Optimisation of DNA vector activity and delivery for improved vaccination

The manufacture of protein-based or live attenuated vaccines is an expensive and time-consuming process which is not suited to mass vaccination programmes against pathogens which emerge in rapid outbreaks, such as Ebola, or show high mutation rates, such as Flu. Production of DNA based vaccine vectors offers the possibility of creating new vaccines more quickly and at lower cost. To date these DNA vaccines have failed to make substantial clinical translation due to lack of biological activity. This can be improved by addressing 2 challenges. 1) Ensuring the delivery of these constructs into the skin can be achieved more effectively. 2) Using synthetic biology approaches to enhance the activity and specificity of DNA constructs.
It has previously been shown that mice can be transfected with dbDNA (doggie bone DNA), using ultrasound-mediated cavitation, whilst resulting in minimal skin damage. Furthermore, following application of this method to deliver a dbDNA vector expressing a Flu peptide, relevant levels of anti-flu antibodies could be detected in mice. Despite these observations, questions still remain on the mechanism of how cavitation contributes to transfection, which cells are transfected, the immune response that results and which parameters are optimal.
The ultrasound parameters for delivery of DNA across the skin will be refined, using luciferase reporter assays in mice transfected with luciferase dbDNA. Mice will be treated with set dosages and different parameters and the observed fluorescence will be used to define optimal delivery. The mechanism of delivery will be explored by transfecting murine skin with dbDNA and quantifying the dbDNA content of different cell types. A better understanding of the mechanism of cavitation mediated DNA vaccine delivery can contribute to DNA vector design.
In collaboration with Touchlight Genetics Ltd, an optimized dbDNA vector will be designed which elicits the immune response for immunisation and the production of which can easily be scaled up, using their proprietary technology. Predictive modelling of enhancements to the DNA vectors, systematic optimization and the design-build-test cycle will be employed to ensure the DNA vectors provide the best levels and profile of Flu peptide production. A novel method of initial screening using an immune cell line will be developed to screen candidate vectors before tests in mice. Hopefully, this technology will allow for easier and cheaper alteration of the flu vaccine.
Finally, in collaboration with Owen Mumford Ltd., a user-friendly device will be engineered based on the determined ultrasound parameters and compatible with dbDNA vector to give the most effective delivery of the optimised dbDNA vaccine delivery. This instrument will aim to be both easy to use and provide clear user-feedback on the success of the delivery, as well as enable commercial application of the technology.
Novel engineering and science content
Overall, a novel, optimised dbDNA flu vector will be developed and a customized complementary delivery device, utilizing ultrasound-mediated cavitation. To achieve this, research will be done to elucidate the mechanism underpinning this technology and an in vitro method to quantify the efficacy of dbDNA vectors developed. The goal of the project is to bring these different facets together to create a prototype device and associated dbDNA flu vector, which will function as an effective flu vaccine. This will be developed to reach a 'pre-clinical' stage.
This project falls in the EPSRC "Synthetic Biology" and "Clinical Technologies" research area. The systematic optimization of DNA vectors, and model-guided design, as advocated in "Synthetic Biology", will be used to accelerate the development of DNA vaccines. The "Clinical Technologies" research area is seen in the application, where biology and device engineering are combined to create a relevant product.

The emerging and dynamic field of Synthetic Biology has the potential to provide solutions to some of the key challenges faced by society, ranging across the healthcare, energy, food and environmental sectors. The UK government has recently a "Synthetic Biology Roadmap", which presents a vision and direction for Synthetic Biology in the UK. The report projects that the global Synthetic Biology market will grow from $1.6bn in 2011 to $10.8bn by 2016. It highlights that there is an urgent need for the UK to develop the interdisciplinary skills required to take advantage of the opportunities provided by Synthetic Biology.

The challenge to the academic and industrial research communities is to develop new translational approaches to ensure that these potential benefits are realised. These new approaches will range across the design and engineering of biologically based parts, devices and systems as well as the re-design of existing, natural biological systems across all scales from molecules to organisms. The techniques will encompass not only individual cells, but also self-assembled biomimetic systems, engineered microbial communities and multicellular organisms, combining multiple perspectives drawn from the engineering, life and physical sciences.

Realising these goals will require a new generation of skilled interdisciplinary scientists, and the training of these scientists is the primary goal of the SBCDT. Our programme will give the breadth of coverage to produce a "skilled, energized and well-funded UK-wide synthetic biology community", who will have "the opportunity to revolutionise major industries in bio-energy and bio-technology in the UK" (David Willetts, Minister for Universities and Science) in their future careers. This will be made possible through genuine inter-institutional collaboration in partnership with key industrial, academic and public facing institutions.

The potential impact of the SBCDT, and its potential national importance, are very therefore high, and the potential benefits to society are significant.