Assessment of delivery parameters with the multi-electrode array for development of a DNA vaccine against Bacillus anthracis

Old Dominion University, Center for Bioelectrics, 4211 Monarch Way, Suite 300, Norfolk, VA 23508, USA. Electronic address: .
Bioelectrochemistry (Amsterdam, Netherlands) (Impact Factor: 4.17). 04/2013; 94C:1-6. DOI: 10.1016/j.bioelechem.2013.04.004
Source: PubMed


Gene electrotransfer (GET) enhances delivery of DNA vaccines by increasing both gene expression and immune responses. Our lab has developed the multi-electrode array (MEA) for DNA delivery to skin. The MEA was used at constant pulse duration (150ms) and frequency (6.67Hz). In this study, delivery parameters including applied voltage (5-45V), amount of plasmid (100-300μg), and number of treatments (2-3) were evaluated for delivery of a DNA vaccine. Mice were intradermally injected with plasmid expressing Bacillus anthracis protective antigen with or without GET and αPA serum titers measured. Within this experiment no significant differences were noted in antibody levels from varying dose or treatment number. However, significant differences were measured from applied voltages of 25 and 35V. These voltages generated antibody levels between 20,000 and 25,000. Serum from animals vaccinated with these conditions also resulted in toxin neutralization in 40-60% of animals. Visual damage was noted at MEA conditions of 40V. No damage was noted either visually or histologically from conditions of 35V or below. These results reflect the importance of establishing appropriate electrical parameters and the potential for the MEA in non-invasive DNA vaccination against B. anthracis.

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    • "The vaccination course consisted of two intradermal injections into the skin of the back near the base of the tail. Immediately after the plasmid or FITC-dextran administration, a conducting gel and an electrode were placed over the injection site and voltage was set up according to previously described protocols (2 pulses, 1125 V/cm 50 í µí¼‡s, and 8 pulses, 275 V/cm 10 msec) [20]. Electrodes conslehisted of two parallel lamellae at 6–8 mm distance. "
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