Japan’s National Center for Child Health and Development has said it had performed the world’s first transplant of cells derived from embryonic stem, or ES, cells to a baby.
It was also the first transplant of cells derived from ES cells to a liver disease patient in the world and the first to any patient in Japan.
According to the national institute, the baby was born with a urea cycle disorder, which makes it unable to break down harmful ammonia in the liver.
In October last year, the baby was taken to the institute after developing a seizure two days after birth. On the sixth day after birth, 190 million liver cells created from ES cells were injected into the baby from blood vessels leading to the liver.
Five months later, the baby was discharged after also receiving liver tissue from his or her father.
“Although close follow-up work continues to be necessary, we believe we could safely transplant the liver cells,” said Mureo Kasahara, head of the institute’s Center for Organ Transplantation.
The national institute conducted the transplant as part of a clinical trial for approval from medical authorities. It plans to perform similar operations for four other patients, aiming to gain the approval in fiscal 2022 at the earliest.
Annually, there are believed to be around 30 to 50 urea cycle disorder patients who need such cell transplants.
Patients of the disease face the risk of brain damage or even death if they repeatedly suffer a seizure from a rise in blood ammonia levels.
A liver transplant is necessary if drugs fail to curb a rise in blood ammonia levels, but a liver transplant is difficult to carry out for patients under 3 to 5 months old.
Since the liver cell transplant, the baby has not suffered a rise in blood ammonia levels or damage to the brain. The transplanted cells are expected to have settled in the baby’s liver and started to break down ammonia.