Doctors have found a way around a major obstacle in the effort to perfect transplants of islet cells. Only one pancreas needed for transplant of islet cells, rather then two or three. Such transplants usually succeed only if islet cells from the pancreases of two or even three donors are used – a significant drawback, given the scarcity of donor organs. But now, in a trial of eight patients at the University of Minnesota, in Minneapolis, doctors have managed successful transplants of islet cells, which are needed to produce insulin, with the pancreases of single donors.
The use of anti-inflammatory drugs that are normally used to treat arthritis seems to have enabled many more of the transplanted cells to survive, said Dr. Bernhard J. Hering, director of the islet transplant program at the University of Minnesota. Patients were given these drugs before surgery to dampen the inflammation that otherwise destroys as many as half of transplanted islet cells in the first 24 hours, Dr. Hering said.
The doctors also cultured the donated islet cells in the laboratory for two days, rather than transplanting them within hours of isolating them from the donor pancreas. This step appears to give the islet cells greater resilience, Dr. Hering said.
"This is really a long-awaited development, if it can be reproduced, because it means that the efficiency of islet cells is being increased," said Dr. R. Paul Robertson, scientific director of the Pacific Northwest Research Institute, a diabetes research center in Seattle.
Diabetes researchers hope islet-cell transplants, which can be done almost as easily as a blood transfusion, in less than an hour, will one day free many people with Type 1 diabetes from the need to inject themselves with insulin several times a day to control their blood sugar.
But refining the procedure has not been easy. Among the first patients to have successful transplants five years ago, most are using insulin again-though not as much as they needed before their transplants.
Although it is possible to transplant the entire pancreas, the risk of death is great enough that the operation is rarely done in people who do not also need a kidney transplant because of diabetes-related kidney failure. Islet-cell transplants are less invasive and less dangerous.
Islet cells, which make up about 2 percent of the pancreas, can be isolated from cadaver pancreases and then transplanted through a catheter into the recipient’s liver. They cannot be placed into the pancreas, because that organ is too vulnerable to inflammation.
Since the addition of immunity-suppressing drugs to prevent rejection of the new cells, the Edmonton protocol, with some variations, has been used on about 500 patients worldwide, "We’ve come a long way in a really short time, and I think islet transplantation is here to stay," Dr. Shapiro said. "It’s still far from perfect, however."
A total of 73 patients have now received islet-cell transplants in Edmonton, most of whom have had the procedure twice. One year after transplant, 82 percent of patients need no insulin injections. After three years, however, that number falls to about 50 percent, Dr. Shapiro said. But after five years, he said, it appears that only 15 percent will still be independent of insulin.
"It appears that some of the grafts are failing, but it is not a complete failure," Dr. Shapiro said. "Some of the transplanted cells are still producing insulin."
Last month, working with surgeons in Kyoto, Japan, Dr. Shapiro accomplished the first islet-cell transplant from a living donor. A 27-year-old woman with Type 1 diabetes was given islet cells that had been isolated from half of her mother’s pancreas.
Such transplants would expand the supply of donor cells. But some experts are wary of risks to donors.
The Journal of the American Medical Association Feb 15, 2005
Advancing Understanding of Type 2 Diabetes
Learn more about incretin hormones and their important gluco-regulatory effects.
Do you have patients with painful, numb feet? Over 2500 Anodyne Neuropathy Care Centers(r) are reducing pain and improving sensation and balance for thousands of patients per month. To find out how you can help your patients get back to life, click here.
Pharmacists learn how you can help patients with hyperlipidemia we now have 2, 1 hour ACPE approved credits for you. Please visit Defining the Role of the Pharmacist in Cholesterol Monitoring http://ce.rxschool.com/cholesterol_monitoring.cfm and The Role of Cholesterol and Hyperlipidemia in the Pathophysiology of Cardiovascular Disease