A new study shows for the first time that lab-created heart valves implanted in young lambs for a year were capable of growth within the recipient. The valves also showed reduced calcification and improved blood flow function compared to animal-derived valves currently used when tested in the same growing lambmodel.
If confirmed in humans, these new heart valves could prevent the need for repeated valve replacement surgeries in thousands of children born each year with congenital heart defects. The valves can also be stored for at least six months, which means they could provide surgeons with an “off the shelf” option for treatment.
The researchers used a hybrid of tissue engineering and regenerative medicine to create the growing heart valves. Over an eight-week period, they used a specialized tissue engineering technique they previously developed to generate vessel-like tubes in the lab from a post-natal donor’s skin cells. To develop the tubes, researchers combined the donor sheep skin cells in a gelatin-like material, called fibrin, in the form of a tube and then provided nutrients necessary for cell growth using a bioreactor.