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Altered Immune Cells Help Girl Beat Leukemia
An anonymous reader writes "For decades, one of cancer's most powerful weapons has been to corrupt the human immune system. Finally, researchers in Philadelphia have developed a way to turn that weapon against certain cancers, and potentially open the door to a whole new generation of therapies for all manner of cancers. From the article: 'It is hard to believe, but last spring Emma, then 6, was near death from leukemia. She had relapsed twice after chemotherapy, and doctors had run out of options. Desperate to save her, her parents sought an experimental treatment at the Children’s Hospital of Philadelphia, one that had never before been tried in a child, or in anyone with the type of leukemia Emma had. The experiment, in April, used a disabled form of the virus that causes AIDS to reprogram Emma’s immune system genetically to kill cancer cells.'"
http://xkcd.com/938/
A virus is not lethal. It is merely a vehicle, a means of reprogramming cells. Its hardware. The lethality is in the software.
using lethal viruses to help us combat lethal cancers.
Big deal. Lots of things useful things are lethal. Hell, I was injected with a disabled lethal virus a couple weeks ago. Just in time to keep me from being part of this year's flu season. Pretty much every cancer treatment kills things. That's how they work. The goal is to kill the cancer without killing too much of the person with it.
While I understand your concerns, every medical breakthrough has involved risk.
The polio vaccine could have backfired, but it didn't. You and I have grown up without the fear of a disease that plagued every generation up to our parents.
Your link isn't the same research as what the article is talking about though.
The article is about removing a patient's stem cells, using neutered HIV to deliver a payload to them that changes the immune system at a genetic level and then reintroducing the stem cells into the patient. The patient's immune system would then be equipped to kill the cancer. Your link discusses infecting patients with a virus that targets cancer cells preferentially, killing a cancer while at the same time giving the patient only mild symptoms.
On the one had, the article is talking about real, honest to goodness genetic engineering of a living human being which is, quite frankly, science fiction levels of amazing. But it almost universally causes a cytokinetic swarm in the patient as the immune system suddenly knows how to fight massive amounts of what it suddenly sees as infected tissue (actually tumors). The HIV is disabled the same way other viruses are disabled to create vaccines, and even if the patient got HIV somehow that would in fact still be preferable than dying immediately from cancer.
On the other, your article would indicate a cure that would be essentially zero cost to produce. The side affects are minimal but, and this is the proverbial "but" that is probably killing all research on the topic, you also have a virus that is capable of killing the vast majority of one tissue type (tumor) inside the human body. And that is quite frankly terrifying. Until you can quantify how likely or unlikely the virus is to target a different tissue type and how likely is it that the virus is communicable (or could mutate to become so) you won't be trying it out on anyone.
"[using] a disabled form of the virus that causes AIDS"
While true, this is a poor way to describe a lentiviral vector, meant to invoke the idea of using HIV to kill cancer in the minds of readers not familiar with modern molecular biology. HIV is a type of virus called a lentivirus, which itself is a type of retrovirus, which means that it takes the RNA genetic code it has packaged in the virion, chemically transforms it into DNA, and integrates this DNA into the DNA of the infected cell. Lentiviral vectors are designed such that they do this part of the viral life cycle, but are engineered to lack the genes necessary to make more viruses, so the integrated virus is dead on arrival.
In this case, the researchers kept the normal HIV surface receptors so the virus would efficiently target and "infect" T-cells from the patient; normally, lentiviruses are given a generic non-HIV receptor so they can infect any cell type you might be using in your lab experiments. The lentivirus genome contained not the normal viral genes, but a chimeric T-cell receptor designed to stimulate an immune response against CD-19, a surface protein specific to B-cells. Once this chimeric gene is integrated, the T-cells will express it on their cell surface, and stimulate the immune system to target and destroy cells that have CD-19 on them; this kills all the B-cells in the body, both healthy and cancerous. This last point is a problem brought up by TFA, that the patient now essentially has a limited auto-immune disorder as the altered T-cells persist in her body and continue to point them immune system to targeting B-cells, leaving her partially immuno-compromised (which is the funny part about using the "virus that causes AIDS" to do this).
Not just that, but the Virus's physical form is simply a payload mechanism to inject the virus genetic code into healthy cells. The healthy cell that was infected now becomes a virus factory creating tons of new virus cells until it explodes releasing them into your system. There is a very cut and dry hardware to software paradigm here. If we consider that a virus is nothing but a genetic delivery mechanism it instantly becomes the greatest tool humanity has for this type of work. Nothing we can currently create would be even a fraction as effective.
You realize that it costs insurance companies about half a million dollars to treat a cancer patient? And most of that money goes to all kinds of different companies many of them struggling on low margins making an assortment of drugs, medical services, and other stuff. Now let's say a company comes out with a cure for cancer .. They can charge $100,000 for it as pure profit .. Insurance companies would gladly pay. 10 million people a year get cancer .. That means the profit will be an absolutely insane $1 trillion dollars a year.
Or forget that .. Steve jobs had cancer and died of it .. All a company that had the cure had to do was call him up and charge him $5 billion cash plus 50% ownership of Apple for the cure.
Holy crap. Imagine if they could make sexually-transmitted cancer cures?
Unfortunately, the population of slashdot will STILL be decimated by cancer. But the rest of the world would have a field day!!
That's more than a little misleading. The drugs used in chemotherapy are chosen because they preferentially kill fast-growing tissue first, such as hair, the intestinal endothelium (lining), and tumour cells. It's not as simple as taking some arbitrary, nondescript "poison" under the assumption that the cancerous tissue is poorly equipped to handle all toxins; specific mechanisms are chosen to limit the impact that the drugs have on the rest of the body.
The GP also made a bad comparison since, as the AC also said, inactivated viruses in this form have no replicative ability whatsoever. They're just gene syringes. These same misconceptions arose the last time we discussed retroviral leukaemia treatments.
Bio questions? Ask me to start a Q&A journal. Computer analogies available for most topics!