University at Buffalo researchers have found a way to make stable and effective blood vessels, opening the door to the possibility of growing new vessels for such procedures as heart surgery.
In cardiac bypass surgery, blood vessels to be used around the heart are usually taken from the patient's leg. The technique can cause pain and requires additional time in the operating room.
As a result, researchers have sought to engineer blood vessels that are strong and elastic, as blood vessels need to be.
The UB researchers constructed vessels by embedding vascular smooth-muscle cells isolated from sheep umbilical cords into fibrin, the essential clotting ingredient in blood. The fibrin gel then was shaped into cylinders that several weeks later could be transplanted, according to the researchers' paper published in a recent issue of the American Journal of Physiology -- Heart and Circulatory Physiology.
The tissue-engineered blood vessels exhibited blood flow rates and responsiveness similar to those of native vessels for 15 weeks.
"These are the first tissue-engineered vessels to show long-term viability without clotting -- a key problem with small diameter vessels -- and with no adverse effects observed from the material we used," said Stelios Andreadis, associate professor of chemical and biological engineering in the UB School of Engineering and Applied Sciences.
He was a co-author on the paper with Daniel D. Swartz, research assistant professor, and James A. Russell, professor, both in the UB department of physiology and biophysics in the School of Medicine and Biomedical Sciences.
The engineered vessels may have additional applications as model systems for studying how mechanical forces and drugs act on the blood vessel wall, the researchers said.