(See also Overview of Transplantation.)
Pancreatic islet cell transplantation may be an option for people who have diabetes and whose pancreas cannot make enough insulin. The cells in the pancreas that produce insulin are called islet cells.
Transplanting islet cells is simpler and safer than pancreas transplantation, and about 75% of people who receive an islet cell transplant no longer need insulin 1 year later and may not need it for many more years. However, the long-term success of islet cell transplantation is not yet proved.
Islet cells may be separated from the pancreas of a deceased donor. The islet cells are then transplanted by injecting them into a vein that goes to the liver. The islet cells lodge in the small blood vessels of the liver, where they can live and produce insulin. Sometimes two or three infusions are done, requiring two or three deceased donors. Drugs to inhibit the immune system (immunosuppressants), including corticosteroids, are needed to help reduce the risk of rejection
Some people must have their pancreas removed because of disorders such as chronic pancreatitis. Such people will then become diabetic even if they were not diabetic previously. After the pancreas is removed, doctors can sometimes harvest the islet cells from the person’s own pancreas. These islet cells can then be transplanted back into the person’s body (autologous transplantation). Because the cells are the person’s own, immunosuppressants are not needed.
Rejection may occur. Doctors detect it by measuring levels of sugar (glucose) and a protein called hemoglobin A1C in the blood (as for diabetes).
Other complications result from the procedure. They include bleeding and blood clots in the vein that brings blood to the liver (portal vein).