Delivery

Note that the method of delivery determines the dose of DNA required to raise an effective immune response. The two most popular approaches are injection of DNA in saline, using a standard hypodermic needle, and a gene gun delivery. In gene gun delivery, pDNA that has been adsorbed onto gold or tungsten nanoparticles are ballistic ally accelerated into the target cells, basically bombarding them, using compressed helium as the accelerant^[10]. Whilst uptake is efficient using the gene delivery method, the opposite is the case for saline injection.

In order to optimise the potency of DNA vaccines in saline injections, electroporation is often used to increase host cell transfection rate^[11]. This can be carried out by simply using hypertonic solutions of saline or sucrose. An alternative method (when injecting intramuscularly) is using a myotoxin such as bupivacaine to temporarily damage muscle fibres.