Adult stem cells extracted from liposuctioned fat have been
used to grow new blood vessels, according to US scientists. The researchers hope that one day their technique could be used in vascular surgery.
Blocked arteries are treated using small-diameter blood vessel grafts or replacements, diverting blood around the blockage and restoring the artery's function. Currently vessels are transplanted from elsewhere in the body or synthetic materials are used.
But as Dr Matthias Nollert, associate professor at the University of Oklahoma and lead author of the study, said: 'Current small-diameter vessel grafts carry an inherent risk of clotting, being rejected or otherwise failing to function normally'.
The new technology uses adult stem cells found in extracted fat tissue, which are converted into smooth muscle cells in the laboratory. Researchers then grow these cells on a thin membrane, derived from tissue from a human placenta. These cells multiply and are then rolled into tubes of similar diameter to small blood vessels. After three to four weeks, the cells grow into usable vessels.
The researchers tested these in the lab. 'Our engineered blood vessels have good mechanical properties and we believe they will contract normally when exposed to hormones', said Dr Nollert. 'They also appear to prevent the accumulation of blood platelets, a component in blood that causes arteries to narrow'.
The research, presented at an American Heart Association conference, is still at a preliminary stage but the team hopes to test the blood vessels in animals in the next six months.