Companies: Osivax
Nucleic acid based immunization exhibits a number of advantages. For example, the manufacture of nucleic acid based vaccines is straight forward, relatively inexpensive.
DNA Vaccines
Potential advantages: DNA based vaccines are stable for long-term storage. DNA vaccines offer advanatages overy many of vaccines. Since the antigen is produced with mammalin post translational modification, conformation and oligomerization, it is more likely to be similar or identical to the wild type protein produced by viral infection than recombinant or chemically modified proteins. However, this distinction may turn out to be a disadvantage for the application of bacterial antigens, since non-native post translational modification may result in reduced immunogenicity. In addition, viral surface proteins are not highly organized in the absence of matrix proteins.
DNA vaccine can induce humoral and cellular immunity and it also saves labour and time because of the siplicity of oepration (Zhang, J Gene Med 2007 9, 715-726).
Potential disadvantages: DNA based vaccines exhibit a variety of potential safety risks such as induction of anti-DNA antibodies, and potential integration of the transgene into the host genome. This may lead to the inactivation of cellular genes, an uncontrollable long term expression of the transgene, or oncogenesis, and thus, is generally not applicable for tumor-associated antigens with oncogenic potential such as erb-B2.
DNA vaccination in avian species:
Duan (US2005/0208628) dicloses a pcoress for producing antibodies to an antigen in an avian species by delivering a DNA dequence encoding the antigen operatively linke to a promoter capable of directing expression of the antigen in the avian species and recovering antibodies from the avian species. Preferably the avian species being vaccinated is a chicken or quail and the antibodies are recovered from egg yolk. The use of chicken offers a number of advantages such as cost.
RNA Vaccines (see outline)