According to the March of Dimes, heart defects are among the most common birth defects and are the leading cause of birth-related deaths. In the United States alone, about 35,000 infants (1 out of every 125) are born each year with heart defects. Among the most common congenital heart problems are heart valve defects, where the heart valve either does not close normally or is narrowed or blocked, so blood can’t flow smoothly.
Now, German scientists are hopeful that within five to seven years, they will be able to fashion a new heart valve for children born with heart valve defects that would grow as the child develops using stem cells collected at birth from the child’s own umbilical cord blood.
In a recent concept study, cardiologists at the University Hospital of Munich collected umbilical cord blood at birth and then froze it to preserve the cells. After 12 weeks, they harvested the stem cells, seeded them onto eight biodegradable heart valve scaffolds and grew them in the laboratory. Upon examination with electron microscopes, researchers could see the cells had grown into the pores of the scaffolding and formed a tissue layer. Biochemical examination indicated that the cells had produced important elements of the “extracellular matrix,” the portion of body tissue that functions outside of cells and is essential to tissue function and structure.
Over time, the scaffolds will dissolve, leaving behind a fully formed structure made from the cells, explained cardiac surgeon Ralf Sodian, who led the study. “The basic idea is to implant something living, functional from your own cells which will integrate into the surrounding tissue with the potential to grow. Tissue engineering provides the prospect of an ideal heart valve substitute that lasts throughout the patient’s lifetime and has the potential to grow with the recipient and to change shape as needed.”
Sodian cautioned that, while the technique shows promise, researchers need to work out several issues before they can attempt it in people. The next step is test the procedure by implanting these tissue-engineered heart valves into young lambs and watching to see how they grow and function over time. Sodian says he hopes to begin these experiments next year.
Adapted from the Health News.
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