Researchers have used adult stem cells to create functional blood vessels that can function for bypass surgeries. The work was presented at the American Heart Association's Arteriosclerosis, Thrombosis and Vascular Biology Annual Conference 2010. For many people undergoing bypass surgery, blocked arteries are replaced using another vessel from a different part of the body. But many patients don't have a suitable replacement vessel and synthetic grafts are used. However, the synthetic vessels often become clogged within a couple of years. Dr. Stephen McIlhenny and his group at Thomas Jefferson University Hospital in Philadelphia have used adult stem cells from fat tissue to create functional blood vessels. Testing the process in rabbits, they grew adult stem cells on human vein scaffolds in the lab. Grafts were prepared using adult stem cells from each test rabbit, then the graft was put back into the individual rabbits so they received grafts containing their own cells, removing the risk of transplant rejection. After eight weeks, rabbits receiving the customized grafts fared better than those receiving synthetic grafts.

Dr. McIlhenny said

"We found that using the stem cells as a coating prevented clotting and thickening of the graft wall. I would say those grafts were significantly better. Potentially, patients requiring bypass surgery could receive optimized grafts that would reduce their future complications."

McIlhenny's group has previously done work growing smooth muscle from adult stem cells for vascular grafts, and developed a method to prevent shearing of the adult stem cells from the scaffold.