A Single-dose DNA vaccine platform to safely induce protective immunity against Zika

Our team has already developed a fast, low cost and effective DNA vaccine that stimulates potent immune responses for COVID-19 and its variants in mice. This has entered human trials aiming to demonstrate safe and effective vaccination and immune booster deployment. This approach can also be used to develop a safe and effective vaccine to prevent infection by flaviviruses such Dengue and Zika. Like other Zika vaccines being developed, ours will help the body to make antibodies to stop the Zika virus entering cells and causing the person to become infected. What makes this vaccine different from other approaches is that it will also stimulate the immune system to make special T cells that can recognise and kill cells that may have been infected with the virus. These T cells will also remain in the body longer than antibodies and be there in case of future infections. The proposed Zika vaccine will be generated as several variants targeting either a non-structural protein made by the virus, or a defective intact virus using DNA as the template. Most DNA vaccines under trial are administered using mild electric shock (electroporation) or pressure to increase efficacy of the DNA delivered. Although this approach works it requires an expensive device to deliver the vaccine. This is not practical when millions of healthy subjects will need to be immunised, as during the COVID-19 pandemic, or in potential future pandemics of flaviviruses like Zika. To overcome this problem, we have developed an elegant system to allow the DNA to be given by simple injection. This technology is called GET and we have modified this system to enhance the activity of vaccination for COVID-19 using polymer chemistry. Our aim is to test the new Zika vaccines we engineer by vaccinating mice and at the end of the project be positioned to allow us and our Brazilian collaborators to start human trials quickly and validate our novel DNA approach in Brazil, a country significantly affected by Zika. This strategy could have a transformative impact on pandemic prevention in the developing world and globally. Importantly this will allow a new class of DNA vaccines to be employed for many other diseases allowing us to be better prepared for the next pandemic.