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Doctors Will Test Gene Editing On HIV Patients
Soychemist writes "Some people have a mutation that makes them highly resistant to HIV, and scientists think that they can give that immunity to anyone with a new type of gene therapy. The first human trials will start at the University of Pennsylvania this week. Researchers will draw blood from people with drug-resistant HIV, clip the CCR5 gene out of their T-cells with a nuclease enzyme, grow the modified cells in a dish, and then return 10 billion of them to the patient's bloodstream. Those cells will be immune to the virus, and they will keep the patient's T-cell count up even if the rest are destroyed. 'We will see if it is safe and if those cells inhibit HIV replication in vivo,' said the lead researcher. 'We know they do in the test tube.'"
Every time someone posts about HIV we get a jackass like you. There are people who have HIV and didnt contract it through sex or drugs.
There are people who were born HIV+ because their mother was a carrier, there are people who have been raped and now carry the virus, there are people in the medical field that contract it because some drug addict freaks out while they tend to them. Hell, even though we test blood now many people contracted it through blood transfusions before they tested it.
Oh and by the way. Condoms don't give 100% protection against HIV its about 80-85%.
HIV is a bastard of a virus. Our immune systems can usually handle most viruses without intervention. You cant win on your own against HIV. It will destroy the immune system eventually.
If this treatment is successful at this level. At least we can give life to those who didn't have the choice.
If you RTFA, its people who have drug-resistant HIV who are being experimented on.
The test subjects have drug resistant HIV.
There are 3 big risks / problems I see with this approach:
#1: The modified T-Cells attack the host after they are reintroduced. Think of it like auto-immune disease or transplanted-organ rejection. This could cause effects ranging from a mild food allergy to death. Anyone know how much damage 10 billion rogue T-cells could do? I sure don't; however, I do know that they aren't a straight 1 T-Cell used up for each 1 antigen.
#2: Unmodified T-cells attack the modified T-Cells because the surface of the modified T-Cells (i.e. the CCR5 protein) could possibly trigger an immune response. This would render the modified T-Cells kind of pointless. Seems like this would have better chance of working on patients with full blown AIDS rather than merely HIV+.
3: Modified T-Cells survive and are unaffected by HIV; however, these surviving modified T-Cells are just clones of the one original T-Cell that the lab modified. So in essence, you have injected the test subject with 10 billion of the same T-Cell. Unless the doctors have a way of massaging the genes on a representative sample of T-Cells, then this is kind of useless to the patient. What good are 10 billion T-Cells if they are each only good for tagging one antigen? Meaning, that the 10 billion T cells could only respond to a single stimulus, i.e. they could all only fight one strain of the common cold, but not anything else.
Disclaimer: I have a BA in bio from a public ivy; however, my GPA wasn't that great, and I didn't pursue a career in the field. I very well could be overlooking something substantial in immunology etc.
Actually, this is far from the truth. I am an HIV-positive individual and based on the fact that my HIV was detected early and also that I started on HIV medications within the first year of contracting it my lifespan has been extended to the point where I will most likely live a full life. Before contracting HIV I thought it was a terrible thing to have and that I would kill myself if I ever got it. I have news for you: it is a terrible thing, but just like everything else in the world you get over it and with HIV medications having nearly NO side effects and once-to-twice daily dosing it makes life worth living.
While some may speculate on whether or not I really know what I'm talking about, I do. I am a healthcare professional. For those of you who are wondering why I didn't post this under my account, I would rather not taint Google's results with gossip for my next employer. :)
T cells are produced by the bone marrow. They don't reproduce on their own.
The lifespan of an average T cell is on the order of 10-20 weeks. I believe. Shorter in HIV patients.
Who knows? But not necessarily. After all, you get plenty of foreign T-cells with a blood transfusion. But I don't think anyone is necessarily viewing this treatment as a 'cure' in itself.
That's not known. But they've done it, with positive effects. Note how 'cure' is put in quotes, as it should be.
That is ridiculous. It's neither.
For the most part, T-cells die off naturally.
People infected with HIV do not have to deal with a problem of too many t-cells, so in this case it's not much of a concern.
Most importantly though, T-cells do not replicate to create more T-cells. They come from a type of lymphocyte starter cell (a stem cell essentially), which reproduces in the bone marrow.
Taking t-cells from your body, and then reintroducing them to your body will not give you leukemia (literally meaning "White Blood", refers to various cancers of white blood cells).
More than likely this is just a test, not *the cure*. The point being to see if the modified t-cells survive long enough to keep the count from dropping (as it would via a normal HIV infection). If it does work, then we can start developing methods to modify bone-marrow in order to make the new t-cells your body creates have the altered gene.
Of course, I'm not an expert, and the article is unfortunately slim on details, so this is basic speculation.
Not to be a wet blanket for your argument, but this is being tried on drug-resistant HIV patients.
There are lots of engineers involved. My father ran a small medical startup some years ago and they made a very high tech (for the time) artificial ventilator that used rapid pulses of air rather than the typical high pressure slow pulses. They did lots of experiments on animals and had to jump through all kinds of hoops with the FDA just to be allowed to put the ventilator on a human subject. Essentially the only way, after the animal trials, to get the ventilator on a human patient was for the patient to be unresponsive to conventional treatment, at significant risk of death without intervention, and received signed autorization from the patient or guardian. (get those living wills drawn up and signed if you haven't already!)
It took years, huge personal and venture capital investment, and eventually the company was bought out and I think the techology disappeared or otherwise got incorporated into standard ventilators. I posted this to illustrate all the work that needs to go into a medical device before it is allowed to be tried on humans... and even then, promising, even successful technology does not always make it in the marketplace. Believe it or not, Doctors are some of the *worst* luddites around and it is incredibly difficult to get enough momentum for a new technology to take hold.
This post brought to you by your friendly neighborhood MBA.
You could be worse off, as the study may require that you go off the regular HIV cocktail you are taking to suppress it.
They would find it hard if not impossible to get ethical approval for that kind of study. If an effective treatment exists, controlled trials are controlled against that, and not against a placebo.