• Scientists create an ‘eye-in-a-dish’: Light-sensitive retina produced using stem cells could one day help blind regain their sight

  • Scientists copied processes that occur in the womb to create eye tissue
  • Study used adult stem cells that have been genetically reprogrammed 
  • Lab-grown tissue responded to light the same way as it does in the eye
  • The study represents a first step towards restoring sight in the blind

By ELLIE ZOLFAGHARIFARD
PUBLISHED:  10 June 2014
A light-sensitive ‘eye-in-a-dish’ has been created by scientists using a type of human stem cell.
The three dimensional structure represents a first step towards restoring sight to the blind, say the researchers.
Processes that occur in the womb were copied to create complex retinal tissue in a laboratory petri dish.

 HOW WAS EYE-IN-A-DISH CREATED? 
The experiment was conducted using induced pluripotent stem (iPS) cells, which are adult cells that have been genetically reprogrammed back to embryonic-like state.
Like embryonic stem cells, iPS cells have the potential to develop into virtually any kind of tissue in the body.
The scientists coaxed them to become precursor retinal cells which then developed further into three dimensional bodies.
At a stage equivalent to 28 weeks of foetal development, the scientists tested the mini-retina by exposing it to pulses of light.
They found that the lab-grown photoreceptors responded to light the same way as they do in the human eye.
Human retinas contain two major photoreceptor cell types, rods and cones. Most are rods, which are sensitive to low light.
The petri dish retina was also dominated by rods.

The retina is the layer of photo-sensitive cells and neurons at the back of the eye that converts light signals into nerve messages transmitted to the brain……

Source: Daily Mail

On