A patient who received a stem cell transplant has seen his type 1 diabetes disappear so that he no longer has to inject large amounts of insulin daily. If this approach is successful in other patients, type 1 diabetes may become a thing of the past for 10 percent of diabetics.
A 64-year-old American man with type 1 diabetes, an autoimmune form of the disease in which insulin-producing cells are destroyed, can regulate his insulin production and blood sugar levels without the use of drugs by injecting stem cells into his bloodstream. Vertex, the biotech company leading the clinical trial, took a cellular approach. In the pancreas, only the β cells in Langheran islets secrete insulin. Using a protocol developed at Harvard, embryonic stem cells were transformed in vitro into pancreatic β-cells. They were injected into the bloodstream and replaced the defective pancreatic cells. This 64-year-old American is the first patient for whom the protocol has been successful.
A cell transplant to correct type 1 diabetes
His levels of C-peptide, a small protein synthesized at the same time and in the same amount as insulin and which serves as a marker of β-cell activity in the pancreas, increased from 0 to 280 and 560 pmol/L during a fasting and feeding period, respectively. The patient, who before the transplant needed to inject 30-34 units of insulin per day to survive, now only needs three units. The next step will be to repeat the trial with 17 other patients treated at different centers.
If the researchers can reproduce the same results in other patients, type 1 diabetes could be cured using a differentiated stem cell transplant, but at the cost of lifelong immunosuppressive treatment. The researchers are working to make the immune system tolerant to the transplanted stem cells. ViaCycle, another company specializing in the treatment of type 1 diabetes, has tested various devices to protect stem cells from the immune system but without convincing results so far.