Islet Transplantation for Type 1 Diabetes

An experimental procedure known as pancreatic islet transplantation could change the lives of people suffering from type 1 diabetes by allowing them to stop using insulin for up to ten years. While the procedure is still experimental in the U.S. and researchers are testing it in different medical centers across the country, in other countries, it has already been approved and results have been encouraging.

Understanding the Problem: Type 1 Diabetes

In a healthy person, beta cells in the pancreas produce and store insulin, releasing it when blood glucose levels rise. Insulin’s role is to help the body’s cells absorb glucose from the blood, which is then converted into energy.

If there isn’t enough insulin, or it is absent, the signals telling special transporter proteins in cell membranes to allow glucose to enter the cell never reach the intended target, which prevents glucose from being absorbed. In some cases, the cells’ sensitivity to insulin decreases, which leads to the same result.

In patients with type 1 diabetes, the pancreas no longer produces insulin because the immune system has attacked the beta cells and destroyed them. Thus, people with this disease have to take insulin daily, so the glucose in their bloodstreams doesn’t reach fatal levels.

What Is Pancreatic Islet Transplantation?

Pancreatic islets are microscopic clusters of cells located throughout the pancreas. These islets contain various types of cells, including beta cells.

Transplantation involves taking islets from an organ donor and transferring them to another person. Ideally, these islets begin to produce and release insulin not long after they are transplanted, but it can take time for them to begin to function at optimum levels, as it takes a while for new blood vessels to grow. Until the islets are fully functional, patients still have to take insulin.

The problem with this procedure and the reason the results aren’t permanent or always guaranteed is that the patient’s immune system could attack the new islets, just as it did the original ones. At the moment, most of the people who undergo this procedure need at least two transplants to be able to keep their blood glucose levels within a normal range over the long-term.

However, Dr. Michael Rickels, an associate professor of medicine at the University of Pennsylvania, conducted a study in which he and his colleagues used a new protocol to transplant pancreatic islet cells. The islets were transplanted three days after extraction instead of right away, which seemed to improve results as every patient involved in the study was able to go without insulin for at least a year after only one transplant.

The Future of Pancreatic Islet Transplantation in the United States

There are two human clinical trials being conducted in the United States, and once they are completed, researchers will submit the results to the Food and Drug Administration for analysis. If the FDA approves the procedure, pancreatic islet transplants could become the norm in as little as two to three years.

However, it’s important to note that this procedure will only be able to help people suffering from type 1 diabetes, which represents only 5 percent of diabetics according to the American Diabetes Association. Unfortunately, pancreatic islet transplantation cannot help those with type 2 diabetes because they already produce insulin. Their bodies are simply unable to use it properly.

So, while pancreatic islet transplantation may soon change the lives of many people suffering from type 1 diabetes, it certainly isn’t a magic bullet that will cure all diabetics.