Stem cell research in Southampton offers further hope for AMD sufferers

Professor Andrew Lotery

There is hope for visually impaired patients around the world thanks to leading edge research being carried out in Southampton.

Professor Andrew Lotery, consultant ophthalmologist at Southampton Eye Unit, and his lab team at the Vision Research Unit are currently developing therapies that could eventually restore sight in age related macular degeneration (AMD) patients.

AMD, which can be either ‘wet’ or ‘dry’, is the most common cause of blindness in the western world and occurs when the cells of the macula become damaged and stop working – the condition affects one in three elderly people by the age of 75.

Wet macular degeneration is the most severe form, as unhealthy new blood vessels can grow rapidly into the retina but bleed because they are fragile, causing scarring and permanent loss of vision.

However, treatment with a new class of drugs called anti-VEGF agents can halt these blood vessels and prevent further damage.

Anti-VEGF drugs have been available at the Eye Unit, which is based at Southampton General Hospital, since February 2008 and around 90 per cent of patients see stabilisation of vision and 30 per cent see their vision recover.

But it is dry AMD, the most common form of the disease, that is causing a headache for ophthalmologists around the world. At present there is no cure or reliable treatment.

Now, though, Professor Lotery’s research team are in the early stages of several projects that could change all of this.

One of these involves using tissue retrieved from patients undergoing corneal surgery at the Eye Unit. The team hope to isolate stem cells from this tissue, reprogramme it and transform it into retinal cells. These will then be grown on synthetic polymers (plastic) and inserted back into the eye.

It is envisaged the cells will then merge with the retina or the retinal pigment epithelium and repair or replace lost or damaged photoreceptors.

The synthetic polymer (plastic), due to its biodegradable nature, would give the cells support initially and then just break down so that nothing foreign remains within the eye.

Professor Lotery, who is also a professor of ophthalmology at the University of Southampton, said: “We have made major progress into AMD discovery and treatment in Southampton over the past decade, but we are working hard to go much further and find new treatments to beat blindness.

“This latest stage of our research is just one part of the cutting edge work we are carrying out, but it is only possible to try these new ideas due to the results we have already achieved here in the lab.”

Last year, the lab team identified a major new genetic association with AMD. The gene, named SERPING1, is faulty in up to 25 per cent of sufferers.

During a recent public lecture entitled Beating Blindness, Professor Lotery indicated just how far things have advanced in the field of AMD research since he received his first grant award in 1992.

“In the space of 17 years, the world view on AMD has changed. The belief that AMD is not genetic and is a disease confined just to the eye has gone and people now realise AMD is strongly genetic and in many cases is a systemic disorder,” he said.

Genetic progress since 2002 has led to an understanding of the molecular basis of AMD. New insights into genetics of glaucoma, retinitis pigmentosa and other inherited disorders mean genetic mutations can now be found in up to 90 per cent of AMD patients.

Professor Lotery believes the next ten years will see treatment based on a patient’s genetic background, longer lasting treatments for macular degeneration and diabetic retinopathy and, quite possibly, stem cell therapy.

However, the biggest challenge facing Professor Lotery’s team is a lack of funding.

“Although ophthalmologists provide 10 per cent of all NHS outpatient work, we are under-represented in grant allocations and receive less than one per cent of Medical Research Council funding,” he said.

The Vision Research Unit needs to secure £2.5 million in funding over the next five years and will rely heavily on the charity the Gift of Sight Appeal (www.giftofsight.org.uk) which was established in 2004 to raise money for the research.

Professor Lotery added: “We have made real progress and can continue to make huge strides over the next few years, but we cannot stress enough how vital donations to the Gift of Sight Appeal are in order for us to develop. All donations or legacies really make a difference. The work is at a vital stage now and it can’t be allowed to fail due to lack of funding.”

Posted on Friday 12 June 2009