Slashdot Mirror
Embryonic Stem Cell Retinal Implants Seem Safe, So Far
An anonymous reader writes "A biotechnology company said Monday that results from the world's first human trial using embryonic stem cells to treat eye diseases suggested that the new procedure appears to be safe four months after the cells were injected into the eyes of two blind patients. The study also describes visual improvements in patients, and experts said the findings hold promise for treating blindness in patients with currently incurable conditions like age-related macular degeneration in older patients and Stargardt's Disease, a main cause of blindness in young people."
The eye is a very complex organ though, so we would be behind. I'm glad to see progress, but even so, 4 months is a little short-term to say "no bad health effects". Given the cells are embryonic stem cells, I'm more concerned with the 10-20 year range.
I have one of the issues listed, and I seriously hope that they can do something about it, I'd prefer a biological rather than mechanical solution, however, four months is not a lot of time, especially when you are messing with something as important as the sense of sight.
Self proclaimed typo king, and inventor of the bear destroying coffee table (patent not pending).
The main reason for this (for those of you who haven't seen a neocognitron in a fourth-year machine learning course) is that the eye does a lot more pre-work for the brain than just blitting a grid of pixels down the optic nerve. Recent efforts attempted to do that, however. There's much more complex pattern recognition going on even at this most basic level, in addition to the loss of precision for the non-focal area, and that helps reduce the cognitive load to something we can fully utilize.
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
[...] I'm glad to see progress [...]
I see what you did there. Oh wait...
var sig = function() { sig(); }
While sight certainly is important, these kinds of treatments are so new that we can't really predict how long we'll actually have to watch before we really know for sure. It could be the case that in another week the new retinal tissue is chemically indistinguishable from what should have been there, or they might already be—that is, after all, the point of this trial, which is really more of an experiment.
Suppositionally, though: given how the vision system develops in human infants, though, I would actually say that three years is probably enough time to be sure one of these treatments was a complete success. When people experience 5-10 year life spans after heart transplants, that's generally because of ancillary factors (replacement heart quality, vessels elsewhere in the body weakened by the same thing that led to the first heart giving out...) and not really the fault of the surgery (well, unless the weak spot is the point of fusion on the vessels.) Rejection happens pretty quick by comparison.
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!
The eye is a very complex organ though, so we would be behind. I'm glad to see progress, but even so, 4 months is a little short-term to say "no bad health effects". Given the cells are embryonic stem cells, I'm more concerned with the 10-20 year range.
I have one of the issues listed, and I seriously hope that they can do something about it, I'd prefer a biological rather than mechanical solution, however, four months is not a lot of time, especially when you are messing with something as important as the sense of sight.
From the actual researchers, they have two major concerns - 1) whether the treatment is permanent and 2) rejection issues. Both are long term concerns like the 10-20 year range you worry about. With regards for the rejection issues, they are quite confident that they will be able to repeat the results using stem cells derived from the patient's skin.
They say they didn't go this route, even though less risky to the patient, because their grant was specifically to use embryonic stem cells in the treatment.
And I am excited about this research, but I would be much more interested in IPS stem cells. You see, my mom is one of those "abortion is bad m'kay?" Types who would oppose getting this treatment on moral grounds if the transplant wasn't cultured from her own tissue.
She scientifically savvy enough to know the difference.
(She does have a biology degree.)
I understand that this is a preliminary trial, but given the information we know about embryonic stem cells and the risks of developing teratomas, cancer and tissue rejection from them, in addition to the ethical concerns, shouldn't the limited supply of embryonic cell lines remain in research labs, and out of patients?
Using totipotent cells cultured from screend ips cells, guided in a petri dish to become macular precursor cells seems a more sensible solution, given that you reduce the risk of anomalous tissue growths (hair, etc...), reduce and or eliminate rejection, and the extended culture time let's you spot cancer precursor cells in the culture prior to transplant.
Or am I missing something here?
It's more profitable to treat the ailment than to cure it? I sure hope they don't pull a 'Geron'. Give them a few more months to solidify their findings ...
Imagination drew in bold strokes, instantly serving hopes and fears, while knowledge advanced by slow increments...
It must have been something you assimilated. . . .
Please, inform yourself. This sort of ignorance is embarrassing. "Harvesting fetuses" is not how we get embryonic stem cells. Excess fertilized embryos are a byproduct of in vitro fertilization. These embryos (not fetuses) would be destroyed if not donated to science. The fertilized embryos are on the order of 50-150 undifferentiated cells -- not a fetus -- in a microscope, one appears to be a spherical blob. At this point, the stem cells are "cultured" -- fed, and allowed to multiply, just like we grow bacteria or other single-celled organisms.
Many of the ethical concerns over embryonic cells would be ended if the collection method was nondestructive.
The problem was hamfisted legislation that treats embryonic blast collection as being equal to murdering babies.
There are single cell extraction techniques which allow cells to be nondestructively collected. This process is used in screening for ivf, prior to embryo selection. (This is how they pick only safe embryos, and not ones likely to produce children with developmental disorders.)
I would rather see legislation prohibiting destructive collection, than against any collection at all.
The issue here, is that we have cells previously collected using the destructive methods prior to the moratorium sitting in freezers, when those tissues could be used for fundamental research.
It is my understanding that demand for these lines is high, as many cultures were co-cultured with mouse tissue for purposes of expediency. This limits the number of "purely human" cultures that are suitale for medical research to a much smaller subset of the already limited cell lines available. (Note, the mouse contaminated lines are not genetically blended. They are just heterogenous.)
What I would personally like to see is an end to the moratorium on federal funding for embryonic cells, with the provision that all NEW lines be derived nondestructively.
Doing that would radically reduce the ethical concerns surrounding their use.
Our ability to create, use, and evaluate adult stemcells is directly tied to the fundamental research done with embryonic ones.
However, I don't support your position on unfettered research. To me that opens far too big of a pandora's box into the realm of public health. Oversight and good proceedure are vital to good research.
The telling question to see where the real issue lies is this one: do you believe a fetus just before birth is a person?
"Drawing a line" is a bit of a straw man. We're talking about hours after conception, not weeks. At this point in time, the cells are indistinguishable from one another. A featureless blob of cells.
I, too, reject the notion that at some magical instant, the embryo becomes a fetus. It's a very gradual process, in the first few hours of which, you've definitely got a lump of undistinguished cells, and 9 months later, you've definitely got a living thing (assuming everything goes ok). There's a lot of grey area, and drawing a line is a vast oversimplification.
Fact of the matter is, we're talking about embryos that are slated for destruction. We're talking about preserving those to save / better future lives. We aren't going around harvesting fetuses.
If an embryo becomes a "person" at conception, then the concept of "person" is severely degraded. With regard to what it can do at conception, a person is then inferior to any animal that doesn't attack human beings and any plant that can be safely eaten or used as a building material. It is only potential that gives an embryo at conception even hypothetical value. If you consider that the embryo might develop into a mass-murderer or a Bernie Madoff, demanding that it be brought to term because it has value as a person is unjustifiable speculation.
Living things act to preserve themselves, and to the extent that they can think they develop an (implicit or explicit) sense of value of their own life. It is from this sense of value that (after many additional considerations) the idea of a right of a person to his own life is developed. A thing without even a trace of a mechanism for thinking cannot be considered to have rights. If a brainless thing without rights is considered a "person", what's the point of the concept "person"?
Contribute to civilization: ari.aynrand.org/donate