Diabetics cured

Diabetics cured by stem-cell treatment
Patients given transfusions drawn from own blood

Diabetics using stem-cell therapy have been able to stop taking insulin injections for the first time, after their bodies started to produce the hormone naturally again.

In a breakthrough trial, 15 young patients with newly diagnosed type 1 diabetes were given drugs to suppress their immune systems followed by transfusions of stem cells drawn from their own blood.

The results show that insulin-dependent diabetics can be freed from reliance on needles by an injection of their own stem cells. The therapy could signal a revolution in the treatment of the condition, which affects more than 300,000 Britons.

People with type 1 diabetes have to give themselves regular injections to control blood-sugar levels, as their ability to create the hormone naturally is destroyed by an immune disorder.

All but two of the volunteers in the trial, details of which are published today in the Journal of the American Medical Association (JAMA), do not need daily insulin injections up to three years after stopping their treatment regimes.

The findings were released to reporters yesterday as the future of US stem-cell research was being debated in Washington.

Stem cells are immature, unprogrammed cells that have the ability to grow into different kinds of tissue and can be sourced from people of all ages.

Previous studies have suggested that stem-cell therapies offer huge potential to treat a variety of diseases such as Alzheimer’s, Parkinson’s and motor neuron disease. A study by British scientists in November also reported that stem-cell injections could repair organ damage in heart attack victims.

But research using the most versatile kind of stem cells — those acquired from human embryos — is currently opposed by powerful critics, including President Bush.

The JAMA study provides the first clinical evidence for the efficacy of stem cells in type 1 diabetes. Sufferers of the chronic condition, which normally emerges in childhood or early adulthood, have to inject themselves at least four times a day.

Type 2 diabetes, which tends to affect people later in life, is linked to lifestyle factors such as obesity. There are almost two million type 2 diabetics in Briton, most of whom control their blood-sugar levels with pills or through diet.

The new study, by a joint team of Brazilian and American scientists, found that one of the first patients to undergo the procedure has not used any supplemental synthetic

insulin for three years. “Very encouraging results were obtained in a small number of patients with early-onset disease,” the authors, led by Julio Voltarelli, from the University of São Paulo in Ribeirão Preto, Brazil. write. “Ninety-three per cent of patients achieved different periods of insulin independence and treatment-related toxicity was low, with no mortality.”

Type 1 diabetes occurs when the body’s own immune system malfunctions and destroys the insulin-producing beta cells of the pancreas, causing a shortage in the hormone.

By the time most patients receive a clinical diagnosis, 60 to 80 per cent of their beta cells have been wiped out. The disease progresses from this point very quickly, and can result in serious long-term complications including blindness, kidney failure, heart disease and stroke.

Dr Voltarelli’s team hoped that if they intervened early enough they could wipe out and then rebuild the body’s immune system by using stem cells, preverving a reservoir of beta cells and allowing them to to regenerate.

They enrolled Brazilian diabetics aged between 14 and 31 who had been diagnosed within the previous six weeks. After stem cells had been harvested from their blood, they then underwent a mild form of chemotherapy to eliminate the white blood cells causing damage to the pancreas. They were then given transfusions of their own stem cells to help rebuild their immune systems.

Richard Burt, a co-author of the study from Northwestern University’s Feinberg School of Medicine in Chicago, said that 14 of the 15 patients were insulin-free for some time following the treatment. Eleven of those were able to dispense with supplemental insulin immediately following the infusion of stem cells and have not had recourse to synthetic insulin since then, he said.

“Two other patients needed some supplemental insulin for 12 and 20 months after the procedure, but eventually both were able to wean themselves from taking daily shots,” he added. One patient went 12 months without shots, but relapsed a year after treatment after suffering a viral infection, and resumed daily insulin injections. Another volunteer was eliminated from the study because of complications. The therapy, known as autologous hematopoietic stem cell transplantation, has already shown benefits to individuals with a range of auto-immune diseases such as rheumatoid arthritis, Crohn’s disease and lupus.

There are still question marks about exactly how the treatment works, and further studies will be required to fully evaluate it’s safety and efficacy.

“As a research scientist I am always hesitant to speak of a cure, but the initial results have been good and show the importance of conducting more trials,” Dr Burt said.

Given the right funding opportunities, university hospitals in London could be conducting research into the therapy within the next 12 months, he added.

“It will probably be five to eight years before we see a treatment being widely available,” he said.

In an accompanying editorial in JAMA, Dr Jay Skyler, of the Diabetes Research Institute at the University of Miami, wrote: “Research in this field is likely to explode in the next few years and should include randomised controlled trials, as well as mechanistic studies."