London, Nov 12: Children with heart defects have
new hope with scientists on track to develop perfectly-matched
new heart valves using stem cells from their umbilical
cord blood.
"In our concept, if prenatal testing shows a heart
defect, you could collect blood from the umbilical cord at
birth, harvest the stem cells, and fabricate a heart valve
that is ready when the baby needs it," said Ralf Sodian, the
lead author of the study, presented at the American Heart
Associations Scientific Sessions 2008.
Tissue engineering provides the prospect of an ideal
heart valve substitute that lasts throughout the patients
lifetime and has the potential to grow with the recipient and
to change shape as needed," said Sodian, a cardiac surgeon at
the German University Hospital of Munich.
Children born with malfunctioning heart valves, which
cant be surgically repaired, rely on replacements from animal
tissue, compatible human organ donations or artificial
materials. These replacements are lifesaving, but dont grow
and change shape as a child develops; so two or more surgeries
may be needed to replace outgrown valves.
The latest tissue engineering of heart valves is still
in its infancy, with various researchers investigating the
possibility of using cells from blood, bone marrow or amniotic
fluid, the Science Daily online reported.
In the study, the research team used stem cells
(CD133+ cells) derived from umbilical cord blood. The cord
blood was frozen to preserve it. After 12 weeks, the cells
were seeded onto eight heart valve scaffolds constructed of a
biodegradable material and then grown in a laboratory.
However, several crucial questions remain to be solved
regarding tissue-engineered functional heart valves, including
identifying the optimal scaffold material and learning how to
condition the valves in the laboratory so they work properly
after being implanted, Sodian said.
Bureau Report
