Treatment of diabetes with stem cells
Diabetes (or diabetes) is one of the most common chronic diseases in human societies today. This disease is also called “silent killer”. People with the disease are at risk for cardiovascular problems, strokes, kidney failure, and eye diseases (and even blindness) in the long run.
Fortunately, by controlling this disease, these complications can be prevented to some extent, but unfortunately, there is no definitive cure for this disease yet. It is estimated that in our country in the next two decades, 20% of the population will be infected with this disease. There are different types of this disease, but one of the most common types, called type 1 diabetes, is caused by the autoimmune destruction of insulin-secreting cells (beta cells) in the pancreas. Therefore, scientists have always thought that these patients could be treated by replacing or transplanting these cells. The first human studies of beta cell transplantation were performed in Pittsburgh, USA in the 1990s.
In 2000, a group in Edmonton, Canada demonstrated that beta cell transplantation could cure the disease. Despite the successful and short-term results, unfortunately this method was not successful in the long run. To date, about 2,000 people around the world have been treated in this way with no long-term results.
There are several reasons for this: It is very difficult to separate beta cells from the pancreas in the first place, and sometimes not enough cells can be extracted. Second, because these cells are not from the recipient’s own body, the body tends to destroy or reject them. Therefore, anti-transplant drugs are needed, which sometimes have destructive effects on beta cells. Therefore, beta cells can be an effective treatment for diabetes if they can be found in many sources of beta cells and the need for rejection drugs can be met. About 10 years ago, researchers at the Harvard University Diabetes Center in the United States showed that under certain conditions, embryonic stem cells could be differentiated into pancreatic stem cells and eventually into beta cells. This important step solved the problem of having access to a sufficient number of stem cells. These scientists showed that this method can cure diabetes in laboratory animals. The question now was how to hide these cells from the immune system so that they would not be destroyed. The scientists then succeeded in placing these cells in special capsules so that only the food and secretions of these cells could pass through these membranes and not the immune cells. In this way, the beta cells inside the capsule are able to secrete insulin by detecting sugar in the tissue. This insulin crosses the membrane and enters the bloodstream. Using this method eliminates the need to take anti-transplant drugs. Recently, a knowledge-based company called Viacyte in San Diego, USA, used this method to treat patients with type 1 diabetes. In this method, first using embryonic stem cells, they are first differentiated into pancreatic stem cells and beta cells. The cell is then placed in a special capsule to protect it from being damaged by the immune system. These capsules are then placed under the patient’s skin. The cells inside the capsule secrete insulin under the skin by detecting sugar. The results of this study were recently presented at the American Diabetes Association. Of the 19 patients treated in this way, two patients had normal blood sugar after two years and their diabetes was cured. Of course, this method requires a lot of research to be completed, but the initial result has been very promising. Although many of these cells are still alive after two years, in some of these patients they do not function properly due to an inflammatory reaction around the capsule. More work on the nature of the capsule can solve this problem. Preliminary studies showed that this was a nonspecific reaction against the membrane (capsule) and not against beta cells. Although this method is still in its infancy, the first showed that it can be done in humans and is safe. Second, it could raise hopes that by completing it in the future (using stem cells without the need for anti-rejection drugs) could cure diabetes.
Dr. Reza Saidi Firoozabadi – Transplant Surgeon