About 18 months ago, the nanotech trade press was buzzing with the work of Hongbin Yu and Hao Yan, both from Arizona State University (ASU), when they developed a method that used DNA origami as a scaffold. When the DNA scaffolding was combined with “nano islands” made from gold, it enabled the manufacturing of smaller electronic memory devices.
Now Yan has joined with Yung Chang, a biodesign immunologist also from ASU, to use three-dimensional DNA structures as a scaffold on which they piggybacked synthetic vaccine complexes to make the delivery of the vaccines safer and more effective.
“When Hao treated DNA not as a genetic material, but as a scaffolding material, that made me think of possible applications in immunology,” said Chang, an associate professor in the School of Life Sciences and a researcher in the Biodesign Institute’s Center for Infectious Diseases and Vaccinology in a university press release. “This provided a great opportunity to try to use these DNA scaffolds to make a synthetic vaccine.”
The research, which was published in the journal Nano Letters ("A DNA Nanostructure Platform for Directed Assembly of Synthetic Vaccines"), made its first test with the DNA scaffold by placing an immune stimulating protein called streptavidin (STV) and an immune response boosting compound called an adjuvant (CpG oligo-deoxynucletides) to different branches of the DNA structure.
After determining that cells would absorb the DNA structure with its synthetic vaccine payload, the researchers waited to see if an immune cascade response would follow. It did and was really beyond the researchers expectations.
The results showed that the mice that were given the full vaccine complex consisting of the DNA scaffold and the STV and GpG displayed an immune response nine times higher than those that had been injected solely with the STV and GpG.
"We were very pleased," said Chang in the press release. "It was so nice to see the results as we predicted. Many times in biology we don't see that."
This is really just a leaping off point, according to the researchers. They believe that this proof of concept indicates that an unlimited range of antigens could be used in this way for fighting a host of diseases.