Re: will there be a cure for diabetes in the near future?

Dear Eric- I am sorry that you have diabetes. It can be a frustrating disease, especially for a young person. Before I talk about possible cures, let me remind you what diabetes is (you probably already know, but it will make the discussion of cures clearer). Juvenile (or Type I) diabetes is the result of the immune system attacking the cells of the pancreas that make insulin, the beta-islet cells. Why this attack happens is unclear, although some people believe that it may be related to an immune response that has gone crazy after an infection, likely viral (for examples see references 1&2). This is in contrast to Type II diabetes, often referred to as adult-onset diabetes (although it can certainly occur in children and is becoming more prevalent in young adults), which is often a secondary result of obesity and is characterized by so-called "insulin resistance." Type II diabetics have functioning islet cells, and make insulin, but the cells that respond to the insulin are less responsive because they have downregulated the insulin receptor.

Due to the differences in Type I and Type II diabetes, the potential cures and treatments are quite different. A short-term treatment (not a cure) of diabetes is the development of pumps that can be placed under the skin or hooked into a permanent port. These pumps deliver insulin in small doses all day long, preventing the spikes and valleys of insulin delivered by shot. They can be programmed to respond to blood sugar levels. They also are nice in removing the need for a needle (references 3,4). However, they do have the drawback of having to be implanted under the skin, a surgical procedure.

In the longer term, many in the field of diabetes research hope to be able to conduct islet transplants. Currently, islet transplantation is limited by the availability of human islet donors, and a single donor's islets are not sufficient to allow a recipient to live free of insulin therapy. In order to overcome this barrier, some researchers are trying to improve the survival of the islets during transplantation (5). Another problem is that after islet transplantation, immunosuppression is required to prevent rejection (6). Some researchers are trying to get around these problems by investigating whether pancreatic precursor cells (pancreatic stem cells) can be grown into functioning insulin-producing cells, while others are investigating using islets from other species (like we currently use pig heart valves to repair some heart defects) (6, 7).

While islet transplantation has been achieving some success in clinical trials, the underlying problem of autoimmunity remains in Type I diabetes. This means that even after a successful islet transplant, the patient will have to remain on immunosuppressive drugs, with all of their side effects, for life. Given this problem, some researchers have been focusing on trying to convince the immune system to not attack the islets any more. They are trying to do this by gene therapy and "vaccines." These vaccines are different from the usual vaccines in that they're trying to change an ongoing immune response, rather than boosting an immune response to fight infection (8,9).

In all, with our growing understanding of both Type I diabetes and the immune response, there is the hope that a cure for diabetes will come within our lifetimes. Let us hope so.

I hope this has answered your question, Eric. Take care.

Sincerely,
Ingrid
MadScientist

References:
1) Gupta M, Nikitina-Zake L, Landin-Olsson M, Kockum I, Sanjeevi CB. Coxsackie virus B antibodies are increased in HLA DR3-MICA5.1 positive type 1 diabetes patients in the Linkoping region of Sweden. Hum Immunol. 2003 Sep;64(9):874-9.
2) Cabrera-Rode E, Sarmiento L, Tiberti C, Molina G, Barrios J, Hernandez D, Diaz-Horta O, Di Mario U. Type 1 diabetes islet associated antibodies in subjects infected by echovirus 16. Diabetologia. 2003 Oct;46(10):1348-53. Epub 2003 Jul 29.
3) Couper JJ, Prins JB. 2: Recent advances in therapy of diabetes. Med J Aust. 2003 Oct 20;179(8):441-7.
4) Schaepelynck Belicar P, Vague P, Lassmann-Vague V. Reproducibility of plasma insulin kinetics during intraperitoneal insulin treatment by programmable pumps. Diabetes Metab. 2003 Sep;29(4 Pt 1):344-8.
5) Embury J, Ribeiro M, Klein D, Pileggi A, Molano RD, Fraker C, Kenyon N, Ricordi C, Inverardi L, Pastori RL. Transduction of tat/ptd antiapoptotic fusion proteins in pancreatic islets. ScientificWorldJournal. 2001 Jan 1;1(1 Suppl 3):41.
6) Inverardi L, Kenyon NS, Ricordi C. Islet transplantation: immunological perspectives. Curr Opin Immunol. 2003 Oct;15(5):507-11. 7) Rogers SA, Liapis H, Hammerman MR. Intraperitoneal transplantation of pancreatic anlagen. ASAIO J. 2003 Sep-Oct;49(5):527-32.
8) Petrovsky N, Silva D, Schatz D. Vaccine therapies for the prevention of type 1 diabetes mellitus. Paediatr Drugs. 2003;5(9):575-82.
9) Krueger T, Wohlrab U, Klucken M, Schott M, Seissler J. Autoantigen- specific protection of non-obese diabetic mice from cyclophosphamide- accelerated diabetes by vaccination with dendritic cells. Diabetologia. 2003 Oct;46(10):1357-65. Epub 2003 Aug 20.