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Body's Immune System can be Redirected
Ridgelift writes "BBC News have this story of a key chemical signalling system, called Notch, which governs how our body develops immune cells. By pre-treating patients who are about to undergo an organ transplant, it's possible to 'redirect' the immune system so it does not launch an attack on the donor organ. This may soon eliminate the need for transplant patients having to take a lifetime of powerful immunosuppressive drugs that have many unwanted side-effects."
If so, please email me, as I would certainly prefer being superhuman and taking over the world.
I wonder if this could somehow be adapted to treat Multiple sclerosis, where the immune system attacks its own myelin...
Any thoughts?
immunesystem > /dev/null
Treating a transplant patient in advance of the operation with cells from the donor could reduce the need for powerful drugs afterwards.
The treatment "redirects" the immune system so it does not launch an attack on the donor organ.
Researchers from three UK universities have found a key gene signal that may help protect the new kidney.
The study, published in the Journal of Clinical Investigation, could lead to fewer side-effects for patients.
The number of organs transplanted from live donors is increasing as other supplies of organs diminish.
However, in the absence of a perfect match, patients still have to take high doses of drugs to suppress their immune systems so the organ is not rejected.
Taking such high doses of drugs is counterproductive - they may even increase the chances of cancer in some cases - and scientists are looking for alternative ways to reduce the chance of immune rejection.
The team from Cambridge and Edinburgh universities, and Imperial College London, may have found a way to change the manner in which the body responds to a new organ.
Chemical messages
They have found a key chemical signalling system, called Notch, which appears to govern how immune cells develop.
When they exposed mice to a combination of this signal, and material from the donor-to-be, about two weeks before the actual transplant operation, they generated an immune response.
However, when it came to putting in the new organ, they found that the immune system, rather than attacking it, seemed to have been "educated" to turn a blind eye.
Mice given a heart transplant following such treatment found that the length of time the new organ stayed unmolested by the immune system increased fourfold compared with untreated animals.
The treatment appears to encourage the development of one type of immune cells - T suppressor cells, that put the brakes on any immune response.
It also seems to reduce production of T helper cells, which help drive powerful immune reactions.
Gentle therapy
Professor Maggie Dallman, from Imperial College, was one of the scientists leading the experiments.
She said: "Today, even with extensive efforts to find the best possible immunological match between donor and recipient, organ transplantation consigns the recipient to a lifetime of powerful immunosuppressive drugs that have many unwanted side-effects.
"Increasingly organ transplants, in the case of kidneys, liver or lung tissue occur between living relatives, so you know in advance who the donor and recipient are.
"Our strategy opens up the possibility of offering gentler postoperative therapy by redirecting the recipient's immune system in advance of the transplant."
Health risk
Dr Anthony Warrens, a specialist in renal medicine and immunology at London's Hammersmith Hospital, said that it might be possible to use a variety of methods to reduce the need for immunosuppression drugs in the future.
"We already offer a very good service to transplant patients - we're just looking to make it better."
He said that the problems caused by long-term immunosuppression - cancer, vulnerability to infection and accelerated heart disease, meant that one of the main reasons for transplant "failure" was the death of the patient from other causes, even though the transplanted organ remained in good condition.
Another method being investigated, he said, was giving a "mini" bone marrow transplant prior to the operation to reprogramme the immune system - or even a short course of treatment to the would-be donor which reduces the risk of rejection.
By reading this signature you agree to not disagree with the post you just read.
By pre-treating patients who are about to undergo an organ transplant, it's possible to 'redirect' the immune system so that it does not launch an attack on the donor organ.
A couple of quick points:
1. The experiments were done in mice, not humans.
2. All the mice undergoing the treatment underwent graft rejection.
During the early 80s scientists at the Fred Hutchinson Cancer Research Center experimented with T-cell depleted stem cell transplants in an effort to prevent graft-versus-host disease (GvHD), a principal cause of death following bone marrow transplantation. The principle behind GvHD is similar to that of an organ rejection, except that the immune system recognizes the whole body as foreign and attacks it. When mice were given T-cell depleted transplants from MHC mismatched donors (something that promotes GvHD and is why you have to find a bone marrow donor match), their survival rates were identical to that of mice who receaved autologous transplants (they donated bone marrow to themselves - no GvHD). To say that the transplant community was excited would be an understatement. One prominent scientist even wrote that "we've (the transplant community) solved the problem of GvHD".
However, when clinical trials involving humans begain, it was quick discovered that while GvHD was reduced (not eliminated), there was a huge increase in graft failure (in otherwords, the patients didn't develop an immune system - very bad).
The immune system is a tricky thing. While mice are the experimental model, the experimental results don't always match those from humans. We can do a whole lot of things in vitro to mice cells that we can't even begin to duplicate in human lymphocytes. Additionally, mice and humans don't always share the same functional receptors (mice Ly-108 vs the human KIRs).
I applaud the BBC news report - at least they identified that the study was simply a step, used animals, and didn't cure the mice. The Slashdot summary is simply flat out incorrect.
So this means we can attach a bunch of people to a sick person and redirect all of their immune systems to the sick guy and heal him right?
Although they've more or less gotten pancreas/islet cell transplants working, the major drawback (besides costs and availability of donors) was the fact you were simply trading insulin injections for anti-rejection drugs. The anti-rejection drugs had their own problems, which made this a less than ideal situation. Many people were hoping they'd come up with a way of making "cloned" islet cells from yourself so that your body wouldn't reject them.
Additionally, it's possible they could "fix" a type 1's immune system so it doesn't kill off the islet cells again anyway. And for newly diagnosed type 1's, they could potentially stop it in its tracks, and prevent any further islet cell loss.
...Isotechnika has re-designed our old-standard drugs (Cyclosporin, stuff like that) to be far, far less toxic.
I don't understand it. Sounds good, though!
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Overactive immune systems generally tend to attack healthy tissue (your white blood cells and antibodies NEVER fix damage anyway -- that's not their job).
Let's see you taking over the world with systemic autoimmune disorders.
"Who dares stand against ME! You shall feel the wrath of my lupus, arthritis, blistered skin, depression, blood clots, floater-filled vision, thyroiditis, and myositis!"
Running away, are you?! Come back here, I'll bite your kneecaps off!"
There are only 10 types of people: those who understand decimal, those who don't, and, uh, 8 other types I forget.
When this drug hits the market, and they show commercials with heart transplant recipients dancing in meadows and gathering flowers, the gentle voice doing the voiceover will recite the following disclaimer:
If your immune system is not normal because of advanced HIV disease, make sure your doctor knows this to avoid a potentially serious complication."
Gee, sounds like a good idea!
The whole idea of using stem cell copies to make organs is that they wouldnt be rejected since they have the same make up of your own cells. But with this discovery, we might be able to use animal organs to have unlimited supplies of body parts, perhaps to live forever?
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