Back in March I discussed a new therapy that combines nanotechnology and RNA interference (RNAi) to treat metastatic melanoma, and how basic and applied animal research has contributed to its’ development. Now researchers at the Georgia Institute of Technology and Emory University have reported the development of another nanotechnology and RNAi approach to treating inflammatory bowel disease (IBD), and the report published in Georgia Tech Research News highlights the importance of research in a mouse model of ulcerative colitis to the development and evaluation of their novel nanoparticle drug.
Nanoparticles remain intact in healthy tissue (upper panel). In inflamed tissue reactive oxygen species break down the nanoparticle shell to release siRNA and lower TNF-alpha levels through RNAi (lower panel). Image courtesy of Scott Wilson.
IBD is a term that covers a range of conditions where a dysfunctional immune system causes inflammation in the intestine, and includes disorders such as Crohn’s disease and ulcerative colitis which can be very debilitating to sufferers, and ultimately very damaging to their health. While treatments are available they do not work well in all cases, and often have serious side effects, so new treatments that target the inflamed tissue while sparing healthy tissues are highly desirable.
The way this new nanoparticle developed by Georgia Tech and Emory targets inflamed tissue differs from that used by scientists at Caltech to target melanoma cells. The latter employs nanoparticles coated with a protein called transferrin that is preferentially absorbed by cancer cells, while the former relies on reactive oxygen molecules produced by the inflamed tissue to break down the thioketal polymer shell of the nanoparticles, releasing the siRNA payload that triggers RNAi.
What the two approaches share is that they demonstrate the vital role played by animal research in advancing the use of nanotechnology in 21st century medicine.