An injection of stem cells could one day serve as a therapy for diabetes, a new study suggests, demonstrating yet another application for the versatile stem cell approach.
In the current issue of the Journal of the American Medical Association, a small Brazilian study reports that injections of stem cells harvested from a patient's own blood may keep type 1 diabetes at bay. The type 1 form of diabetes accounts for 5 to 10 percent of the approximately 21 million Americans with the disease.
The injections work by using the patient's own stem cells to replace the defective cells that cause the disease.
The study's findings could bring new hope to patients with type 1 diabetes because "for the first time in the history of diabetes, patients are now treatment-free for up to three years," says Dr. Richard Burt, the senior author of the study and chief of the division of immunotherapy at Northwestern University's Feinberg School of Medicine.
But some diabetes experts say more research is needed to confirm the benefits.
Dr. Jay Skyler, associate director of the Diabetes Research Institute in Miami and author of an accompanying editorial to the study, cautions that the study "is pioneering and provocative, but it is too small a number and too short a duration to allow people yet to change. … It needs confirmation."
And since the treatment involves destroying the patient's immune system before the patient receives the stem cells, critics fear the risks of the treatment may outweigh its potential benefits.
Type 1 diabetes is caused by the destruction of the insulin-producing cells in the pancreas by a person's own immune cells -- what Burt calls the "police force" of the body.
The disease is usually diagnosed in childhood or adolescence. Patients normally face a lifelong regimen of insulin replacement, either through a continuous pump or frequent self-administered insulin shots.
Insulin is critical to how the body uses sugar. Without it, unused sugar, or glucose, builds up in the body.
Over the long term, chronically high levels of glucose can damage the eyes, heart, kidneys and nerves -- possibly resulting in blindness, heart disease, kidney failure and loss of sensation.
Currently, there is no cure for type 1 diabetes, and onIy strict control of glucose levels can reduce the complications of this disease. But Burt and his colleagues hope that these stem cell injections could be a first step.
Though this is the first time researchers have used this particular stem cell approach for diabetes, such injections have been found to be promising in the treatment of many other diseases in which the immune system attacks the patient's own body, such as rheumatoid arthritis and multiple sclerosis.
First, doctors collect the patient's own stem cells from his or her blood. They then destroy the patient's existing immune cells with chemicals, after which they use the harvested stem cells to rebuild the patient's immune system.
Unlike the old immune cells, the new ones will not attack the insulin-producing cells in the pancreas -- or at least, that's what researchers hope.
But is this study good enough? Skyler cautions that the research is limited by three things: small numbers, short duration and no control group.