A controversial stem cell treatment tested in Brazil has freed patients with type-1 diabetes from dependence on insulin. Since the treatment some patients have been able to stop from injecting the drug for years.
"It's the first time treatment has made patients insulin-free, although I never say it's a cure," says the co-leader of the team, Richard Burt of Northwestern University Feinberg School of Medicine in Chicago, Illinois. "Some patients relapsed and had to go back to using insulin, but even if they did, they didn't require as much as they did before the treatment."
The treatment is designed to stop the immune systems of patients with type-1 diabetes from mistakenly destroying the pancreatic islet cells which manufacture insulin, the hormone that keeps blood sugar levels in check.
Spectacular preliminary results from the trial in 2007 were dismissed by some critics who claimed the outcomes may have been down to immunosuppressive drugs used in the treatment regime, or simply due to better care of the patients because they were in a clinical trial.
Islet recovery But the latest results, which include updates on the original 15 patients and data from a further eight, suggest the treatment may indeed work as proposed. Demonstrating that most patients had elevated blood concentrations of C-peptide, a breakdown product of insulin production, Burt says is a clear sign that the patients were making insulin themselves.
Developed mainly by Burt's colleague Júlio Voltarelli of the Regional Blood Center in Ribeirão Preto, Brazil, the treatment relies on extracting and storing CD34 stem cells from the blood of patients. These stem cells can grow into all white blood cells of the immune system.