What Is the Edmonton Protocol?

An innovative surgical treatment for type1 diabetes became known as the Edmonton protocol because Drs. James Shapiro and Jonathan Lakey from the University of Alberta in Edmonton developed the procedure in the late 1990s. The Edmonton protocol involves transplanting cells that produce blood sugar-regulating hormones into the pancreases of patients with type 1 diabetes. More than half of the patients who have undergone the Edmonton protocol have had their diabetes brought completely or partially under control without insulin for at least one year.

Type 1 Diabetes

• People with type 1 diabetes lack adequate concentrations of insulin in their bloodstreams. Insulin binds with sugars that the body produces from food and allows those sugars to penetrate muscle cells. When insulin concentrations remain chronically low, people develop a condition called hypoglycemia and experience extreme hunger and thirst, rapid weight loss, blurred vision and fatigue. Over the long term, people with type 1 diabetes can experience irreversible damage to their hearts, blood vessels, eyes, kidneys, skin, feet and hearing. Severe hypoglycemia can cause organ failure and death.

Pancreatic Islet Cells

• Specialized cells in the pancreas known as beta cells produce insulin. Companion alpha cells that produce the hormone glucagon, which increases the amount of sugar in the blood stream, join with beta cells to make up clusters known as the Isles of Langerhans. Doctors and scientists refer to alpha and beta cells as pancreatic islet cells.

What the Edmonton Protocol Involves

• The Edmonton protocol involves careful selection of pancreatic islet cell recipients, the careful selection of cell donors, a surgical injection and the administration of three immune system-suppressing drugs. To qualify for the procedure, a patient must have had type 1 diabetes for at least five years, have difficulty recognizing the signs of hypoglycemia and suffer serious complications from hypoglycemia despite using insulin as prescribed.

  Pancreatic islets cells for transplant must be extracted from pancreases removed from recently deceased adults. Individuals who are between 51 and 65 years of age and who have a body mass index of at least 24 at the time of death make the best donors of pancreatic cells. Two pancreases are needed to supply enough islet cells for one transplant recipient.

  To transplant the islet cells, a surgeon inserts a needle into the portal vein of the recipient's pancreas and injects the cells via a catheter. The recipient receives a local anesthetic before the injection, and the surgeon uses a scanning x-ray to find the portal vein and place the needle. Following the surgery, the transplant recipient takes daclizumab (Zenapax), sirolimus (Rapamune) and tacrolimus (Prograf) to prevent rejection of the transplanted cells.

Risks and Complications of the Protocol

• Because accessing the Isles of Langerhans requires inserting a needle around and under the liver, Edmonton protocol patients run a risk of having their liver punctured during the procedure. Other surgery-related risks and complications include infections, clots in the portal vein, excessive bleeding from the liver and veins in the back of the eye, overproduction of cholesterol by the liver and spikes in blood pressure. No Edmonton protocol patients have died from surgical complications.

Outcomes for Patients

• Shapiro and Lakey reported Edmonton protocol patient outcomes in the September 28, 2006, issue of the New England Journal of Medicine. At that point, 36 people had undergone the pancreatic islet transplantation procedure. Sixteen of those patients were able to discontinue injecting insulin for at least one year, and another 10 percent of patients were able to reduce the number of insulin injections they needed each day. The remaining 10 patients rejected the transplant islet cells. In April 2009, when the developers of the Edmonton protocol marked the 10th anniversary of the procedure, Shapiro noted that the 110 patients his team had treated had achieved outcomes similar to those reported in 2006.