A pioneering stem cell treatment is restoring sight to patients who had given up hope of their eyes recovering from chemical accidents or disease, the surgeon behind the procedure said yesterday.

Sheraz Daya and his team from the Centre for Sight have treated more than 20 people, many of whom had failed corneal transplants, by growing cells, mainly from dead donors, in the laboratory and then transplanting them on to the patients' eyes.

The technique, which builds on research in Italy and the US, could also encourage those who hope stem cell therapies will reduce the need for transplants of organs such as the heart and liver.

DNA analysis of the eyes of some of Mr Daya's patients, months after the transfer, has suggested that donor stem cells have been replaced by the patients' own stem cells.

Edward Bailey, a patient at the Centre for Sight at the Queen Victoria hospital, East Grinstead, Sussex, can remember bathing his once sightless left eye after returning home from his operation in February 2003. "I covered up my good eye and there was me in the mirror. It was very emotional. I'll never forget it."

Mr Bailey, 65, from Selsey, Sussex, had lost the vision in one eye in an accident which happened as he was cleaning equipment at a yoghurt plant in May 1993. A drop of liquid caustic soda caused the damage and two previous corneal transplants and other operations had failed to provide a lasting repair.

But the stem cell treatment followed by another transplant cured him. "By this time I had had a blind eye for 10 years. Previously I had had excellent vision."

Vision in his once-blind eye was a bit blurry but, he said: "I have vision. I wear glasses for reading the paper, doing the crossword, watching telly, and that's it."

The problem for patients like Mr Bailey is the absence or severe shortage of limbal cells. These cells are under the eyelid and protect and help keep clean the surface of the cornea, the transparent front of the eye which has five layers. Without them, a corneal transplant, often a very successful operation, can quickly fail.

But there has been evidence that the stem cell transplants have appeared to trigger the production of new limbal cells - a surprising and encouraging outcome, said Mr Daya. "We think the donor cells have attracted stem cells from the bone marrow to make new limbal stem cells, which have arrived at the eye through the blood stream."

Mr Daya and his colleagues spent five years perfecting the technique. Cells taken from cadavers, and, in one case, from a patient's living father, have been grown on plastic in the laboratory over 10 to 20 days, then transferred to the surface of the eye. They are covered by a biological dressing which disappears within three weeks.

Not every stem cell transfer has worked, says Mr Daya, but most of them have. "Fortunately the numbers of people injured by chemical accident or fire crackers are small and hopefully they will get fewer with more health and safety [rules]. But there is another group of patients born with a deficiency of limbal cells."

He added that a team in Japan recently reported that cells from the mouth might help trigger some response in the eye too.

Much research effort is now being devoted to growing and developing stem cells in ways so that they might kickstart repair of, and regeneration in, organs. Some cardiac researchers believe that the best hope for replicating the heart's action and reducing the threat of rejection may lie in harvesting a patient's own cells from the diseased organ, multiplying them in a laboratory and then putting them back in the patient's body.

Trials involving collecting cells from patients have taken place, and experiments with putting them back may start soon, a team from Baltimore and Rome has suggested.

But if Mr Daya is right, even those who need the therapy of someone else's stem cells to begin with might go on to produce their own stem cells.