Tobacco leads to development of new Zika vaccine

Since the onset of the Zika virus in 2015, experts have been researching ways to combat its spread, but now, Arizona State University may have a plant-based vaccine ready to meet the challenge.

The effort is different than existing efforts in that it appears to be more potent, safer and even cheaper to produce. Developed by a team led by ASU Biodesign Institute’s Qiang Chen, it uses tobacco plants in its production.

“All flaviviruses have the envelope protein on the outside part of the virus,” said Chen, a viral expert who has spent the past decade working on efforts to combat West Nile and Dengue fever. “It has three domains. The domain III has a unique stretch of DNA for the Zika virus, and we exploited this to generate a robust and protective immune response that is unique for Zika.”

West Nile and Dengue fever are both flaviviruses as well, meaning they essentially come from the same family as Zika. Thus, Chen’s research led him to a key piece of the Zika viral protein–DIII–that helps its spread. In turn, his team grew the protein in tobacco plants and then tested immunization in mice. Those mice demonstrated 100 percent protection against multiple Zika strains thereafter.

“Above all, we have to ensure the utmost safety with any Zika vaccine, especially because the people who will need it most, pregnant women, have the most worries about their own health, and the health of the fetus,” Chen said. “This has to be 100 percent safe and effective.”

Bearing that in mind, Chen hopes to begin the first phase of a human clinical trial within the next two years.

There remain to date no licensed vaccines or therapeutics on the market to fight Zika, though the U.S. government currently has a $100 million clinical trial of a Zika vaccine candidate under testing.