Bioengineering Blood Vessels
Using a system that closely resembles the fetal environment, scientists have produced new blood vessels from cells taken from the arteries of an adult pig. When re-implanted into the same animals, the "artificial" vessels performed very similarly to normal blood vessels.
The scientists used a bioreactor to produce the vessels by simulating the fetal environment. It provided nutrients that the cells need to develop into strong vessels and "stressed" the vessels much like the heart would in normal vessel development.
Scientists used a tube of a biodegradable polymer, approximately 98% air, to provide the edifice for the vessels. Smooth muscle cells were then extracted from the pigs and layered on the outside of the tube. The layered tube was then placed in the bioreactor through which it received nutrients.
After approximately two and a half months in the bioreactor, the muscle cells were pervasive throughout the original structure. Much of the polymer had already dissolved.
Endothelial cells were then extracted from the pigs and layered on the inside of the tube. After a few days, the arteries were complete. They were then implanted back into the pigs.
The researchers noted that most culture methods currently in use are static. This study added the component of stressing or "pulsing" the vessels as the heart would in normal fetal development. When compared to vessels produced in the normal static culture method, the researchers found that the pulsed vessels were inherently stronger and were a very close approximation of the real thing.
While trials in humans are a ways off, the researchers believe that success in pigs is a big step toward being able to reproduce the results in humans. Though human vessel cells are more difficult to grow outside of the body, researchers believe they will soon be able to overcome the technological hurdles in humans.
Bioengineered vessels could help many patients suffering from heart disease. For those needing bypass surgeries, bioengineered vessels could be a potential lifesaver, particularly when the patient's own vessels have deteriorated significantly.
What do you think? Will we ultimately be successful in bioengineering human vessels? What are the potential implications? Come over to the Biology Forum and share your thoughts, opinions, and feelings.
For related information see:
Functional Arteries Grown from Cells Using Novel System that Simulates Fetal Environment
Original news release from Duke University.
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