Diabetes type 1 (juvenile diabetes or "juvenile diabetes") is a disease of the immune system and the pancreas. A misguided immune defense destroys the islet cells of the pancreas. Patients suffering from this type of diabetes must inject themselves with insulin every day for a lifetime, which is formed by the pancreas in healthy individuals. An alternative method to insulin injection is islet cell transplantation. Insulin is the only hormone in the human body that can move sugar from the blood into the cells. Without insulin, the sugar level in the bloodstream is too high. On the other hand, the organs on the other side are literally starving to death.
Transplant - an alternative?
Already today many of these people can be given a life without injections by the implantation of a foreign pancreas. The price is a non-safe operation and the lifelong use of drugs that suppress the immune system. It is easier and less risky to transplant diabetics only insulin-producing islet cells. Nevertheless, so-called immunosuppressants must also be given here to suppress the body's defense - the islet cells are not supposed to die as a result of the immune system.
Islet cell transplantation - how does it work?
For this purpose, the islet cells in the laboratory are removed from a donor pancreas, cleaned and then injected into the recipient with local anesthesia via a cannula in the portal vein. From there, they migrate into the liver, remain in the liver tissue and immediately begin to monitor the blood sugar level and, if necessary, to disperse insulin. In the clinic, this form of therapy has been carried out since the eighties. It is particularly suitable for patients who are not yet suffering from the after-effects of diabetes (for example kidney damage). The best results are currently being achieved with treatments according to the so-called Edmonton protocol, which includes a special treatment of islet cells and post-treatment. This process was developed in Gießen. Patients stay in the clinic a few days after the procedure using this method. In 80 percent of cases, enough islets will reach their target in the liver and successfully begin their insulin production. Many of the patients treated in this way can live a normal life for years. Often, the first signs of diabetes mellitus follow-up develop during this time. But even if island cell transplantation does not achieve complete independence from insulin - meaning that small amounts of insulin still need to be injected daily - the function of the islands still exerts very favorable effects on the metabolism.
And the future of this method ...
Research is currently focusing on improving this treatment method. For example, it is being worked on whether organs other than the liver will be suitable as "guest sites" for islet cells in the future. In the liver, the new islets there are threatened by environmental toxins and drugs. Alternatives could include the abdominal cavity, the spleen, the network surrounding the organs (omentum) or the kidney capsule.
Pancreatic cells, which are now used for islet cell transplantation, are derived from human organ donors. Since a large number of cells have to be transplanted and many are lost during reprocessing, work is underway to work on porcine islet cells in future (so-called xenotransplantation). This could solve the problem that there are currently not nearly enough donor pancreas available to help anyone who wants to treat.
Another way of the future is the cultivation of islet cells in the laboratory. The starting point is the so-called stem cells, the all-rounder among the tissue cells. They are not yet specialized, so a stem cell can make both a bone and a nerve. Or just an island cell. Stem cells are obtained either from embryos. But this is an ethically highly controversial matter. In Germany, working with these stem cells is kept to a minimum.
The so-called adult stem cells are also found in the adult body. They may be researched and worked with, but they are a bit more limited in their diversity than the embryonic stem cells. But if and when the masses will benefit from this research is still completely open. So, just how the future of diabetes treatment will look like can only be decided by time.
How often is the treatment being used?
Between 1974 and 2000, a total of 445 human islet cell transplantations were reported in patients with type 1 diabetes. That is, at the moment, this method is limited to a few isolated cases. Again, the future will show if this can be an alternative for many type 1 diabetics. Further information on islet cell transplantation is available from the German Diabetes Research Institute.