Scientists use light-sensing protein to restore vision - Daily Mail

Key to the process is a light sensing protein called MCO1 opsin, which restores vision when attached to specific cells at the back of the eye. .

These so-called bipolar cells, which remain intact in people with common eye diseases, are part of the sensory pathways for light perception and vision.  .

The firm's newly developed light-sensing protein restores vision in blind mice when attached to retina bipolar?

Retinitis pigmentosa (RP) is a group of rare, genetic disorders that involve a breakdown and loss of cells in the retina - the light sensitive tissue that lines the back of the eye. .

These genes carry the instructions for making proteins that are needed in cells within the retina, called photoreceptors. .

'A clinical study in people will help us understand how signalling through bipolar cells affects vision quality,' said study author Subrata Batabyal at Texas-based firm Nanoscope. .

'If this optogenetic approach using cells spared in degenerated retina can prove to be effective in vision restoration in humans, beyond light perception, it could offer a valuable alternative to the retinal prosthesis approach for people with late-stage retinitis pigmentosa,' said PaekGyu Lee at the National Institutes of Health, which funded the project. 

A variety of common eye diseases including age-related macular degeneration and RP damage the photoreceptors – the cells in the retina that respond to light – which impairs vision. 

In the retina, bipolar cells exist between photoreceptors and ganglion cells. 

Bipolar cells are the only nerve cells that connect the outer retina to the inner retina. 

But while the photoreceptors may no longer fully function, other retinal neurons, including a class of cells called bipolar cells, remain intact. 

The investigators identified a way for bipolar cells to take on some of the work of damaged photoreceptors.  

The human gene is the virus then causes retina cells to produce a light-sensing protein called MCO1 opsin.   

MCO1 opsin restores vision when attached to retina bipolar cells by allowing bipolar cells to take on some of the work of damaged photoreceptors

'Bipolar cells are downstream from the photoreceptors, so when the MCO1 opsin gene is added to bipolar cells in a retina with non-functioning photoreceptors, light sensitivity is restored,' said Samarendra Mohanty at Nanoscope. 

When activated by light, the photoreceptors pulse and send a signal through other retinal neurons, the optic nerve, and on to neurons in the brain. 

Other opsin replacement therapies require the intensification of light in order to reach the threshold required for cells to process light, but intense light risks further damage to the retina.