This is a ‘Don’t jump to conclusions story.’ Scientists working with the RIKEN Center for Developmental Biology (Kobe, Japan) and published in the journal Nature, 6 April 2011, Paywall [Self-organizing optic-cup morphogenesis in three-dimensional culture], an article complete with photobook of 3D imaging at a glance, have announced that mouse embryonic stem cells have been induced to grow a retina-like structure. Let’s parse that last statement: The embryonic stem cells come from mice, meaning that from mice to man will be a long transition, at best. What was induced to grow (using techniques of synthetic biology) was retina-like, meaning that the formation resembled the light sensitive organ of eyes (the retina) in both cellular structure and shape (cup like). The ‘like’ part has to be added because the researchers did not test whether these cells were actually sensitive to light (photosensitive) or could be hooked up to other visual neurons. So what they did is create a very interesting tissue culture, pointing in the direction of growing replacement elements for eyes.
This tissue is a long way from an ‘embryonic eye’ or even from a successful transplant material. Of course, the researchers weren’t expecting to make working eyeballs. The key to this result of synthetic biology is not that the ‘embryonic eye’ is ready for use in transplants or that the technique be immediately applied to regenerating cells in eyes. Those things may happen, but they are far down the road of research, animal trials and human clinical trials. What’s more immediately important is that the technique and resulting tissue can be used to test drugs and other research assumptions about how the retina is formed and how it is affected by disease.
The research achievement was to get these embryonic cells to work together to form three-dimensional structure and the layering features of normal retinas. The techniques involved have application to other types of stem cells and are part of a very broad research effort to produce viable synthetic tissue.
For a more detailed description, try the ever succinct review of the findings at Your health, your choices from Britain’s National Health Service:
However, even if these laboratory-grown retinas are not eventually usable in transplants, the ability to grow retina-like structures in the laboratory should help scientists to understand more about how the retina develops and how it is affected by disease. They may also be useful for testing the effects of various drugs on the retina in the laboratory. Overall, this appears to be an important step forward for retinal research.