PETER CAVE: Medical researchers at the University of New South Wales are claiming success in curing partial blindness by coating contact lenses with stem cells. The patients with diseased corneas wore the lenses coated with their own stem cells and after about a month their corneas had regrown.
The scientists say that in the future the technique may be used to help people blinded by other causes.
Meredith Griffiths reports.
MEREDITH GRIFFITHS: One of the main causes of blindness around the world is diseases affecting the cornea. That's the thin clear barrier at the front of the eye and if it gets diseased, scratched, scarred or burned, light can't make it through to the retina.
The World Health Organization says that every year corneal disease could be responsible for one-and-a-half-million people losing sight in one of their eyes. But now researchers in Sydney have found a way to overcome that for some patients.
Dr Nick Di Girolamo is a medical scientist at the University of New South Wales.
NICK DI GIROLAMO: The cornea is the window to the eye so any abnormal cells that are growing on top of a healthy cornea would preclude or would distort vision.
We've gone from patients that have only been able to count fingers, you know, at a close distance in front of their eye so to speak, to being able to read letters on a standard visual chart.
MEREDITH GRIFFITHS: The three patients in question were legally blind in one eye. The scientists took some stem cells from their healthy eyes and cultured them inside contact lenses for 10 days. The patients then wore the contacts and after less than a month their corneas had regenerated.
Dr Nick Di Girolamo again.
NICK DI GIROLAMO: We can grow the cells on a contact lens, that was the biggest challenge, to make sure that they were healthy and remained stable on that contact lens for a period of time. And then it was just a matter of trusting that they could transfer from the contact lens surface onto the patient's ocular surface.
MEREDITH GRIFFITHS: He says the patients only need to wear the contact lenses for about 10 days and that the beauty of the technique is that it uses the patient's own cells.
NICK DI GIROLAMO: So we're not going to be using any immunosuppressive therapy to prevent rejection if you want; whereas most other techniques out there utilise foreign human materials or stem cells that are grown in the presence of animal products. You know there's a potential risk of foreign infectious agents in that material.
MEREDITH GRIFFITHS: Dr Di Girolamo says the plan now is to grow a whole cornea.
NICK DI GIROLAMO: We're focusing on corneal disease because of the accessibility of the cornea but it's quite possible that using a similar material to the contact lens material, you know in the future that sort of material could be used as a carrier of different stem cells such as retinal stem cells to the back of the eye.
MEREDITH GRIFFITHS: Do you think in years to come this will help people with other problems who are blind for other reasons?
NICK DI GIROLAMO: Oh most definitely. Certainly you know there needs to be a lot more laboratory work looking at this sort of technique for diseases in the back of the eye, like macular degeneration for example.
MEREDITH GRIFFITHS: Jane Ellis from Vision Australia says the study is good news for anybody with corneal problems but she says at the moment the treatment can only help people with damage to the edge of the cornea.
JANE ELLIS: The most common form of corneal problem that we see in Australia is called keratoconus which is where the cornea grows in a very odd shape. The use of stem cells to correct that will be a great breakthrough because currently the treatment is around corneal transplant and as we know, the risks around surgery to the cornea are quite high. The waiting list for corneal transplants is very high.
MEREDITH GRIFFITHS: Jane Ellis says the study illustrates just one of the many possibilities that stem-cell research is opening up for people who are blind or have poor vision.
PETER CAVE: Meredith Griffiths.
Source: The World Today - Thursday, 28 May , 2009
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