Lab-grown artificial blood vessels successfully implanted in animal model

ST. PAUL, Minn., Sept. 28 (UPI) -- A new study in artificial blood vessel bioengineering led by the University of Minnesota suggests the need for repeated surgeries for patients with heart-related diseases may soon be eliminated.

The research focused on developing new treatments for heart defects in children. During the study, scientists created artificial blood vessels designed to grow within their hosts using their existing blood cells.

UMN's study was led by biomedical engineering Professor Robert Tranquillo, who tested vessel-like tubes created using post-natal donor skin cells in young lambs. Tranquillo hailed the experiment as a groundbreaking success.

"This might be the first time we have an 'off-the-shelf' material that doctors can implant in a patient, and it can grow in the body," Tranquillo said in a press release. "In the future, this could potentially mean one surgery instead of five or more surgeries that some children with heart defects have before adulthood."

Before the devices were implanted, the cells used to create the tubes were removed using special detergents to reduce the chance of rejection. The cleaning process left behind a cell-free matrix that did not cause an immune reaction in the test subjects. Tranquillo went on to explain the experiment depended on the vessel graft's ability to grow on its own once implanted.

"What's important is that when the graft was implanted in the sheep, the cells repopulated the blood vessel tube matrix," he continued. "If the cells don't repopulate the graft, the vessel can't grow. This is the perfect marriage between tissue engineering and regenerative medicine where tissue is grown in the lab and then, after implanting the decellularized tissue, the natural processes of the recipient's body makes it a living tissue again."

Researchers observed the vessel graft's diameter increased by 56 percent after 50 weeks, which allowed for much more blood to be pumped through it.

Tranquillo says human clinical trials mark the next step of his research, which he hopes the Food and Drug Administration will approve in the next few years.