Philadelphia, Pa. Heart disease patients may someday receive a dose of gene therapy that would protect injured coronary arteries from further damage and possibly even treat the underlying heart disease. The genes would be delivered to artery walls by stents, the tiny metal scaffolds that are now implanted in diseased arteries to hold the vessels open for improved blood flow.
In cell cultures and in pigs, a team led by a researcher from The Childrens Hospital of Philadelphia showed that genes in DNA added to the stents were transferred into cells on the artery wall. The study appeared in the November issue of the journal Nature Biotechnology.
"This is the first example of gene transfer in an animal model using stents for DNA delivery," said Robert J. Levy, M.D., director of the Pediatric Cardiology Research Laboratory at The Childrens Hospital of Philadelphia. "The technique has major implications for treating coronary artery disease with gene therapy."
Stents are commonly used in angioplasty procedures for partially blocked coronary arteries. After a small balloon is inserted through a catheter and inflated to widen a narrowed artery (the angioplasty procedure), an expandable wire scaffolding (the stent) is left in the artery to keep it open. However, in approximately 30 percent of patients, stents injure the artery, causing cells to grow back within a few months, often forming new obstructions.
The gene delivery technique employed by Dr. Levys team would release a gene or combination of genes that can help control blood vessel damage by inhibiting cell growth in the artery walls. "Further research is needed to identify genes that would have the most beneficial effect," said Dr. Levy, "but this study in animals shows that the gene delivery technique is possible."
Delivery is a crucial problem in any gene therapy approach. Unlike other approaches that uses viruses as delivery vehicles to carry genes into the body, Dr. Levys group uses DNA w
Contact: Maria Stearns
Children's Hospital of Philadelphia