A team of researchers has devised a way to rapidly test different nanoparticles to see where they go in the body, helping identify particles for gene delivery or RNA interference.

Many scientists are pursuing ways to treat disease by delivering DNA or RNA that can turn a gene on or off. However, a major obstacle to progress in this field has been finding ways to safely deliver that genetic material to the correct cells.

Encapsulating strands of RNA or DNA in tiny particles is one promising approach. To help speed up the development of such drug-delivery vehicles, a team of researchers from MIT, Georgia Tech, and the University of Florida has now devised a way to rapidly test different nanoparticles to see where they go in the body.

“Drug delivery is a really substantial hurdle that needs to be overcome,” says James Dahlman, a former MIT graduate student who is now an assistant professor at Georgia Tech and the study’s lead author. “Regardless of their biological mechanisms of action, all genetic therapies need safe and specific drug delivery to the tissue you want to target.”

This approach, described in the Proceedings of the National Academy of Sciences , could help scientists target genetic therapies to precise locations in the body.

“It could be used to identify a nanoparticle that goes to a certain place, and with that information we could then develop the nanoparticle with a specific payload in mind,” says Daniel Anderson, an associate professor in MIT’s Department of Chemical Engineering and a member of MIT’s Koch Institute for Integrative Cancer Research and Institute for Medical Engineering and Science (IMES).

The paper’s senior authors are Anderson; Robert Langer, the David H. Koch Institute Professor at MIT and a member of the Koch Institute; and Eric Wang, a professor at the University of Florida. Other authors are graduate student Kevin Kauffman, recent MIT graduates Yiping Xing and Chloe Dlott, MIT undergraduate Taylor Shaw, and Koch Institute technical assistant Faryal Mir.

Targeting disease

Finding a reliable way to deliver DNA to target cells could help scientists realize the potential of gene therapy — a method of treating diseases such as cystic fibrosis or hemophilia by delivering new genes that replace missing or defective versions. Another promising approach for new therapies is RNA interference, which can be used to turn off overactive genes by blocking them with short strands of RNA known as siRNA.

Delivering these types of genetic material into body cells has proven difficult, however, because the body has evolved many defense mechanisms against foreign genetic material such as viruses.

To help evade these defenses, Anderson’s lab has developed nanoparticles, including many made from fatty molecules called lipids, that protect genetic material and carry it to a particular destination. Many of these particles tend to accumulate in the liver, in part because the liver is responsible for filtering blood, but it has been more difficult to find particles that target other organs…..more here