Plasmid DNA is becoming increasingly attractive for the delivery of therapeutic genes into human cells. The success of gene therapy depends on the efficient insertion of therapeutic genes at the appropriate chromosomal target sites within the human genome, without causing cell injury, oncogenic mutations or an immune response. The construction of plasmid vectors for this purpose is simple and straightforward. Custom-designed zinc finger nucleases that combine the non-specific cleavage domain of FokI endonuclease with zinc finger proteins offer a general way to deliver a site-specific double strand break to the genome, and stimulate local homologous recombination by several orders of magnitude. This makes targeted gene correction or genome editing a viable option in human cells. These plasmids can be used to transiently express zinc finger nucleases to target a double strand break to a specific gene locus in human cells; they offer an excellent way for targeted delivery of the therapeutic genes to a pre-selected chromosomal site. The plasmid-based approach has the potential to circumvent all the problems associated with the viral delivery of therapeutic genes.

from Kandavelou and Chandrasegaran in Plasmids: Current Research and Future Trends

Labels: plasmids, therapy