DNA Vaccines

Scope

This program aims at improving DNA vaccines to facilitate their commercial application

Research outline

Increasing in vivo expression of DNA vaccines

Jean-Pierre Scheerlinck and Hung-Hsun Yen

DNA vaccination represents a novel approach to vaccine development but suffers from poor immunogenicity in larger species. One of the limiting factors in DNA vaccine immunogenicity is the low level of gene expression from the injected plasmid. In vivo electroporation allows for a dramatic increase of gene expression at the site of immunisation. The effect of increasing in vivo expression levels on immunogenicity of DNA vacciens is currently being investigated.

Genetic adjuvants for DNA vaccines

Hung-Hsun Yen and Jean-Pierre Scheerlinck

DNA vaccination could become a safe and cost-effective alternative to control fasciolosis and gastrointestinal nematodes in ruminants. We are investigating ways of improving immunogenicity to DNA vaccination in sheep by molecular adjuvants including cytokines and trafficking molecules, which enhance antigen presentation to the immune system. In addition we are assessing the potential of CpG motifs as DNA vaccine immuno-modulators in sheep.

Muscle cells expressing enhanced green fluorescent protein (EGFP) following injection (Left) and electroporation (Right) of DNA encoding EGFP.

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Key publications

• Scheerlinck J.-P. Y., J. Karlis, T. E. Tjelle, P. J. A. Presidente, I. Mathiesen and S. E. Newton (2004). In vivo electroporation improves immune responses to DNA vaccination in sheep. Vaccine 22(13-14):1820-1825.
• De Rose R., J. Tennent, P. McWaters, P. J. Chaplin, P. R. Wood, W. Kimpton, R. Cahill and J.-P. Y. Scheerlinck (2002). Efficacy of DNA vaccination by different routes of immunisation in sheep. Vet. Immunol. Immunopathol. 90(1-2):55-63.
• Scheerlinck J.-P. Y., G. Casey, P. McWaters, J. Kelly, D. Woollard, M. W. Lightowlers, J. M. Tennent and P. J. Chaplin (2001). The immune response to a DNA vaccine can be modulated by co-delivery of cytokine genes using a DNA prime-protein boost strategy. Vaccine 19(28-29):4053-4060.
• Scheerlinck J.-P. Y. (2001). Genetic adjuvants for DNA vaccines. Vaccine 19(17-19):2647-2656.
• Smooker P. M., N. J. Kennedy, K. R. Steeper, H. Christopoulos and T. W. Spithill (2001). Fasciola: Kinetics and quality of humoral responses to fatty acid binding protein and cathepsin L following delivery as DNA vaccines in mice. Exp. Parasitol. 97:154-160.