydrophilic and lipophilic, along with the plasmid. Liposomes also allow molecules such as antibodies, proteins, and sugars to be incorporated into their surface, to target them to specific sites. Due to the structural versatility shown by these systems, the chances of effective transfection may be increased by changes in the lipid composition, which may alter the superficial charge or the vesicle size (Bramwell and Perrie, 2005). Cationic liposomes have wide applications in gene transfection. 

On the other hand, from the technological point of view, several barriers have already been overcome, allowing production of viral or plasmid DNA vectors at a cost that enables clinical application. Safe manufacturing processes are already available, and the production capacity for these systems is easily accessible worldwide. 

Vector Any DNA structure that is used to transfer DNA into an organism most commonly used are plasmid DNA vectors or viruses. 

The transport of the therapeutic transgenes toward the nuclei of the target cells can be carried out both by viral [19] and nonviral vectors such as plasmid DNA [20]. Plasmid DNA molecules are extra-chromosomal carriers of genetic information that have the ability to replicate autonomously. These vectors constitute an attractive gene transfer system because they are safer and easier to produce when compared with viral vectors [20-22]. However, plasmid DNA vectors are less effective in transfecting cells when compared with viral vectors, which have a natural ability to deliver and express their genes in a wide variety of cell types and tissues [11,23]. 

Recombinant DNA technology in protein engineering can tether the functionality of the protein. Figure 9.1 summarizes the process of protein synthesis via recombinant technology. After construction of the gene library, an individual gene is incorporated into the circular plasmid DNA vector, which can be used to transform an... 

YewNS, Zhao H, Wu IH, Song A, Tousignant JD, Przybylska M, Cheng SH. Reduced inflammatory response to plasmid DNA vectors by elimination and inhibition ofimmunostimulatDiyCpG motifs. Mol Ther2000 l(3) 255-262. 

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