Pancreatic islet cell transplant therapy offers a promising option for people with type 1 diabetes who struggle with severe low blood sugar or unstable glucose levels. In this procedure, donor islet cells are infused into the liver to help the body naturally produce insulin again, decreasing the frequency of monitoring and dependency on diabetes supplies. While not a cure, islet transplantation can significantly improve the quality of life for eligible individuals by restoring more stable blood sugar control. Here, we'll provide more detail on how the procedure works, common risks and challenges, and how it compares to other treatment options.
In this article, you'll learn:
- What pancreatic islet cells are and how they regulate blood sugar.
- How islet cell transplants work and how they can help people with type 1 diabetes.
- Who qualifies for an islet cell transplant and why eligibility is limited.
- The benefits of the procedure, including improved blood sugar control and reduced severe hypoglycemia.
- The risks and challenges, such as immune rejection, lifelong immunosuppressants, side effects, and donor shortages.
- New research and FDA-approved therapies that are advancing islet transplantation.
- How islet cell transplants compare to other diabetes treatments like insulin therapy, CGMs, and artificial pancreas systems.
- Why islet transplants are promising, but not a cure, and how to discuss options with your healthcare team.
Understanding Pancreatic Islet Cells and Their Role
Pancreatic islets, also commonly referred to as islets of Langerhans, are groups of specialized endocrine cells within your pancreas. They're responsible for producing hormones (like insulin) that enter the bloodstream and help control blood glucose levels. Each islet contains several different types of hormone-producing cells, each with its own important function:
- Beta cells: Produce insulin, the hormone that lowers blood sugar by helping glucose enter the body’s cells. These cells are destroyed in type 1 diabetes.
- Alpha cells: Produce glucagon, which raises blood sugar when levels drop too low.
- Delta cells: Release somatostatin, a hormone that helps regulate the activity of both insulin and glucagon.
- PP (F) cells: Produce pancreatic polypeptide, which supports digestive function and appetite regulation.
- Epsilon cells: Produce ghrelin, a hormone involved in hunger and metabolism.
Together, these act like your body’s built-in glucose management system, constantly adjusting hormone levels to keep blood sugar within a safe range. When beta cells stop working, as in type 1 diabetes, this system breaks down, leading to uncontrolled blood glucose and a lifelong need for insulin therapy.
What is an Islet Cell Transplant and How Can it Help With Diabetes Management?
In type 1 diabetes, the body's immune system destroys the beta cells, which are responsible for producing insulin in the pancreas. This leads to a dependence on external insulin injections or pumps to balance blood sugar. Pancreatic islet transplantation takes islet cells from a donor's pancreas and transplants them into people with type 1 diabetes to help restore insulin production in the recipient. The healthy islet cells are injected into the portal vein, which carries blood to the liver.
Pancreatic islet cell transplantation has been shown to help the treatment of diabetes, and clinical results show that it can improve blood glucose control, reduce severe hypoglycemia, and even enable insulin independence.
However, these results are not always permanent and may require multiple injections to continue reaping the benefits. There is also a shortage of donor islet cells, and some individuals may experience an immune rejection of transplanted cells. Although research on stem cell therapy is underway, this approach to islet transplants is still being tested. If you're interested in learning more about available transplant programs for islet cells, talk to your doctor or diabetes team.
Who Is Eligible for an Islet Cell Transplant?
Not everyone is a good candidate for this transplantation, so it's important to discuss your circumstances with your doctor. In most cases, doctors will consider an individual for an islet transplant if the possible benefits outweigh the risks. This tends to include people who:
- Have type 1 diabetes with severe hypoglycemia, especially those who experience frequent episodes of low blood sugar that are difficult to detect or manage.
- Struggle with hypoglycemia unawareness, meaning they no longer feel or recognize early warning signs of dangerously low blood sugar.
- Have “brittle” diabetes, where blood sugar levels swing unpredictably despite careful monitoring and consistent insulin use.
- Cannot achieve stable glucose control even with advanced technologies like insulin pumps, continuous glucose monitors, or hybrid closed-loop systems.
- Are otherwise healthy enough to undergo the procedure and the long-term use of immunosuppressive medications needed to prevent rejection.
