Some good news in the fight against HIV. The first patient has been declared 100% cured of HIV.

[Statistical]

His therapy is nothing short of drastic but hopefully this will open doors to new treatments and eventually a widespread cure and/or vaccine.

Some background:
A small % of the population is immune to HIV infection, the exact % of humans affected vary significantly by race and geography so estimates range from <1% to almost 10% in localized studies. A sucessful HIV infection requires the presence of CD4 and CCR5 receptors. Humans with this mutation lack the CCR5 receptors making HIV infection impossible. One thing to consider is that evolution and natural selection in the absence of HIV treatment over the course of thousands of years would gain dominance (as vulnerable humans die off and "immune" humans flourish). Science has simply provided a mechanism to transplant this mutation.

The therapy:
His doctors used chemo and full body therapy to completely kill his own immune system. They then did a full stem cell bone marrow replacement from a donor with the required mutation (lacking CCR5 allele). Due to no immune system his body accepted the foreign stem cells as his own and they rapidly took over his bone marrow killing off his existing bone marrow in the processes. When he recovered his body didn't reject the transplanted marrow and HIV lacking a suitable host died off. He has been on absolutely no anti-virals since the treatment and doctors are no confident enough to declare him HIV free.

The simple-simple version:
They killed his immune system and transplanted an immune system that is resistant to HIV to allow his body to "naturally" fight off HIV.

Article for the masses:
http://gizmodo.com/5713498/man-officially-cured-of-hiv

The source in New England Journal for those medically inclined:
http://www.nejm.org/doi/full/10.1056/NEJMoa0802905

The followup article showing no presence of HIV and claim of "cured" (4 years after therapy):
http://bloodjournal.hematologylibrary.org/cgi/content/abstract/blood-2010-09-309591v1

[thereismore]

1. Immune is the right word. HIV needs to bind to a T cell to infect it, and the donor

is lacking the protein that HIV binds to, so HIV never enters the donor T cells and is gradually lost from the body.

[Statistical]

2. Thanks for clarification I updated the post.

[xchrom]

3. It's too expensive. Period. Nt

[Statistical]

4. It also has a 2/3 death rate. Nobody says it is a routine treatment.

Most HIV patients would be better off simply taking anti-virals than taking the risk of this treatment. However prior to this there was no evidence that AIDS even could be cured. Prior to first open heart surgery many heart aliments were simply considered fatal. Medical science has to start somewhere and now for the first time in history of the HIV virus a cure is possible.

It is possible simpler, less invasive methods to alter the host DNA to include the mutation via gene therapy may be possible someday.

[xchrom]

5. No d'uh. Nt

[Lord Magus]

8. The fact that this guy is now immune to HIV could be the key to a vaccine, though.

[The Backlash Cometh]

6. How do you make an immune system that is resistant to HIV?

[Statistical]

7. You can't.... however HIV can't infect T-cells which lack CCR5 receptor

Most humans T-cells have CCR5 receptor and thus are vulnerable to HIV virus attack on T-cells. If your T-cells have CCR5 receptor then you are vulnerable to HIV infection.
Some humans (1%-10%) have a mutation which causes the T-cells to lack the receptor to not exist. No CCR5 receptor = no mechanism for HIV to infect T-cells.

To date there is no know way to alter one DNA to gain the mutation (remove CCR5 receptor) even 20 years ago nobody knew this mutation existed. However in this therapy they killed off the patient immune system and transplanted bone marrow stem cells which contained the CCR5 mutation (and thus natural immunity to HIV). Those cells took over his body bone marrow production. The T-cells (which are produced in bone marrow) lacked the CCR5 receptor and thus were immune to infection by HIV. Eventually HIV in his body lacking suitable T-cells to infect died off.

Essentially the therapy works because HIV infects T-cells and to do so need T-cell with the CCR5 receptor present. After the treatment HIV couldn't infect the T-cells in his body and died off due to lack of viable host.

In short they didn't modify his immune system they transfered an immune system which is naturally resistant to HIV into his body. Before now that hadn't been done.

[The Backlash Cometh]

9. That's a Wowzy!

Thanks for the great explanation.

I suppose that donors (or their survivors?) that have the mutation should be compensated?

[slipslidingaway]

10. Interesting and thanks, I see the person underwent two allo transplants after AML ...

was diagnosed.

From you link

February 12, 2009

http://www.nejm.org/doi/full/10.1056/NEJMoa0802905#t=article

"...Case Report

A 40-year-old white man with newly diagnosed acute myeloid leukemia (FAB M4 subtype, with normal cytogenetic features) presented to our hospital. HIV-1 infection had been diagnosed more than 10 years earlier, and the patient had been treated with HAART (600 mg of efavirenz, 200 mg of emtricitabine, and 300 mg of tenofovir per day) for the previous 4 years, during which no illnesses associated with the acquired immunodeficiency syndrome (AIDS) were observed. At the time that acute myeloid leukemia was diagnosed, the patient's CD4 T-cell count was 415 per cubic millimeter, and HIV-1 RNA was not detectable (stage A2 according to classification by the Centers for Disease Control and Prevention). Initial treatment of the acute myeloid leukemia consisted of two courses of induction chemotherapy and one course of consolidation chemotherapy. During the first induction course, severe hepatic toxic effects developed and renal failure occurred. Consequently, HAART was discontinued, leading to a viral rebound (6.9×106 copies of HIV-1 RNA per milliliter). The therapy was resumed immediately, before a viral steady state was reached, and 3 months later, HIV-1 RNA was undetectable.

Seven months after presentation, acute myeloid leukemia relapsed, and the patient underwent allogeneic stem-cell transplantation with CD34+ peripheral-blood stem cells from an HLA-identical donor who had been screened for homozygosity for the CCR5 delta32 allele...

...Except for the presence of grade I graft-versus-host disease of the skin, which was treated by adjusting the dosage of cyclosporine, there were no serious infections or toxic effects other than grade I during the first year of follow-up. Acute myeloid leukemia relapsed 332 days after transplantation, and chimerism transiently decreased to 15%. The patient underwent reinduction therapy with cytarabine and gemtuzumab and on day 391 received a second transplant, consisting of 2.1×106 CD34+ cells per kilogram, from the same donor, after treatment with a single dose of whole-body irradiation (200 cGy). The second procedure led to a complete remission of the acute myeloid leukemia, which was still in remission at month 20 of follow-up..."

[Statistical]

11. Shameless bump for morning crowd. n/t