A team of Japanese scientists has managed to create stem cells
that re-enact the early stages of mammalian eye development in a
culture dish. The exciting bit is that this includes a
particularly important part of eye development: retina
formation. The team’s work and findings, published in the
journal Nature, could help provide methods for treating
blindness. The retina is a thin piece of tissue at the back of
the eye. It is responsible for converting light, which has
passed through the lens, into electrical nerve impulses.
Thousands of these nerve impulses then travel to the brain,
where they are processed to form an image. Critical to this
activity are the retina's photoreceptor cells; the loss of these
cells is the main cause of untreatable blindness. Without them,
light that passes into the eye cannot be converted into the
signals required to form an image in the brain. In 2006, a team
of scientists from the UK and USA showed that particular stem
cells, when introduced into damaged retinas of mice, could