News has been released that British scientists are planning to use embryonic stem cells to cure age related macular degeneration, a common form of blindness. They are hoping to have the first patients receive test treatments within five years. This could be a major improvement in the methods of treating this common form of eye blindness that is experienced by millions of individuals throughout the world.
The pioneering project uses cells derived from human embryonic stem cells to repair damaged retinas. Those who support the research believe the process will involve simple surgery that could one day become as routine as cataract operations. Scientists are suggesting that the technique might be capable of restoring vision in patients with age-related macular degeneration (ARMD), a leading cause of blindness among the elderly that afflicts millions of people worldwide and is the leading cause of blindness in the USA and Europe.
If stem cell research can be used to cure age-related macular degeneration, could it also cure keratoconus? In April 2005, doctors in the UK transplanted corneal stem cells from an organ donor to the cornea of a woman who was blinded in one eye when acid was thrown in her eye at a nightclub. The cornea, which is the transparent window of the eye, is a particularly suitable site for transplants. In fact, the first successful human transplant was carried out in 1905 on a cornea by Dr. Eduard Zirm. The cornea has the remarkable property that it does not contain any blood vessels, making it relatively easy to transplant. The majority of corneal transplants carried out today are due to a degenerative disease called keratoconus which causes vision impairment and has no known cure even after corneal transplant. It is hoped that stem cell research will one day provide a cure to such debilitating corneal disorders.
The first step would be to grow corneas from a living donor. The corneas could then be transplanted into the person’s eyes. The advantage to using a patient’s own tissue would be a reduction in the possibility of rejection and a decrease in medications required to suppress a patient’s immune system.
Later steps might involve injection of healthy corneal cells into a keratoconic cornea in order to increase the strength of the cornea tissue. Stem cells could help reinforce the cornea and prevent the loss of vision that accompanies the progression of keratoconus.