In an article in Medical Xpress, Japanese doctors have performed a “first” by transplanting liver cells (made with embryonic stem cells) into a newborn. The six-day-old infant was diagnosed with urea cycle disorder. The disorder prevents the liver from clearing toxic ammonia.
The controversy involves ethical issues due to the fact that embryonic stem cells originate from fertilized eggs. While the donors of the fertilized egg consent to the process, eventually the embryos are destroyed. The ethical issues have yet to be resolved.
Waiting for Liver Transplant
A liver transplant is generally not safe until an infant weighs about thirteen pounds. Waiting months for the transplant would have been fatal for this newborn whose identity was not disclosed.
Transplant donors are scarce. Successful transplants require highly specialized doctors, medicine, and equipment.
Although liver cells are usually available in the US and Europe where they are taken from donors who are brain-dead, the Japanese supply is somewhat limited.
It is therefore difficult to avoid fatalities in Japanese children who are waiting for liver transplants.
The new stem cell treatment is not yet intended to replace transplants, but the doctors feel that this success presents a possibility for further research.
The NCCHD Bridge Treatment
The doctors at the National Center for Child Health (NCCHD) in Japan made a decision to attempt a “bridge treatment” for the infant.
The NCCHD is only one of two organizations in Japan authorized to work with fertilized eggs in the development of new treatments. Permission to work with the fertilized eggs must come from both donors after their fertility treatment is completed.
The doctors injected 190 million liver cells into blood cells in the infant’s liver. The cells were taken from embryonic stem cells (ES cells). The press release issued at a later date confirmed that the patient’s blood ammonia did not increase.
The next step was the actual liver transplant, which took place several months later. A person cannot live without a liver which performs about five hundred functions.
However, a portion of a liver may be used for a transplant because the organ can regenerate. The baby’s father donated that portion. The transplant was a success and the baby was discharged from the hospital six months after its birth.
Researchers feel that there is a very exciting possibility for a variety of interventions in the future with this approach.
