The results of an early clinical trial have shown that infusion of immunosuppressive T cells is safe and that these cells can act in patients for at least one year.
These findings support further testing of such a method known as adoptive transfer and look forward to extending the results obtained in cancer immunotherapy to the field of diabetes treatment. Type 1 diabetes is an autoimmune disease that usually affects children and causes the immune system to disrupt the cells that produce insulin in the pancreas. Researchers have long been trying to develop treatment methods that can correct or replace regulatory T cells; regulatory T cells are a class of T cells that are immune to the immune response, and that cells are considered defective in the body of diabetic patients.
Jeffrey Bluestone and colleagues conducted Phase I clinical trials of adoptive transfer of regulatory T cells in adult patients with advanced diabetes mellitus at stage I4. The researchers searched the patient’s blood for regulatory T cells, allowed to grow in the laboratory, and then injected them back into the same patient’s body. These regulatory T cells prepared for transfection in culture are shown to enhance their inhibitory activity compared to their unpredictable counterpart cells, indicating that these cells have a defective immune response that may have been repaired.
Tracing of these adoptive transferred cells shows that they can live for a long time and survive in some patients’ circulatory systems for more than a year. None of the patients had treatment-related side effects or complications. The researchers said that adoptive transfer of regulatory T cells or other stimuli can stimulate the activity of these cells combined with immunotherapy therapy for type 1 diabetes.