New stem cell treatment offers potential cure for blindness

Three people suffering from blindness in one eye have been given a new medical treatment to radically improve their eyesight by a team working at the Australian University of New South Wales. According to the journal Transplantation, the method involves taking 'limbal' stem cells from the patient's healthy eye. They are used to grow into a layer coating a contact lens. The lens is then placed on the patient's damaged eye for approximately two weeks to allow the cells to attach to the cornea. Within weeks there were noticeable improvements, which are still apparent 18 months after the treatment took place.

The patients were all suffering from different forms of corneal disease, which is the fourth most common form of blindness, affecting approximately 10 million people worldwide. It can be caused by surgery, burns, infection or chemotherapy, and is usually treated with transplants or grafts. In this case, two patients had suffered damage to their corneas after surgery for tumours, while the third had a genetic eye condition called aniridia. Two of them were legally blind in one eye but can now read the largest letters on the eye chart visual test. The third was previously able to read some of the chart - after treatment they can now pass the vision test for a driving exam.

Team leader Dr Nick Di Girolamo emphasised that the treatment was cheap and relatively simple to carry out. 'If you're going to be treating these sorts of diseases in Third World countries all you need is the surgeon and a lab for cell culture. You don't need any fancy equipment'.

The researchers are hopeful the technique can be adapted for use in other parts of the eye, such as the retina, and even in other organs.

'If we can do this procedure in the eye, I don't see why it wouldn't work in other major organs such as the skin, which behaves in a very similar way to the cornea', said Dr Di Girolamo.

Research on treatments using stem cells derived from embryos has provoked controversy both in Australia and elsewhere. However, Loane Skene, professor of law at the University of Melbourne and former Deputy Chair of the Lockhart Committee on human cloning and embryo research, said of the current study: 'Provided that patients are told that the new procedure is experimental and possible risks are not yet known, and they then consent to have it, this use of a patient's own stem cells is no more ethically contentious than a skin transplant'.