- May be preparing for or recovering from a kidney transplant, as islet transplantation is sometimes considered alongside or after kidney transplantation in people with advanced diabetes complications.
Risks, Challenges, and Complications
In many transplant recipients, the procedure temporarily reverses diabetes, which can allow individuals to live without their (or with fewer) diabetes supplies. However, this outcome is not guaranteed, and even when successful, the effect may be temporary. Over time, transplanted islet cells can lose function or be destroyed by the immune system, meaning some individuals may return to insulin therapy. This unpredictability can be challenging if someone expects the transplant to be a permanent cure.
When successful, recipients will also need to take immunosuppressive medications for the rest of their lives to help reduce the risk of rejection. These medications have their own side effects, ranging from mild to severe. Whether the benefits outweigh the risks varies from person to person and requires careful medical evaluation. Some of these risks include:
- Increased infection risk
- High blood pressure
- Kidney strain or reduced kidney function
- Elevated cholesterol or triglycerides
- Gastrointestinal issues
- Increased risk of certain cancers with long-term use
Another complication is the fact that there's a shortage of donor organs to provide islet cells. Although current programs are investigating the possibility of "growing" insulin-producing cells in a laboratory or producing them from stem cells, there's still work that needs to be done.
Additional risks or challenges that are associated with islet cell transplants include:
- Bleeding or blood clots related to the transplant procedure, mainly because islets are infused into the liver.
- Liver complications, including portal vein thrombosis or elevated liver enzymes.
- Allergic or inflammatory reactions during or after infusion.
- Not enough islet cells survive the transplant, resulting in limited or no improvement in blood sugar control.
- Dependence on multiple donor organs, since some patients may require more than one islet infusion for adequate insulin production.
Emerging Research and Innovations
Pancreas and islet cell transplantation was considered experimental for many years and was only allowed in clinical trials. However, in 2023, the U.S. Food and Drug Administration (FDA) approved the first cell therapy made from islets of deceased donors for use in islet transplantation. According to the FDA News Release, "Lantridra is the first allogeneic (donor) pancreatic islet therapy... approved for adults with type 1 diabetes who are unable to achieve target glycated hemoglobin (average blood glucose levels) because of current repeated episodes of severe hypoglycemia (low blood sugar) despite intensive diabetes management and education."
Islet Cell Transplants vs Other Diabetes Treatments
The benefit of being an islet transplant recipient is that the procedure is relatively easy and does not require you to undergo major surgery. It involves a small injection of cells from the pancreas of the donor; therefore, no anesthesia or incisions are necessary. However, for those who do not find ongoing success with this therapy, a pancreas transplant may be an alternative option. This is often done in individuals who have chronic pancreatitis or when other, advanced treatments aren't working. The complete removal of the pancreas will be performed during the transplant surgery, and a healthy functioning pancreas will be transplanted. Some individuals may also undergo a total pancreatectomy with islet cell infusion to help increase the success of the treatment.
While islet and pancreas transplants offer potential for insulin independence, they are not the only treatment options available for diabetes. Many individuals manage the disease effectively with less invasive therapies, including:
- Insulin therapy: The most common treatment for type 1 diabetes. It includes multiple daily injections or the use of an insulin pump to mimic natural insulin release.
- Continuous glucose monitors (CGMs): Small wearable devices that track blood sugar levels around the clock, helping reduce hypoglycemia and improve glucose management.
- Hybrid closed-loop systems: These are artificial pancreas systems that connect an insulin pump with a CGM, allowing automated insulin delivery based on real-time glucose data. They significantly reduce the day-to-day requirements for diabetes management.
- Advanced insulin formulations: Ultra-rapid or long-acting insulins can better mimic natural blood sugar patterns, improving control and convenience.
- Lifestyle management: Nutrition planning, regular exercise, stress reduction, and ongoing diabetes education remain central to maintaining healthy blood sugar levels.
The research involving islet cells represents an exciting and evolving option for people with type 1 diabetes, and while it offers the potential for more natural insulin production and improved glucose control, it also comes with challenges. To determine the best treatment for your situation, it's important to work with your doctor and discuss all of your options. Byram Healthcare carries a wide range of diabetes products to help you stay in control and live confidently. To learn more, contact Byram’s diabetes helpline: 1-877-902-9726, ext. 43397.
