After decades of research, we now seem to be somewhat successful in transplanting insulin-producing islet cells into the human pancreas.
Type 1 diabetes is one of the major global health crises. It occurs when the body’s immune system attacks insulin-producing cells in the pancreas. Without insulin-producing cells, patients are at risk for blindness, disability, and an increased risk of Covid 19.
Human embryonic stem cells
Researchers at the Harvard Stem Cell Institute and the pharmaceutical company Vertex have discovered a way for insulin-producing pancreatic cells to grow from stem cells. These insulin-producing cells can be transplanted into the pancreas of patients with type 1 diabetes. If the study continues to be successful, researchers will develop a way to produce an unlimited source of pancreatic insulin-producing cells to improve or even definitively treat type 1 diabetes.
The process of developing the new method began with understanding what chemical signals are needed to guide stem cells to become insulin-producing cells. With the help of proper chemical signals, stem cells can be transformed into almost any other cell in the body.
To guide stem cells to become insulin-producing cells, Harvard researchers focused on understanding how the pancreas develops and discovering the mechanisms that the pancreas uses to produce these cells. After trying hard to determine which chemical signals could turn stem cells into insulin-producing islet cells, the Harvard research team finally succeeded.
Harvard then partnered with Vertex Pharmaceuticals to conduct the first phase of clinical trials to evaluate the safety of these cells in patients with type 1 diabetes. Preliminary trials provided guidelines for improving the methods used to produce islet cells. After the success of the initial safety trials, the cells were ready for use in clinical trials. The results of clinical trials were recently published in the Cell Stem Cell Journal.
One of the important issues in using stem cell-grown islet cells as a treatment for type 1 diabetes is that type 1 diabetes is an autoimmune disease. Thus, in people with type 1 diabetes, their immune system attacks any cell that resembles pancreatic islet cells.
For pancreatic islet cell transplantation to be successful in patients with type 1 diabetes, it is essential to use immunosuppressive techniques to prevent the immune system from invading islet cells. This was done by prescribing immunosuppressive drugs before injecting the grown islet cells into the laboratory. Following this process, the researchers monitored the patient’s insulin levels to determine if the transplanted islet cells were producing enough insulin to make a difference in the patient’s condition.
While none of the participants in the clinical study were completely free of insulin injections, the daily insulin requirements of all participants were significantly reduced. The results of these trials are promising. The cells successfully grew, transplanted, and produced insulin in response to the body’s normal glucose level.
In addition, the man who participated in the initial safety trials is now completely free of insulin injections. He can eat without the need to monitor or regulate his insulin levels and may be the first person to be reported to be permanently treated for diabetes.
The results of these trials are promising. However, there are issues with the success of stem cell-grown pancreatic cells in clinical applications.
The most obvious issue is the need for immunosuppressive drugs to limit the rejection of transplanted islet cells by the immune system. While these drugs enable successful transplantation of islet cells into patients with type 1 diabetes, they can have significant side effects such as inflammation, liver abscesses, and infection. Less severe side effects include loss of appetite, nausea and vomiting.
All study participants reported levels of adverse reactions to immunosuppressive drugs. Three participants experienced serious side effects, some of which caused them to withdraw from the study.
Overall, the results of the study are very promising and show significant progress in the treatment of diabetes. While more studies need to be done, we look forward to the day when stem cell-grown islet cells can completely replace the function of biological pancreatic cells, and millions of people around the world can live without the need for insulin injections.