Thursday, July 8, 1999 Published at 19:50 GMT 20:50 UK
Protein breakthrough could slow sight loss
Research could help many diabetics with eye disease
A protein found in healthy eyes may hold the key to preventing many people losing their sight in the future, say researchers.
Writing in the journal "Science", doctors described how a protein, pigment epithelium-derived factor (PEDF), halts the growth of blood vessels in areas where they could obscure vision.
This excessive blood vessel growth is a mark of two of the major causes of blindness, diabetic eye disease and macular degeneration.
Blood in the wrong place
The researchers, from Northwestern University in the US, suggest that restoring and maintaining the correct level of PEDF in diabetic patients whose vision is deteriorating might prevent new vessels from growing and leaking blood in the wrong areas.
A spokesman for Moorfields Eye Hospital, one of the UK's top centres, said that this and other innovations meant that research into blindness was entering an "exciting new era".
He said: "Everyone is very excited that there might be potential for controlling the growth of blood vessels.
"There has been a colossal race to find ways of halting their growth."
The research could also tackle a cancer of the eye called retinoblastoma, said Dr Noel Bouck, from Northwestern.
He said: "PEDF may have a double-barrelled effect against retinoblastomas."
He said it could both stop the growth of the blood vessels needed to feed the tumour growth, and also bind directly to the tumour cells themselves, causing them to divide more slowly.
In laboratory tests, PEDF was found to be one of the most potent ways of halting blood vessel growth yet discovered by scientists.