Irish project investigates stem cells for loss of vision

Tue, Oct 7, 2008, 01:00

IRISH RESEARCHERS are investigating the therapeutic potential of adult stem cells in combating the loss of vision in common diseases such as age-related macular degeneration (AMD).

The collaboration between the Regenerative Medicine Institute (REMEDI) at NUI Galway and Dr David Kent, consultant ophthalmologist at the Aut Even Private Hospital, Kilkenny, will involve using stem cells to try to regenerate retinal cells in the macula area of the eye.

Avril Daly, head of public affairs at Fighting Blindness, said AMD was the leading cause of vision loss in the over-50s and it was estimated that the condition affected more than 60,000 adults in Ireland.

“The WHO has stated that the instances of AMD will triple in the next 25 years as our population ages. However, there is currently no cure for the condition and awareness remains low,” she said.

Prof Frank Barry, scientific director of REMEDI, said the organisation was examining developing novel strategies for treating human disease using the stem cell and gene therapy technologies it had developed.

REMEDI PhD student Amy Lynch is investigating the therapeutic potential of adult stem cells in a particular mouse that is very susceptible to macular degeneration. Her work is being supported with strong clinical and scientific guidance from both Dr Kent and Prof Barry.

“We will be taking a very simple first step by delivering the stem cells directly into the retina. We will look at different kinds of adult stem cells and maybe use a combination of stem cells to see if they repair or reverse macular degeneration,” said Dr Barry.

He said this research project was very important because of the high incidence of AMD in Ireland and worldwide.

“We are delighted to initiate the project in collaboration with Dr Kent and will benefit greatly from his clinical and research expertise in AMD. We also welcome the input from Fighting Blindness and the NCBI [National Council for the Blind in Ireland], both of whom have done a great deal to promote the research effort in Ireland in diseases of the eye,” he said.

David Kent is recognised internationally for his contribution to research in the field of macular degeneration both in the US and Britain. He is pioneering the idea of allowing the macula to heal and repair itself without causing vision loss.

He said the macula was located in the centre of the retina at the back of the eye. Ageing changes can occur in the macula and AMD occurs when these changes interfere with vision.

The first treatment for AMD was prevention, said Dr Kent, who pointed out that smokers were six to eight times more likely to develop the condition than non-smokers. He also recommends a diet rich in antioxidants and Omega-3 fats to prevent AMD as well as regular vision check-ups. The current treatments for AMD include thermal laser, photodynamic therapy and new drugs that prevent the growth of abnormal blood vessels in the macula.

Onset of the condition can occur as early as the age of 50 and AMD affects to some degree 35-50 per cent of people over the age of 75. Symptoms to be aware of include painless loss of vision or distortion of vision.

There are two types of AMD – dry and wet. All cases start as dry but many progress to wet as abnormal blood vessels grow beneath the macula. Dry AMD causes gradual loss of vision, while wet AMD can lead to rapid loss of sight. There is currently no cure for AMD but significant progress has been made in the treatment of wet AMD.