Diabetics have been treated with stem-cell therapy for the first time, freeing them from the need to have regular insulin injections.

The results of the small trial in which 15 newly diagnosed young patients with type 1 diabetes were treated with their own stem cells could mark the start of a revolution in tackling the auto-immune disease.

According to a study published yesterday, research-ers gave the patients powerful drugs to suppress their immune systems, followed by transfusions of stem cells drawn from their own blood.

All type 1 diabetics have to self-administer regular insulin injections to control their blood-sugar levels. But after treatment, 14 of the trial patients lost their insulin dependence and were able to put away their injection pens.

Some patients reacting more quickly than others. Over a follow-up period of between seven months and three years, one patient became insulin injection-free for 35 months, four for at least 21 months and seven for at least six months. Two patients who responded late did not have to inject themselves for one and five months respectively.

The findings, published in the Journal of the American Medical Association (Jama), are said to provide the first clinical evidence type 1 diabetics can benefit from stem-cell therapy.

The US and Brazilian scientists, led by Dr Julio Voltarelli, from the University of Sao Paulo, wrote: "Very encouraging results were obtained in a small number of patients with early-onset disease.

"Ninety-three per cent of patients achieved different periods of insulin independence and treatment-related toxicity was low, with no mortality."

There are 2.2 million people diagnosed with diabetes in the UK. It is believed there are also up to 750,000 who have the condition but are unaware of it.

Type 1 is a rare condition which develops in childhood but type 2 diabetes, which accounts for almost 90% of cases, usually occurs in over- 35s and normally in people who are overweight.

Previous studies suggested stem-cell therapy might be a promising approach for type 1 diabetes. Stem cells are immature, unprogrammed cells that can follow different functional paths.

Earlier this month, scientists reported that a patient had suffered fewer low blood-sugar attacks after having pig cells inserted into his stomach 10 years ago.

The insulin-producing cells, wrapped in a seaweed gel, helped control the blood-glucose levels and were producing insulin a decade later, according to a study in New Scientist.

In the case of type 1 diabetes, it is thought stem cells from the blood may generate new immune system cells that avoid attacking the pancreas.

The disease is caused by insulin-producing pancreatic beta cells being destroyed by the patient's own immune system. By the time a person with type 1 diabetes is diagnosed, up to 80% of his or her beta cells have already been wiped out. The disease progresses from this point very quickly.

A chief aim of experimental new treatments for type 1 diabetes is to salvage what remains of a patient's beta cells.

Suppressing the immune system is one answer but, over long periods, the patient's health can be put at risk.

An early clue that stem cells could be a way forward came when bone-marrow transplants given to patients with cancer appeared to reverse auto-immune diseases. Several cases were reported, including one involving type 1 diabetes.

The phenomenon could be explained by the fact immune system white blood cells arise from stem cells in the bone marrow.

Animal studies supported the idea. Later, it was found that an approach called autologous hematopoietic stem-cell transplantation (AHSCT), which involved treatment with a patient's own blood stem cells, may benefit individuals with a range of auto-immune diseases such as rheumatoid arthritis and Crohn's.