SCIENTISTS PRINT NEW EYE CELL THAT COULD TREAT BLINDNESS

Scientists have printed new eye cells for the first time - paving the way to cure some types of blindness in humans.

Their research, which used animal cells to test the concept, is the first step towards producing tissue implants.

British researchers used inkjet printers to print two types of central nervous system cells from the retina of adult rats - ganglion cells and glial cells.

Retinal ganglion cells transmit information from the eye to certain parts of the brain and glial cells provide support and protection for neurons.

The study, by the University of Cambridge, found that printed cells were able to grow normally and can be kept healthy but more tests are needed before human trials can begin.

'The loss of nerve cells in the retina is a feature of many blinding eye diseases,' said Professor Keith Martin and Dr. Barbara Lorber from the university who co-authored the study.

'The retina is an exquisitely organized structure where the precise arrangement of cells in relation to one another is critical for effective visual function.'

They said that the study has shown for the first time that cells derived from the mature central nervous system of the eye, can be printed using a piezoelectric inkjet printer, which uses electrically-charged crystals to deposit materials directly on substrates.

'Although our results are preliminary and much more work is still required, the aim is to develop this technology for use in retinal repair in the future,' they said.

Clara Eaglen of the RNIB, told the BBC: 'The key to this research, once the technology has moved on, will be how much useful vision is restored.

'Even a small bit of sight can make a real difference, for some people it could be the difference between leaving the house on their own or not.'

While it is in its very early stages, 3D printing makes it possible to arrange cells into highly defined patterns and structures that can be used in regenerative medicine.

Researchers used an inkjet printer that pushed the cells out through a tiny nozzle when an electrical pulse was applied.

They also used high speed video technology to take high resolution footage of the process.

It is the first time the technology has successfully allowed scientists to print mature central nervous system cells.

'The ability to arrange cells into highly defined patterns and structures has recently elevated the use of 3D printing in the biomedical sciences to create cell-based structures for use in regenerative medicine,' the researchers said.

However, 3D printing of cells can present challenges.

Dr Wen-Kai Hsiao, a researcher at Cambridge, said: 'In order for a fluid to print well from an inkjet print head, its properties, such as viscosity and surface tension, need to conform to a fairly narrow range of values. Adding cells to the fluid complicates its properties significantly.'

The scientists plan on attempting to print other types of retinal cells, such as rods and cones, which handle vision in low light and changes in shape, plus colour and detail.

Professor Martin said: 'We plan to extend this study to print other cells of the retina and to investigate if light-sensitive photoreceptors can be successfully printed using inkjet technology.

'In addition, we would like to further develop our printing process to be suitable for commercial, multi-nozzle print heads.