October 1, 2005 Some diabetes patients who cannot live without insulin injections now have a new option: a transplant of islet cells, which produce insulin in the body. Drawing upon advances in cell biology and endocrinology, surgeons go through a 14-hour process to isolate and purify the islet cells from a donated pancreas. While there's no guarantee the success will last, it may prevent some life-threatening situations.
CHARLOTTE, N.C.--Diabetic patients who couldn't live without insulin injections are now enjoying insulin independence thanks to a new type of transplant.
Annie Anderson has a refreshing outlook on life, but that wasn't the case a few months ago. Anderson, an islet cell transplant patient says, "Totally unaware of where I was ... didn't know what had happened ... very confused -- I couldn't speak. My mind was working, but I couldn't get words out." Anderson is describing the scene that unfolded when her diabetes caused her to slip into unconsciousness. Episodes like that are no longer a threat for her. Becasue her type 1 diabetes was corrected through an experimental cell transplant.
Dr. Paul Gores, director of pancreas and islet transplantation at Carolinas Medical Center in Charlotte, N.C., says, "An islet cell transplant is a means of reversing diabetes in a patient who has lost their beta cells, which are the important cells within the little clusters of cells we call islets, which reside inside the pancreas, which produce insulin."
Transplant surgeons go through a painstaking 14-hour process to isolate and purify the islet cells from a donated pancreas. Those cells will produce insulin. Patients who go through the procedure must take immune-suppressing drugs for life with no guarantee the success will last. Dr. Gores says, "Of course, we don't know that at six, seven, eight, nine years maybe the insulin production they have right now might just totally go away and they might get totally back to square one."
For Anderson, there is no question the transplant was the right choice. She says, "It's totally changed my life, and I am so fortunate and grateful."
The longest study shows about 80 percent of patients still produce some insulin five years after their islet cell transplant, but not enough to continue to go without insulin injections. Only about 2 percent of type 1 diabetics are considered candidates for islet cell transplantation at this point, but doctors hope that number will increase.
BACKGROUND: A new experimental transplant procedure has been shown to successfully treat Type I diabetes in at least one patient, relieving that patient of the need to take daily insulin injections.
THE PROBLEM: Type I diabetes is a condition in which the pancreas does not produce enough insulin. Diabetes sufferers must inject insulin every day, or their blood sugar levels can rise out of control. Insulin is a chemical substance in the body (technically a hormone) that is needed to regular blood sugar levels. It also helps the body use fat and protein.
THE SOLUTION: Islets are cell clusters in the pancreas that control the release of insulin as needed to maintain normal levels of blood sugar in the body. Before the transplant, islet cells are collected from a donor pancreas. A catheter is inserted into the patient's abdomen and threaded into the portal vein, which carries blood to the liver. Then a teaspoonful of islet cells is injected through the catheter. The patient is conscious but anesthetized during the procedure, and can usually return home within a day or two. More than one transfusion of islet cells may be needed, and the patient must remain on immune-suppressant therapy for life to prevent the transplanted tissue from being rejected by the body. Immunosuppressive drugs can have severe potential side effects, so the procedure is not appropriate for the vast majority of diabetic patients.
WHERE TO FIND IT: Only a few medical centers in the world currently offer this procedure, which is experimental and performed as clinical research. Ten of those centers are located in the U.S., and include Carolinas Medical Center. See www.carolinas.org.
ABOUT TYPE I DIABETES: This is known as an autoimmune disease, because the body destroys its own cells: those that produce insulin. When all those cells have been destroyed, the symptoms of Type I diabetes appear. These include unexplained weight loss; vision problems; more frequent urination; and feeling very hungry, thirsty or tired. Among other long-term complications, Type I diabetes means there is an increased risk of kidney failure, nerve damage, heart disease and blindness.
Editor's Note: This article is not intended to provide medical advice, diagnosis or treatment.