UPDATES IN PANCREATIC ISLET CELL TRANSPLANTATION
Thelma D. Crisostomo, M.D., FPCP, FPSEM
Makati Medical Center

This topic was discussed in the American Diabetes Association Scientific Session last June 24, 2001.

An islet transplant team from Edmonton Alberta reported their work on 15 Diabetic Type 1 patients who have undergone Pancreatic Islet Cell transplantation that occurred in the last 3 years.

They announced that 10 of these patients are completely insulin free for at least 1 ½ to 3 years and that the remaining 5 of these require only about 20% of their previously insulin dosages.

The teams have expressed their difficulties in isolating high quality islet cells from cadaver donors. These islet cells are insulin-producing cells from the Pancreas. They get those pancreas from Brain-dead individuals and processing of these pancreas must occur within 8 hours to be able to acquire islet cells that are still functioning, these pancreas go through a tedious 8 hour processing period in a high tech sophisticated laboratory. The result of these processes gives a recovery of only 20% of the total Islet cell population, about 40cc of pure pancreatic islet isolate. These isolated cells are tested under the microscope to observe their function if they are of high quality, meaning if these cells are really producing insulin or are they dead cells. Only high quality islets are infused into the portal vein (near the liver) of these Type 1 patients to achieve better success rates.

Several researches are still trying to improve the technique of islet cell isolation to improve recovery rate of islet cells that was mentioned to be only 20%. These infusions of 20% recovered Islet on Type 1 patients makes them insulin free in normal circumstances but their insulin reserves are low unlike the normal non-diabetic patient. In period of stress, there is possibility that they may still require insulin.

Several groups of researchers are also looking into other sources of islet cells. They are looking into pancreas from living donors to eliminate the waiting time period prior to processing which will improve harvest of quality islet cells. There are however, ethical issues involve with this procedure.

Other groups of scientists are also trying to produce islet cells from embryonic stem cells. These are very young cells that have not developed a particular function yet. They are engineered in the laboratory to develop into islet cells. So far, they met some success in having these primary cells produce some insulin but it has not yet been perfected yet.

Other groups are working in the area of immunosuppression to prevent graft injection and development of insulin resistance. Newer drugs are being tried that will persevere the function of the transplanted Islet cells in the Type 1 patient.

Many researchers from Canada, USA, Europe and Asia are joining hands and communicating with each other trying to improve and perfect Islet cell Isolation, transplantation techniques, immunosuppression methods and finding novel sources of islet cells. In the near future many Type 1 diabetics may soon find themselves insulin free at last and will be living better and fuller lives.