Recently, the use of the body’s innate regenerative potential has been studied as a treatment option for some ocular diseases.
For example, in cases of corneal blindness, due to the loss or damage of the limbal stem cells at the edge of the cornea, from disease or chemical injury. Recent clinical trials, have used lab cultured limbal stem cells implanted into the diseased areas of the cornea in order to renew it.
Another clinical trial being prepared at our research department (as a member of a Spanish clinical research network) proposes the use of adipose-derived adult stem cells to regenerate the corneal stroma.
The crystalline lens is another potential target for ocular tissue regeneration. Currently, when a patient develops cataracts, the opaque inner part of the lens is surgically removed from the capsular lens bag and replaced with an artificial lens. However, in many cases, some lens cells remain. These cells grow unorganized and produce scar tissue. This process is called posterior capsular opacification. However, we have noticed that certain areas of this "opacification" show normal lens morphology. Based on this, one of our current research projects is to understand how to stimulate the stem cell like activity of these cells to regenerate a complete transparent crystalline lens.
While we still cannot regenerate entire ocular tissues, such as the whole cornea or retina, specific cells are being regenerated from stem cells and inserted into the eye in order to regain specific functions.
Finally, another major cause of blindness is the degeneration of the retina, such as in retinitis pigmentosa. The Centre for Genomic Regulation (CRG) in Barcelona has demonstrated in mice, that retinal cells can be reprogrammed in vivo into retinal precursors that then differentiate into functional photoreceptors, specialized cells devoted to converting light into visual signals. We are currently collaborating with the CRG by preparing retinal tissue from donors to confirm these results in humans.
Ralph Michael and Justin Christopher D'Antin, researchers at the Barraquer Ophthalmology Centre.