A new study from Stanford University has revealed a promising therapeutic method that could revolutionize the treatment of type 1 diabetes. This type of diabetes occurs when the body's immune system attacks the insulin-producing cells in the pancreas, mistakenly identifying them as foreign. In the study, researchers successfully prevented the onset of autoimmune diabetes in laboratory rats. All nine rats with long-term diabetes were cured after a simultaneous transplant of stem cells and pancreatic islet cells. This is a rare result in treating a highly complex disease. The researchers emphasize that all medications and treatments used in this experiment are already in clinical use for stem cell transplants, which increases the likelihood of their transition to human clinical trials. When these cells are lost, the body becomes unable to produce insulin and regulate blood sugar levels. The researchers were able to protect the rats from the disease or cure them completely by combining a transplant of two types of cells: hematopoietic stem cells (which build the immune system) and pancreatic islet cells (which produce insulin) from donor rats that were immunologically incompatible. Normally, such a scenario would be expected to result in the body rejecting the transplanted cells or the new immune cells attacking the recipient's healthy tissues. To the researchers' surprise, this did not happen at all; none of the rats developed graft-versus-host disease, where new immune cells attack the recipient's healthy tissues. The rats' original immune systems also stopped destroying the islet cells, and the animals did not require any immunosuppressive drugs or insulin for six months after the transplant, a long period in a rat's lifespan. This success is attributed to the rats developing a hybrid immune system, combining cells from both the donor and the recipient, which 're-educated' the immune system to stop attacking pancreatic cells. As Dr. Song K. Kim, a prominent expert in medicine, endocrinology, and aging, and director of the Stanford Diabetes Research Center, stated: "The potential of applying these results to humans is incredibly exciting." He explained that the key steps used in the experiment are already applied in treating other diseases, which strengthens the likelihood of their translation to human use in the future. This study builds on the results of a 2022 study, where researchers had induced diabetes in rats using toxins that destroy islet cells, then transplanted them with stem and islet cells from another donor after a mild preliminary therapy. However, the challenge in the new study was much greater: dealing with true autoimmune diabetes—the disease that occurs spontaneously due to an immune attack on islet cells without external intervention. In this case, the transplanted islet cells face two problems: they are foreign and may be rejected by the body, and they are also vulnerable to repeated autoimmune attacks. To solve this dilemma, researcher Preksha Bhagshandani and her colleague Stefan Ramos added a drug commonly used to treat autoimmune diseases to the preliminary treatment before the transplant.
