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Diabetes "Cured" In Mice With Virus Therapy
phlack writes "Scientists at Baylor College of Medicine have found a way to treat diabetes in mice by using a virus (with the harmful genes removed) to trick the liver into working as a pancreas. This is still a ways away from working in humans, but it's progress, at least. Info can be found at Guardian and Science Daily."
FYI - The real question about this, and other gene therapy experiments, focueses on the safety of the vector being used. In this case an adenovirus virus was used. The virus itself is no longer virulent, but how does the target genetic material get integrated into the hosts genome? If it occurs at a specific site, then safety is maximized. If it occurs randomly, then you run the risk of knocking out genes where only a single healthy allele exists (loss of heterozygosity) and potentially, cancer.
Gene therapy holds a lot of promise, but the early cases of leukemia (remember the bubble boy cure? Two 'cured' patients subsequently developed cancer) make it prohibative. I'm an expert enough to know this a problem (in theory and in practice) but not enough of one to know how close we are to solving it.
-Sean
Up to 2/3 of your liver may be destroyed (or poisoned) and it will still function correctly. I very much doubt that anything like this much will be affected by this process. Therefore it is safe to assume that there will be no percieved effects of this treatment other than the positive!
I suspect that, once you have a way to make new insulin-producing cells, the autoimmune problem will be relatively easy to get around. Prior to this point there was no way to test any potential solutions simply because the problem has never been detected in people until it was too late and their islets were destroyed.
Current immunosuppressive drugs may do well to inhibit the destruction of the new glands. Then again, the "pseudo-islets" may not even express the same antigens as the natural islets of Langerhans, and therefore might be immune to destruction.
This sort of advance should work very well for people who have type I diabetes, where their bodies no long secrete insulin. I have to wonder how well it will work in people with adult-onset, type II diabetes, which is triggered by a malformed receptor that isn't sensitive enough to secreted insulin. The use of oral or injectable insulin might be eliminate, but I worry that the attendant physical ailments, such as diabetic retinopathy, will still dog those who suffer. Unfortunately, the problem of fixing those receptors may prove to be much more difficult.
Ah, no, not easy.
In tests where people have received new insulin-producing cells (either separately, or as part of an entire liver/pancreas transplant) immuno-suppressive drugs are indeed used. In some cases those drug prove effective, but in others the immune-system again destroys the new cells.
Other research has been successful in the 'mice' stage, providing new beta cells wrapped in a miniature shell, with openings wide enough for the insulin to get out, but not wide enough for T-cells to get in, thus providing protection from the immune system. No human tests, yet, though. (I'm sorry to say... as a diabetic, I'd be ready to participate in that kind of research.)
But as you say, this new line is at least an interesting new (for me) approach, and the new islets might be different enough for the immune system to ignore them.
You have to remember that a transplant of islet cells suffers from a double-whammy; not only are they of a cell type that the immune system previously destroyed, but they're also foreign organisms, coming from another human being. It'd be difficult to predict how much better immunosuppressants might work on cells that weren't foreign but merely altered.
Still, being a diabetic myself, I would take anything that got me off the regimen of thrice-daily shots and the constant mood swings.
...listen if I have to take antirejection drugs instead of the crap I have to do now, i'm on board.
Also the threat of longterm vision loss, kidney failure, neuropathy and potential loss of limbs
Hope it's available before my checkout date.
HBI's Law: Frequency of calling others Nazis is directly correlated with the likelihood of the accuser being Communist.
Here is an excellent read on type one diabetes and stem cell research, and a comment on why study sjogren's in conjunction with diabetes (namely, the organ being damaged is much easier to get at and assess.)
Here is a great site for info- the CDC genomics site, which includes info on common and rare genetic diseases, and can give a greater array of background info. NCBI offers another set of info- an explanation of human mouse homology (thus answering the question... why mice?
I hope this helps put some extra info out there for those of you who are interested. And frankly, as one who has had to deal with the sudden "switching on" of not just one but a whole array of diseases- since my DNA happened to include the lucky strands- I'm now having my stance on animal testing completely revised...
"I'd say 'Have a good time,' but arson is still illegal.