Stem cells researchers from the University of Maryland School of Medicine in Baltimore have designed a treatment that takes a child’s skin cells, reprograms them to function as heart valvular cells and then utilizes these cells to engineer a pulmonary valve that can grow with the patient.
“Current valve replacements cannot grow with patients as they age, but the use of a patient-specific pulmonary valve would introduce a ‘living’ valvular construct that should grow with the patient. Our study is particularly important for pediatric patients who often require repeated operations for pulmonary valve replacements,” said lead author David L. Simpson, Ph.D., The study is published in the current issue of Annals of Thoracic Surgery.
In the heart, the “pulmonary valve” is located between the right ventricle and the pulmonary artery, which takes blood from the right side of the heart to the lungs. This crescent-shaped valve aids in moving blood from the heart into the lungs.
According to data from the Society of Thoracic Surgeons (STS) Congenital Heart Surgery Database, close to 800 patients experience pulmonary valve failure and could benefit from bioengineered patient-specific pulmonary valves. The STS Database collects information from more than 95% of hospitals in the United States and Canada that perform pediatric and congenital heart surgery. Numbers compiled from these hospitals show that approximately 3,200 patients underwent pulmonary valve replacement during a four-year period from January 2010 to December 2013.
Although the study was conducted outside the body, the next step will be implanting the new valves into patients to test their durability and longevity.
“We created a pulmonary valve that is unique to the individual patient and contains living cells from that patient. That valve is less likely to be destroyed by the patient’s immune system, thus improving the outcome and hopefully increasing the quality of life for our patient,” said senior co-author Sunjay Kaushal, M.D., Ph.D.. “In the future, it may be possible to generate this pulmonary valve by using a blood sample instead of a skin biopsy.”
David Simpson added that he hopes the study will encourage additional research in tissue engineering and entice more people to enter the field, “Hopefully, growing interest and research in this field will translate more quickly into clinical application.”