In work that could lead to safe and effective techniques for gene therapy, MIT researchers have found a way to fine-tune the ability of biodegradable polymers to deliver genes.
Gene therapy, which involves inserting new genes into patients' cells to fight diseases like cancer, holds great promise but has yet to realize its full potential, in part because of safety concerns over the conventional technique of using viruses to carry the genes.
The new MIT work, published this week in Advanced Materials, focuses on creating gene carriers from synthetic, non-viral materials. The team is led by Daniel Anderson, research associate in MIT's Center for Cancer Research.
“What we wanted to do is start with something that's very safe-a biocompatible, degradable polymer-and try to make it more effective, instead of starting with a virus and trying to make it safer,” said Jordan Green, a graduate student in biological engineering and co-first author of the paper.
Gregory Zugates, a former graduate student in chemical engineering now at WMR Biomedical, Inc., is also a co-first author of the paper.
Gene therapy has been a field of intense research for nearly 20 years. More than 1,000 gene-therapy clinical trials have been conducted, but to date there are no FDA-approved gene therapies. Most trials use viruses as carriers, or vectors, to deliver genes.
However, there are risks associated with using viruses. As a result, many researchers have been working on developing non-viral methods to deliver therapeutic genes.
The MIT scientists focused on three poly(beta-amino esters), or chains of alternating amine and diacrylate groups, which had shown potential as gene carriers. They hoped to make the polymers even more efficient by modifying the very ends of the chains.
When mixed together, these polymers can spontaneously assemble with DNA to form nanoparticles. The polymer-DNA nanoparticle can act in some ways like an artificial virus and deliver functional DNA when injected into or near the targeted tissue.