Stem cells develop in the bone marrow, as the earliest stage of a blood cell's development. Stem cells are able to renew themselves through cell division, and they can differentiate into different types of blood cells -- red cells, white cells and platelets. Various forms of stem cell transplantation have proven effective in treating a number of diseases.
A new study published in April 2007 suggests that stem cell transplantation may help patients with type 1 diabetes reduce the need for insulin.  This is the first study to combine stem cell transplants with immuno-supression in patients with diabetes.
The study involved fifteen patients with type 1 diabetes, ranging in age from 14 to 31. All of the patients were newly-diagnosed, and were identified before the insulin-producing cells in the pancreas were destroyed by the body's immune system. Stem cells were harvested from the patients' bone marrow, and they were then given several days of high-dose chemotherapy. The chemo treatments shut down the patients' immune systems, which stopped the destruction of the insulin-producing cells. The patients were then injected with their own harvested stem cells, which built a new, healthier immune system.
Thirteen of the patients responded to the treatment, and no longer need insulin. The study's first author, Dr. Júlio Voltarelli of the University of São Paulo says that the thirteen patients "live a normal life without taking insulin. They all went back to their lives."  Some patients have been insulin-free for 20 months.
The research was done as an "observational study", and did not include a control group for comparison. Therefore, the study is not definitive, although it points the way towards further developments. 
- ↑ Voltarelli, Júlio; C. Couri, A. Stracieri, M. Oliveira, D. Moraes, F. Pieroni, M. Coutinho, K. Malmegrim, M. Foss-Freitas, B. Simões, M. Foss, E. Squiers, R. Burt (April 2007). "Autologous Nonmyeloablative Hematopoietic Stem Cell Transplantation in Newly Diagnosed Type 1 Diabetes Mellitus". The Journal of the American Medical Association 297 (14): 1568-1576.
- ↑ "Study Suggests New Avenue on Diabetes", The New York Times. April 11, 2007.
- ↑ "Stem Cell Transplants In Diabetes Type 1 Patients Kick Starts Own Insulin Production", Medical News Today. April 11, 2007.