The future of vaccines may be more like eating a salad than getting the vaccine. Scientists at UC Riverside are studying whether they can turn edible plants like lettuce into mRNA vaccine factories.
Messenger RNA or mRNA technology, used in COVID-19 vaccines, works by teaching our cells to recognize us and protect us from infectious diseases.
One of the challenges of this new technology is that it must be kept cold to maintain stability during transport and storage. If this new project is successful, herbal mRNA vaccines – which can be consumed – could overcome this challenge with the ability to be stored at room temperature.
The objectives of the project, made possible by a grant of $ 500,000 from the National Science Foundation, are threefold: to show that DNA containing mRNA vaccines can be successfully administered in the part of plant cells where it will replicate, demonstrate that plants can produce enough mRNA to compete with a traditional shot, and finally, determine the right dosage.
“Ideally, a single plant would produce enough mRNA to vaccinate a single person,” said Juan Pablo Giraldo, associate professor in the department of botany and plant sciences at UC Riverside who is leading the research, conducted in collaboration with scientists. from UC San Diego and Carnegie Mellon University.
“We are testing this approach with spinach and lettuce and have long term goals of people growing it in their own gardens,” Giraldo said. “Farmers could also cultivate entire fields. “
Chloroplasts, small organs in plant cells that convert sunlight into energy that the plant can use, are essential in doing this job. “These are tiny solar-powered factories that produce sugar and other molecules that allow the plant to thrive,” Giraldo said. “They are also an untapped source for making desirable molecules.”
In the past, Giraldo has shown that it is possible for chloroplasts to express genes that are not naturally part of the plant. He and his colleagues did this by sending foreign genetic material into plant cells inside a protective envelope. Determining the optimal properties of these casings for delivery into plant cells is a specialty of Giraldo’s laboratory.
For this project, Giraldo has teamed up with Nicole Steinmetz, professor of nanotechnology at UC San Diego, to use nanotechnologies designed by her team that will provide genetic material to chloroplasts.
“Our idea is to reuse naturally occurring nanoparticles, namely plant viruses, for the delivery of genes to plants,” said Steinmetz. “A little bit of engineering goes into it to get the nanoparticles to go to the chloroplasts and also to make them non-infectious to plants.”
For Giraldo, the possibility of developing this idea with mRNA is the culmination of a dream. “One of the reasons I started working in nanotechnology was that I could apply it to plants and create new technological solutions. Not just for food, but also for high-value products like pharmaceuticals, ”Giraldo said.
Giraldo is also co-leading a related project using nanomaterials to deliver nitrogen, a fertilizer, directly to chloroplasts, where plants need it most.
Nitrogen is limited in the environment, but plants need it to grow. Most farmers apply nitrogen to the soil. As a result, about half of it ends up in groundwater, contaminating waterways, causing algae blooms and interacting with other organisms. It also produces nitrous oxide, another pollutant.
This alternative approach would introduce nitrogen into chloroplasts through the leaves and control its release, a much more efficient application method that could help farmers and improve the environment.
The National Science Foundation granted Giraldo and his colleagues $ 1.6 million to develop this targeted nitrogen delivery technology.
“I am very excited about all of this research,” Giraldo said. “I think it could have a huge impact on people’s lives. “