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| Image from Davidson College |
With an
unclear origin, the human immunodeficiency virus (HIV) infection and acquired
immunodeficiency syndrome (AIDS) is a complex mystery that science has been
unable to solve. Of the millions
affected with AIDS in the United States, approximately 1 in 6 is unaware of
their infection and is consequently not seeking any treatment for it. This is particularly relevant because 1 out
of every 4 infections is amongst those ages 13 to 24. Since its discovery in the 1980s, AIDS has
claimed approximately 636,000 lives in the US alone.
A new piece
of the puzzle may have been discovered.
Timothy Ray Brown, otherwise known as the Berlin patient, has rid
himself of the HIV. After living for 11
years on antiretroviral drugs (ARD), Brown was diagnosed with acute myeloid
leukemia. When the chemotherapy did not
work, Brown received a bone marrow transplant.
His immune system was irradiated and his doctor sought out a bone marrow
donor who had a rare mutation that led to a mutated receptor on white blood
cells that would normally lead to infection.
After 7 years, Brown has only trace amounts of viral DNA that is unable
to replicate in its host.
Because of
Brown, three possible factors have emerged in the scientific HIV community that
could lead to a HIV cure. The first is
due to the irradiation of his immune system, the second is the mutated WBC
receptor, and the third is the possibility that Brown’s new immune system
destroyed his original HIV-infected immune system.
A study
conducted by Mavigner et. al, was focused on the bone marrow transplant aspect
of Brown’s cure. This research group
took three rhesus monkeys and extracted stem cells. They then infected the monkeys with
Simian/Human Immunodeficiency Virus (SHIV).
The monkeys were given ARDs for a several weeks. They were then given myeloablative total body
radiation, which reduced their CD4+ helper T-Cells by 94-99%. The monkeys were then given stem cell
engraftment. Unlike Brown, these monkeys
were tested to have rapid rebound of the SHIV.
Although this study was unable to cure the monkeys of SHIV, it does lead
to a new idea about Brown’s cure. That
the role of the graft versus host plays a key role in finding a cure HIV and AIDS.
First of all, this is awesome! Second, I know that after Brown, studies were conducted on rhesus monkeys and from what it sounds, it seems fairly effective! Do you know how long or if it was mentioned whether they would try and replicate this study in humans? Or is that still a no-go?
ReplyDeleteI see that you say they did not find the results that they found in Brown in the monkeys, but you are right that it does take that option off the board. Do you know if they tested the other options on the monkeys at all? Personally, I like the idea of that the radiation caused a mutated WBC receptor. As we know HIV is not detected by our immune system and that is why we can never recover from it. What I wonder is that if that particular mutation allowed Brown's WBC receptor to identify the HIV virus and prevent it from reestablishing in the body. If that is the case, would it be possible to the replicate this mutation in other individuals in order to eradicate the virus from their system? I see that as a viable option if the ethical hurdle can be over come. By that I mean how ethical is it to purposely mutation someones genome? Also could that mutation manifest in other issues that could potential be worse than HIV?
ReplyDeleteAlso even though it probably isn't connected, is it a possibility that the leukemia effected the HIV virus at all? Could it have made it more recognizable to the immune system?