You are hereDecember 31, 2012
Stem cells prodded into two tissue types essential for growing blood vessels
The work is important because networks of new blood vessels, assembled in the lab for transplanting into patients, could be a boon to those whose circulatory systems have been damaged by heart disease, diabetes and other illnesses.
“That’s our long-term goal—to give doctors a new tool to treat patients who have problems in the pipelines that carry blood through their bodies,” said Sharon Gerecht, an assistant professor of chemical and biomolecular engineering who led the research team. “Finding out how to steer these stem cells into becoming critical building blocks to make these blood vessel networks is an important step.”
The study, published in the January issue of Cardiovascular Research, details how the team focused on vascular smooth muscle cells found within the walls of blood vessels. Two types have been identified: synthetic smooth muscle cells, which migrate through the surrounding tissue, continue to divide and help support the newly formed blood vessels; and contractile smooth muscles cells, which remain in place, stabilize the growth of new blood vessels and help them maintain proper blood pressure.
In an earlier study supervised by Gerecht, her team was able to coax stem cells to become a type of tissue that resembled smooth muscle cells but didn’t quite behave properly. In the new experiments, the researchers tried adding various concentrations of growth factor and serum to the previous cells.
“When we added more of the growth factor and serum, the stem cells turned into synthetic smooth muscle cells,” Gerecht said. “When we provided a much smaller amount of these materials, they became contractile smooth muscles cells.”
This ability to control the type of smooth muscle cells formed in the lab could be critical in developing new blood vessel networks, she said. “When we’re building a pipeline to carry blood, you need the contractile cells to provide structure and stability,” she added. “But in working with very small blood vessels, the migrating synthetic cells can be more useful.”
The current work could also help researchers understand how blood vessels are stabilized in tumors, which could be useful in the treatment of cancer.
“We still have a lot more research to do before we can build complete new blood vessel networks in the lab,” Gerecht said.