Eyes and Stem Cells
Eyes and Stem Cells
Two and a half years ago, Edward Bailey had a stem cell transplant to his left eye, which had been blinded in an industrial accident in 1993. His vision in the left eye is blurry, but he is able to see colors and shapes. Mr. Bailey told his story earlier this year on CNN. The operation that Edward Bailey had was one of several in Britain that involved taking naturally occurring limbal stem cells from donors’ eyes, growing them in culture, and then transplanting them into the patient. According to The Times, the doctors were “astonished at how the cells appeared to trigger the eye’s natural regeneration of its damaged surface.” There was no rejection issue, either. In these cases, the patients had all lost sight due to corneal injury, not to retinal damage. Similar work has been done at the Medical College of Wisconsin since at least 2001.
How common is this story? We hear about stem cells being used in trials for heart conditions and leukemia, and earlier this month I reported that they are being used in deafness. What’s the standing with stem cells and vision?
Over a year ago, Dr. Robert Lanza’s team at Advanced Cell Technology in Massachusetts was able to make embryonic stem cells differentiate into retinal cells. Lanza was quoted in the MSNBC story on this as saying, “They looked like little eyeballs. These things seem to be trying to assemble into primitive eyes.” Although the researchers were only clearly able to identify retinal cells, some of the cells resembled those that generate rods and cones. Lanza worked from cells which were not federally approved, and so was able to avoid the issue of contaminated lines; potentially, his cells could be transplanted into a human. He said that using cloning technology would ensure a genetic match and avoid rejection issues. The study was also reported by Wired News, and Lanza was quoted in that article as saying, “Embryonic stem cells like to do what they want to do, and one of the things they like to do is make neurons. They tend to be much easier to derive.” Retinal cells are actually a type of neuron. The Wired News article concluded,
Previous research has shown limited success in transplanting retinal cells derived from fetal or adult stem cells. Lanza and his colleagues are confident that their embryo-derived cells will work even better, because the cells are even more similar to natural retinal cells than those that were tested previously.
I checked the Advanced Cell Technology website and there are no press releases or published papers with any follow-up to this research, so I can’t tell you the current status of Lanza’s work in this area. In another study that was published in the journal Stem Cells on August 25, 2005, researchers from the University of Missouri demonstrated that embryonic stem cells transplanted into mice helped prevent retinal degeneration.
In 2004, researchers at Harvard's Schepens Eye Research Institute transplanted retinal stem cells from the eyes of healthy mice into mice who had retinal disease. After several weeks the transplanted cells had migrated into the damaged areas of the eyes and appeared to have become normal cells. (This study is reported on EurekAlert.)
The International Society for Stem Cell Research has a page devoted to the status of stem cell research on eyes.
It appears that for people with corneal injury, the potential for regaining sight through a limbal stem cell transplant is increasing. Stem cell treatment for retinal degeneration, disease, or injury is still a long way from actuality.
9 Comments:
My husband was blinded after an auto accident and a head injury. His optical nevers are damaged. We need information on this field of opticle nerve aporothy and if there is research into correcting this process through stem cell research?
optical nerve damage that resulted in being blind, from a auto accident in may. Any information on this would help.
There doesn't appear to be much going on other than what I reported in the original post. The use of stem cells in treating neural damage is still very much in the earliest stages. One source I did find is on glaucoma and other optic nerve disease or injury:
http://www.glaucoma.org/research/optic_nerve_and.html.
Stem cells have been shown to move to the retinal area, but it is not yet known if sight is actually restored in an animl model. At the present, optic nerve regeneration is still not possible.
An article by Larry Benowitz on the same glaucoma site (http://www.glaucoma.org/research/optic_nerve_reg_1.html) says
"Is there any way that damage to the optic nerve can be reversed?
"At the present time, no. Research is still in the initial stages of investigating the mechanisms of regeneration and how they can be stimulated. However, there is a lot of exciting work going on in this area.
"Optic nerve regeneration is possible in some lower vertebrates. For example, in animals such as fish and frogs, an injured optic nerve regenerates fully, allowing for a complete restoration of vision. In mammals, it has been shown that retinal ganglion cells, when put under conditions found in the peripheral nervous system, can successfully regenerate their axons. Researchers are studying the visual systems of these animals to find out what factors stimulate retinal ganglion cells to regrow their axons and restore the transmission of visual information to the brain.
"This is only one piece of the puzzle, however. An important consideration in glaucoma is the health of the retinal ganglion cells during the course of the disease. Unlike cells in most other tissues, we have a fixed number of retinal ganglion cells that must last a lifetime. Once they die, they cannot be replaced."
My optic nerve, lots of broken bones and head was injured in March in an automobile accident. I am now blinded in my right eye from that accident but I hold out hope for stem cells. Are there any biological setbacks from taking stem cells from my one UNDAMAGED eye??
You posted my question in your blog. I just wanted to say thanks!
my sons optic nerves were both damaged after surgery to remove a tumor but he had a hemarage,also he cannot walk due to damage to his cellbellum,is there any research to help him,all this happened in 2000.
my sons optic nerves were both damaged after surgery to remove a tumor but he had a hemarage,also he cannot walk due to damage to his cellbellum,is there any research to help him,all this happened in 2000.
My nephew, nearly 2, was born with an underdeveloped optical nerve. Any information on this would be helpful, could stem cell research be an option to help him to see?
In Jan. of 2006 I was a victim of a drive-by shooting. I was walking out of a restaurant and was shot in the face with a 9mm. The doctors told me that the blunt force impact of the bullet damaged my optic nerve. I have not been told what the exact damage is. I have been told along with the damaged optic nerve my retina was scared. I saw a doctor in California at UCSF and he told me it would be about 10 to 20 years before anything could be done with my optic nerve. I would love to know if there is anything or anyone who could help me? I will be a lab rat. I am being told that there are risks involved in any surgey. This I know, but with my case I cannot see out of the eye as it is. So I do not see the risks.
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