Skip to comments.Stem cell therapy shows promise for rescuing deteriorating vision
Posted on 03/30/2007 8:11:53 PM PDT by cryptical
For the millions of Americans whose vision is slowly ebbing due to degenerative diseases of the eye, the lowly neural progenitor cell may be riding to the rescue.
In a study in rats, neural progenitor cells derived from human fetal stem cells have been shown to protect the vision of animals with degenerative eye disease similar to the kinds of diseases that afflict humans. The new study appears today (March 28) in the journal Public Library of Science (PLoS) One.
The lead author of the study, University of Wisconsin-Madison researcher David Gamm, says the cells - formative brain cells that arise in early development - show "some of the best rescue, functionally and anatomically" of any such work to date. In animals whose vision would typically be lost to degenerative retinal disease, the cells were shown to protect vision and the cells in the eye that underpin sight.
The new findings are important because they suggest there may be novel ways to preserve vision in the context of degenerative diseases for which there are now no effective treatments. Macular degeneration, an age-related affliction that gradually destroys central vision, is a scourge of old age, robbing people of the ability to read, recognize faces and live independently.
The finding that the brain cells protected the cells in the eye was a surprise, according to Raymond D. Lund, an author of the new study and an eye disease expert at the University of Utah and the Oregon Health and Sciences University. The neural progenitor cells, which arise from stem cells and further differentiate into different types of cells found in the central nervous system, were being tested for their ability to deliver another agent, a growth factor that has been shown to be effective in treating some types of degenerative disease.
What was surprising, say Gamm and Lund, was that the cells alone demonstrated a remarkable ability to rescue vision.
"On their own, they were able to support retinal cells and keep them alive," says Lund, who has conducted pioneering studies of cell therapy for eye disease. "We didn't expect that at all. We've used a number of different cell types from different sources and these have given us the best results we've ever got."
How the cells act to preserve the deteriorating eye cells remains unknown, says Gamm. Like all cells, neural progenitor cells do many things and secrete many different types of chemicals that may influence the cells around them.
"The idea was to test the cells as a continuous delivery system" to shuttle an agent known as glial cell line-derived neurotrophic factor or GDNF, Lund explains. "It's not a sensible thing to inject the eyes many times over years. The idea was to use the cells as a continuous delivery system, but we found they work quite well on their own."
Lund has experimented with other cell types as therapies for preserving vision. The neural progenitor cells, a cell model developed by Wisconsin stem cell researcher Clive Svendsen, have been used experimentally to deliver the same growth factor in models of Parkinson's disease and Lou Gehrig's disease. Svendsen is also an author of the new PloS One report.
"It seems that the cells in and of themselves are quite neuroprotective," says Gamm. "They don't become retinal cells. They maintain their own identity, but they migrate within the outer and inner retina" where they seem to confer some protection to the light-sensing cells that typically die in the course of degenerative eye disease.
For researchers, the work is intriguing because the progenitor cells come from the brain itself, and not from the part of the nervous system devoted to vision.
"This cell type isn't derived from the retina. It is derived from the brain," says Gamm. "But we're not asking it to become a retina. They survive in the environment of the eye and don't disrupt the local architecture. They seem to live in a symbiotic relation ship" with retinal cells.
Gamm and Lund emphasize that the new work is preliminary, and that much remains to be done before the cells can be tested in humans: "The first thing is to show that something works, which we have done," says Lund. "Now we need to find out why, but this is a good jumping off point. "
Source : University of Wisconsin-Madison
For those wondering about the source of these stem cells, they are in the Wisconsin research program, the source seeking federal funding for embryo derived stem cells. The cells in this program were derived from embryos or fetuses. These are not the 'ethical' stem cells of adult stem cell research.
as it does ...
imagine the progress it could make with funding....
What's to keep you from funding it, 'SubGeniusx'?!? There are no restrictions on private funding for embryonic stem cell research. I don't agree with research that causes human beings to be destroyed, but that's the way the law stands.
Of course, those that devalue the basics of human life never bring up this fact....
It's amazing what can be done with stem cells. The possibilities are exciting. IF only they will use the good stem cells and not from aborted babies.
You do realize that adult and embryonic stem cells have different properties, yes? That embryonic stem cells are pluripotent, and so far adult stem cells have not been found to be pluripotent? Which means adult stem cells are great for certain diseases, but have not been shown to have the same promise for other diseases. Also, my impression is that the stem cells used do not, in fact, come from aborted babies; they come from extra embryos due to be discarded by fertility clinics.
Please tell us that you're just being facetious when you say that aborted babies and 'extra embryos' aren't the same.
No, I'm not. Embryos from fertility clinics may have the same value, but they are clearly not aborted.
Some folks are morally opposed to this and similar endevors, because they consider the embryos to be people. It is wrong to coerce them into involvemnt by using tax money to do it. If the endevor has such wonderful utility, then those that think so should fund it by themselves. They have no justification to force others to do it at gunpoint.
Will the embryos be killed in the removal of their stem cell body parts?
Stem cells aren't body parts.
Prior to a placenta, at the early age of embryo ORGANISM, stem cells are the organs in most potentiated form. As the cascade of stem cells develops specific organs and tissues, the stem cells become lesser parts of the organs but remain vital to sustaining and regeneration throughout life of the ORGANISM.
I agree with cryptical, stem cells aren't body parts. But your response is a side track to what I posted. Blastocysts from fertility clinics are not "aborted."
In both cases, my objection is to using words that mean something quite specific scientifically, and trying to make them mean something else. You can make your argument without that.
I have macular degeneration, but I would not dream of using embryonic stem cells.
Actually, blastocyst is a stage or age that huamns go through in their lifetime begun at conception ... kind of like saying that fetus, or that toddler, or that prepubescent. Each age is a hallmarked mass of cells with varying functionality, but we assume ORGANISM for each of those ages yet dehumanize for the earlier ones.
Abortion traditionally refers to the termination of a pregnancy. Would you feel better if I used the term 'life termination' in order to get the cell parts of the embryo for research exploitation? Do you consider an embryo to be a human at earliest age?
"I have macular degeneration, but I would not dream of using embryonic stem cells"
I'd rather learn braille than cause embryos to be sacrificed for my sight.
WHAT ABOUT TYPE 1 DIABETES????????
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