Scientists from Osaka University in Japan has successfully completed the world's first transplant of lab-grown heart muscle tissues.
The first-of-its-kind surgery was carried out on a patient in Osaka earlier this month, the researchers announced at a news conference on Monday, according to Japanese news agency Jiji Press.
While it’s still relatively early days for the treatment, it’s hoped it could be an accessible alternative to full heart transplants in the not too distant future.
The clinical trial used induced pluripotent stem cells (iPS) – a kind of “master cell” that can turn into any cell type – derived from healthy donors’ blood cells. The iPS were then used in the large scale production of cardiomyocytes, cells that make up the heart muscle and help it contract. Millions of iPS-derived cardiomyocytes were applied onto a degradable sheet, just 0.1 millimeters thick, that was then transplanted onto the patient’s damaged heart tissue.
The patient suffered from severe ischemic cardiomyopathy, a condition where the heart muscle is weakened as a result of a heart attack or coronary artery disease. After the new cardiomyocyte sheet is transplanted onto the damaged heart, the cells will continue to grow and help to regenerate blood vessels, eventually allowing the heart to beat like its old self, while the sheet itself degrades.
The clinical trial sought to test the safety and effectiveness of this radical treatment. Over the next three years, the team hopes to carry out further lab-grown heart muscle tissue transplants on nine other patients with ischemic cardiomyopathy. All being well, the treatment could be an accessible alternative to heart transplants.
Between 4,000 to 4,500 heart transplants are carried out every year across the world, around half of which are in the US. Although they can be remarkably effective, they come with many caveats and pitfalls. For one, they are extremely expensive. Patients in the US can expect to be billed around $1,382,400 for a heart transplant. Equally, a transplant requires a compatible available donor heart, which means patients are often left on a lengthy waiting list. It’s estimated that around one in six people do not receive the heart transplant they require, according to the British Heart Foundation.
In theory, lab-grown heart muscle tissue would eradicate these problems. Professor Stephen Westaby, a leading British heart surgeon at John Radcliffe Hospital in Oxford said in 2017 that heart transplants will become obsolete within the next decade, suggesting that a combination of heart pumps and stem cells will serve as an easier and more effective alternative.
Although the new treatments will certainly introduce fresh challenges, this clinical trial has shown how revolutionary stem cell treatments hold the real potential to save thousands of lives.
“I hope that [the transplant] will become a medical technology that will save as many people as possible, as I’ve seen many lives that I couldn’t save,” Yoshiki Sawa, a professor at Osaka University’s cardiovascular surgery unit, told reporters.