Nonviral gene delivery systems features

This section will describe the features and clinical applications for each gene delivery system. The description will start with a common feature of both viral and nonviral gene delivery systems, the expression cassette for the therapeutic protein. 

TABLE 15.2. Key features of viral and nonviral gene delivery systems... 

Nonviral gene transfer systems are based on a variety of technologies that employ physical/chemical means to deliver genes [6], These technologies include direct plasmid injection, bombardment with DNA coated microprojectiles, and DNA complexed with liposomes or polymers. Some nonviral transfection techniques are too inefficient (e.g., coprecipitation of DNA with calcium phosphate [7], DNA complexed with diethylaminoethyl (DEAE)-dextran [8], electroporation [9]), or laborious (e.g., microinjection of DNA [ 10 ]) for clinical use. Only those gene delivery systems (viral and nonviral) with potential for clinical application are discussed in this chapter. The main features of these technologies (Table 18.3) are described and specific examples of their applications highlighted. 

The use of responsive vectors highlights the multifaceted and complex nature of these cationic lipid vectors and the supramolecular structures they form with DNA. By varying composition, chain lengths, linkers, and various properties, the lipoplex phase can be tailored to improve gene delivery. The research featured in this chapter has shown how the use of responsive nonviral vectors can enhance endosomal escape of the lipoplex and release of DNA from the lipoplex system, subsequently affecting gene transfer. 

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