Islet Transplant for Type 1 Diabetes

What Is Islet Cell Transplantation?

Islet cell transplantation is a procedure in which beta cells from a deceased donor are transplanted into people with type 1 diabetes. Pancreatic islets, or islets of Langerhans, are small groups of cells in the pancreas. These cells play a very important role in regulating blood sugar levels by releasing hormones. The main hormones secreted by pancreatic islets are insulin, which reduces blood sugar, and glucagon, which increases blood sugar. These islets are crucial for maintaining energy balance in the body and play a vital role in preventing conditions such as diabetes.

After transplantation, the beta cells begin producing insulin, thereby reducing the need for daily insulin injections. Special enzymes help remove beta cells from the donor. To be effective in the recipient, people receiving the transplants require around 10,000 islet cell equivalents from two donors.

How Common Is Islet Transplantation?

Islet transplantation is not very common due to the limited availability of donors and the need for lifelong immune suppression. It is primarily done in research centers or specialized centers for select patients with type 1 diabetes who have severe fluctuations in blood sugar. Although it has been found to be successful, its application is limited compared to other treatments for diabetes, such as insulin therapy or pancreas transplantation.

How Is Islet Cell Transplantation Performed?

• First, the patient is given a local anesthetic and a sedative.

• Islets are extracted from an organ donor's pancreas. After being cleaned and processed, the islet cells are taken from a donor and transplanted to the recipient. After being implanted, these islets' beta cells start producing and releasing insulin.

• A catheter, or a small plastic tube, is inserted through the upper abdomen into an important vein called the portal vein of the liver.

• Then, the islets are infused into the vein through the catheter.

• Sometimes, a surgeon may also do the procedure by infusing the donor’s cells into the recipient’s liver after giving a small incision under general anesthesia.

• After implantation, the beta cells start to produce and release insulin into the body.

• Insulin is released by the islets shortly after transplantation. Full islet function and the development of new blood vessels connected to the islets, however, require time.

• Insulin is typically administered until the islets are completely functional, and the doctor will order numerous tests to monitor blood glucose levels following the transplant.

What Are the Benefits of Islet Transplantation?

The aim of Islet cell transplantation is to improve the quality of life of patients and reduce recurrent episodes of hypoglycemia (low blood sugar). Successful transplantation involving beta cells of the pancreas offers several advantages.

• Islet transplantation aims to infuse enough islets to regulate blood glucose levels without the need for insulin injections.

• Improved glucose control and the avoidance of potentially hazardous hypoglycemia episodes could be additional advantages.

• A successful transplant may lower the risk of complications related to diabetes, such as heart disease, kidney disease, and damage to the nerves or eyes, because effective blood glucose control can slow or prevent the progression of these conditions.

What Are the Risks of Islet Transplantation?

Along with benefits, the procedure also has some involved risks that include:

• Rejection of the new cells occurs as the body’s immune system considers any cell that is not a part of the body as foreign and tries to destroy it. To counteract this, doctors advise using immunosuppressive or anti-rejection medicines that lead to severe side effects. Also, a few researchers believe that long-term use of immunosuppressive medications can increase the risk of infections and a few types of cancers.

• Formation of blood clots or bleeding after surgery.

• Lack of available pancreas donors.

• The need to receive two to three transplants to achieve complete insulin independence.

Who Are Candidates for Islet Transplantation?

• People with type 1 diabetes for five years or more can undergo a pancreatic islet cell transplant.

• The candidate must also be within the age bracket of 18 to 65 years.

• It can be carried out in patients who repeatedly experience low blood sugar attacks or have an increased risk for complications due to diabetes, like kidney failure.

How Successful Is Islet Transplantation?

Islet transplantation has shown mixed success. Although some of the patients have maintained long-term independence from insulin, results have been variable. Investigations found that 50 percent of recipients remained insulin-free after one year, 30 percent after three years, and 25 percent after five years. The procedure could enhance blood sugar control and decrease episodes of severely low blood sugar but was dependent on factors such as how the immune response would be and the need to be on lifelong anti-rejection medication.

What Is the Future of Islet Cell Transplantation Research?

Two key areas under research in the case of islet cell transplantation are:

• Acquiring sufficient islet cells - The prime problem is sourcing sufficient islet cells for transplantation, which usually requires multiple donors. Since human donors alone cannot meet demand, scientists consider other sources, including fetal tissue, animals like pigs, and laboratory-produced human islet cells.

• Prevention of rejection - The newer anti-rejection drugs, including Tacrolimus and Rapamycin, are less toxic than the older drugs, including Cyclosporine and Prednisone. Techniques to avoid or eliminate immunosuppressive drugs are also under development, such as coating islet cells with a protective gel that prevents the immune system from attacking the cells.

Conclusion

Islet cell transplantation is a field that gives hope to patients with type 1 diabetes. However, as any procedure has its benefits and risks, so does islet cell transplantation. Research is going on to improve the success of the procedure. The main aim is to prevent the rejection of the islet cells and reduce the side effects. Also, there are more recipients in need of transplantation than available donors. Therefore, studies and testing are being done to obtain islet cells from a live person’s pancreas or other animals.

A successful transplant can help people with type 1 diabetes lead a better quality of life with a lesser need for insulin shots, constant monitoring of blood sugars, and long-term diabetes-related complications. To know more about the procedure, you can consult our Diabetic specialist.

Key Takeaways

• Islet transplantation is a procedure to treat type 1 diabetes in which a patient's liver is infused with islet cells that have been extracted and purified from the pancreas of an organ donor as part of an experimental procedure called islet transplantation.

• Eliminating hypoglycemia episodes and achieving good overall blood sugar control with minimal or no insulin injections is the main objective of islet transplantation.

• Benefits could include better glucose regulation and the avoidance of potentially harmful hypoglycemic episodes. Maintaining adequate blood glucose control can delay or stop the development of diabetic complications.