Plasmid DNA vectors offer the potential of safe gene therapy avoiding viral vector-mediated toxicity and immunogenicity. As plasmid DNA is bacterial in origin, presence of bacterial lipopolysaccharide (LPS) or unmethylated CpG dinucleotides may stimulate host innate immunity.
Diabetes Research Group, Institute of Cell and Molecular Biosciences, University of Newcastle upon Tyne, Framlington Place, Newcastle upon Tyne NE2 4HH, UK.