*MS Article-Protein Found To Help Optic Neurits*

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http://www.guardian.co.uk/science/story/0,,1774752,00.html

Discovered by chance: protein that repairs optic nerve

Ian Sample, science correspondent

Monday May 15, 2006

The Guardian

Neuroscientists have succeeded in repairing damage to optic nerves

using a

newly identified protein that encourages injured nerve fibres to

regenerate.

The chance discovery will boost hopes of a future treatment to reverse

blindness

caused by injuries to the optic nerve from accidents, tumours or

common eye

conditions such as glaucoma. The researchers hope it will also help the

development of therapies for other debilitating conditions, such as

stroke and

spinal cord injury. The optic nerve is part of the central nervous

system and,

unlike nerves in the peripheral nervous system - such as those in our

fingers

and feet - shows almost no ability to recover from injury. Scientists

believe

the central nervous system has evolved to prevent severed nerves repairing

themselves, as a harsh defence against potentially disastrous rewiring

that

could scramble important signals passing to and from the brain.

Neuroscientists Yuqin Yin and Larry Benowitz at Children's Hospital,

Boston, and Harvard medical school discovered the protein by chance

when they

noticed that injuries to the eye lens caused a chemical knock-on

effect in which

inflammatory cells began churning out molecules to repair the damage.

To see if

they might also help heal damaged nerves, they collected the

inflammatory cells,

grew them in petri dishes and isolated the proteins they secreted.

In lab

tests, Dr Benowitz discovered that treatment with the protein, called

oncomodulin, nearly doubled the growth of optic nerve fibres by

latching on to

them and switching on a suite of growth genes. In further tests, the

researchers treated rats with optic nerve damage and found that tiny

capsules

containing oncomodulin and another drug increased nerve regeneration

by five to

seven times. " Out of the blue, we found a molecule that causes more

nerve

regeneration than anything else ever studied, " said Dr Benowitz, whose

study was

published in the journal Nature Neuroscience yesterday.

He stressed that nerve repair achieved in the rats was only partial

and a

treatment for humans still had significant hurdles to clear. " We

could obtain

pretty dramatic regeneration. With this said, however, there is

another problem

looming, and that is getting the regenerating axons to form

connections with the

proper target cells in a way that preserves the proper mapping of the

visual

space on to the brain. "