Stem-cell science is key to tissue regeneration
By GARRETT NEESE
HOUGHTON – Regeneration of human tissue can occur when adult stem cells, which are used for the cardiovascular tissue, are taken from fat tissue, bone marrow and other sources from patients or donors, explained Michigan Tech scientist Feng Zhao, whose work building nanoscaffolds out of natural materials to grow tissues was given the Rising Star Award by the Biomedical Engineering Society.
One type of cardiovascular tissue is a small-diameter blood vessel – about 6 millimeters – used for coronary artery bypasses.
“For this kind of small-diameter blood vessel, the real blood vessel has a highly organized structure,” Zhao said. “That is very important for the mechanical stress of the blood vessel. The blood vessel, you have blood flow. It has very high mechanical stress. For our scaffolding, it has aligned fibers. It can also align the cells. We can make a tissue just like that. The organization of the cells and their material are similar to the native blood vessel.”
Zhao also works on an even smaller level, building cardiac patches for damaged tissue out of capillaries. At 10 to 20 microns, they’re about 300 times narrower than the coronary artery.
“We not only have the cells aligned, the tissue aligned, we also engineer capillaries in this tissue and also get them aligned, she said. So all alignment of the tissue, capillary, cells, fibers, are important for the functional performance of the engineered tissue.”
Other potential applications for the tissue include adding cancer cells to test treatments. They may also be used to test pharmaceutical drugs.
“If we have this kind of artificial tissue, we can use them to test the drug,” Zhao said. “Now you don’t have to use an animal. They highly mimic the native tissue.”
It’s still early. They’re making tissues and testing them on small animals, which could take some time, Zhao said. If those tests are successful, the searchers would move on to larger animals, and eventually, clinical trials on humans.
“That might take quite a long time,” Zhao said. “But we are on the road.”