Bioengineered Arteries Grown from Cells.

• Position: Succesfully creating pig arteries through bioengineering - Brief Article

Utilizing a novel system that mimics the fetal environment, Laura Niklason, an anesthesiologist and bioengineer at Duke University Medical Center, Durham, N.C., has used cells taken from adult pigs' arteries to grow blood vessels that look and act like the real thing.

When implanted back into the same animals, the engineered vessels, which were grown in a bioreactor that provided nutrients and pulsed the growing vessels much like a heart would, were as strong as native vessels, could hold a suture without ripping, and responded to drugs in much the same manner.

To create the arteries, she fashioned a tube from a thin sheet of biodegradable polymer which, like a sponge, is 97% air. Smooth muscle cells were collected from the animal arteries and were impregnated throughout the polymer tube. Once placed within the bioreactor, the tube was bathed with similar nutrients found in native vessels.

After eight to 10 weeks within the bioreactor, the smooth muscle cells proliferated and filled all the spaces within the polymer scaffolding, most of which had dissolved by that time. To complete the artery, Niklason then added endothelial cells, which line the interior of blood vessels, to the inside of the tube. Several days later, the arteries were ready for implantation back into the pigs.

To see if arteries grown in the pulsing environment worked better than those grown in a static system, Niklason implanted arteries grown both ways back into the pigs. She followed their performance for four...