Islet Cell Transplants: Continued Success
A Year After Islet Cell Transplants, Most Recipients Are Insulin Free
"There are no miracles in medicine, but this is a significant step forward in the treatment of diabetes. Someday we will have a cure," Owen tells WebMD.
Michael Darcy, MD, president of the society and a professor of radiology at Washington University School of Medicine in St. Louis, says that the "Edmonton protocol," as the islet cell transplants are known, represents a significant breakthrough in treatment of insulin-dependent diabetes. But Darcy, who was not involved in the Canadian study, cautions that islet cell transplantation is still experimental and should be considered only for patients who are unable to control their diabetes with insulin.
Owen and his colleagues harvest islet cells from the pancreas of brain-dead donors and inject these cells into the liver of the diabetic patient. In the liver the islet cells "immediately begin producing insulin." But the key to success is the ability to transfer a sufficient number of islet cells. Owen says that more than 850,000 islet cells need to be transplanted before the patient can be insulin free. "This usually takes more than one transplant procedure," he says.
In this study, 90 islet cell transplants were performed in the 48 patients: 22 patients had two transplants, 10 had three transplants and 16 patients had a single transplant. "The transplant or infusion takes about 15 to 30 minutes," says Owen.
After the transplant all patients are placed on drugs that suppress the body's immune system so the transplanted islet ells won't be rejected.
Owen says that islet cell transplantation appears to help these patients even if they cannot stay off insulin. "When they have to take insulin again, they are able to maintain good metabolic control, which suggests that the goal of this therapy might be either insulin independence or good metabolic control," he says. He says that about half of the patients who still need insulin are taking "about as much as they were before the transplant, while half are taking much lower levels."
The study was funded by grants form the Juvenile Diabetes Research Foundation, the Alberta Foundation and Health Service Innovation Fund, and the Canadian Diabetes Association.