Molecular tools like RNA-activated RNases could be a potential new paradigm for therapeutics.
A recent study published in the journal Nature Biotechnology has found that a new treatment appears to halt the replication of COVID-19 and flu viruses and could be delivered using a nebulizer, making it simple for use at home. The research was conducted by investigators at the Georgia Institute of Technology and Emory University.
"One of the first things that society and the CDC is going to get when a pandemic emerges is the genetic sequence. It's one of the first tools that the CDC and the surveillance teams are going to use to identify what kind of virus this is and to begin tracking it," Daryll Vanover, an author on the study said. "Once the CDC publishes those sequences -- that's all we need. We can immediately screen across the regions that we're interested in to target it and knock down the virus."
The team behind the study collaborated with the US Centers for Disease Control (CDC) and employed CRISPR technology which targets and edits specific portions of genetic code to specifically target RNA molecules.
For this study, the investigators used mRNA technology and coded for a specific protein called Cas13a which destroys parts of genetic code that allows a virus to replicate within lung cells. They used a guide strand to tell the protein where to attach on the viral RNA sequence and begin to destroy it.
Findings from the study showed that the Cas13a protein could work directly in the lung tissue and was effective in stopping the replication of SARS-CoV-2. It was also discovered that the approach could potentially work against 99% of flu strains that have been in circulation for a decade.
"In flu, we're attacking the polymerase genes. Those are the enzymes that allow the virus to make more RNA and to replicate," Philip J. Santangelo, a corresponding author on the study said. “We went after those, because they're far better conserved. We let the biology dictate what our targets would be."
The findings suggest that the novel approach could be adaptable as new viral strains emerge due to its flexibility. This could result in candidates for trials in just a short few weeks.
"This project really gave us the opportunity to push our limits in the lab in terms of techniques, in terms of new strategy," Chiara Zurla, the team's project manager and a co-author on the paper said. "Especially with the pandemic, we feel an obligation to do as much as we can as well as we can. This first paper is a great example, but many will follow; we've done a lot of work, and we have a lot of promising results."