Children’s Hospital of Philadelphia is reporting that its team of scientists has achieved promising results in attaching therapeutic genes to the bare metal surface of stents. From the press release:
Researchers at The Children’s Hospital of Philadelphia have developed a novel technique to attach therapeutic genes to a stent’s bare metal surface. This technique allows the genes to help heal the surrounding blood vessels, while avoiding the inflammation caused by polymer coatings.
The research team reported their proof-of-principle study, using cell culture and animal models, in the early edition of the Proceedings of the National Academy of Sciences, published online this week.
“This is the first study to demonstrate successful delivery of a gene vector from a bare metal surface,” said senior author Robert J. Levy, M.D., the William J. Rashkind Chair of Pediatric Cardiology at The Children’s Hospital of Philadelphia. A gene vector is a biological substance, in this case an adenovirus, capable of delivering a therapeutic gene to target cells.
Dr. Levy’s team created a unique water-soluble compound, polyallylamine biphosphonate, that binds to the stent’s metal alloy surface in a layer with the thickness of only a single molecule. The biphosphonate holds and gradually releases adenovirus particles of the type used to deliver therapeutic genes.
In cell cultures, the adenovirus successfully delivered genes from alloy samples to animal arterial smooth muscle cells. In a second experiment using rodents, the researchers detected gene expression with significantly lower restenosis in the carotid arteries of animals with the experimental stents, compared to control animals with conventional, polymer-coated stents.
Link to the abstract on PubMed…