Research brings hope of restoring eye-sight for blind
Millions of people over the world are blind due to diseases or damage to the retina. One way of repairing the retina and thereby vision could be to use the eye’s own stem-cell-like cells. At Uppsala University’s Department of Neuroscience doctoral student Henrik Ring has studied factors that improve our understanding of how specific cells can be produced from immature retina cells.
One way of repairing a damaged retina is to replace damaged or dead cells using the eye’s own immature stem-cell-like cells. Knowledge about how these stem-cell-like cells divide and produce new specific retina cells is necessary for such a replacement to be successful.
Henrik Ring has in his thesis focused on finding and categorising factors that regulate cell division and cell specification in immature retina cells, to contribute knowledge of how the immature cells can be used to repair a damaged retina.
The most important finding of the thesis is that gamma-Aminobutyric acid, or GABA, supports cell division in the immature retina cells. The cells’ calcium levels are affected by GABA and a suppression of GABA causes low levels of calcium in the cells, which inhibits cell division.
The thesis also shows that the stem-cell-like Müller cells in the retina can be divided into two groups based on expression of a gene called Pax2. What is interesting is that these two groups may have different capacities of repairing the retina since Pax2 seems to inhibit Müller cells becoming nerve cells and instead retains them as Müller cells.
Finally the thesis describes that expression of another gene, FoxN4, leads to cell specification of immature retina cells. By over-expressing FoxN4 in the developed retina the immature cells were transformed into specific retina cells.
‘Our results increase understanding and thereby the possibility of creating specific cells from immature retina cells. We show that different sources of the immature retina cells have different potential to divide and we have identified several important factors for when you want to amplify and get more immature retina cells’, says Henrik Ring.'
The title of the thesis is “Characterization of retinal progenitor cells. Focus on proliferation and the GABAA receptor system”. The thesis is defended Thursday 13 december.
Cecilia Yates