Someone please correct me, but I think I read somewhere that the AIDS virus can survive in human blood at room temperature for a few hundred hours. Would it be possible to lower an infected person’s basal body temperature below room temp. to kill the virus? I know I’ve heard the accounts of people being submerged in freezing water being brought back to life, but that’s probably more of an exception than a norm. Or could the person’s blood be “cycled” out of them, and the blood be cooled until the virus is killed, then reheated, and “cycled” back in? Or does the AIDS virus actually get into a person’s bone marrow?
Logically you’d have to say no. The vast majority of blood products are frozen or chilled, and HIV is still one of the major bogies from transfusions, so obviously chilling has little effect on HIV infectiveness. Not really surprising that chilling has little effect, cold rarely kills viruses since they’re not actually ‘alive’ in the normal sense, and have to be destroyed physically to be rendered harmless. If anything, chilling blood would simply decrease the rate of reactions, slow down antibodies and the reactions of macrophages, lymphocytes etc. and increase the chance of the viruses survival.
I don’t know where that ‘survival at room temperature for a few hundred hours’ factoid came from, but I’d WAG that blood products are stored longer than a few days. Unless it’s meant to imply that heating to over 37[sup]o[/sup]C
will destroy HIV. That sounds possible and I’m sure there’s a web site somewhere that could tell you, but I’m too tired and lazy to do a search. Suffice it to say lowering core temperature won’t work.
HIV almost certainly does get into bone marrow, but not specifically. It’s a blood-borne and blood infectious virus, which means it will be found anywhere that has a blood supply. That’s pretty much your entire body excluding the CNS and the testes, so any attempt to cure someone with physical methods like heating/cooling will have to affect the whole body, not just the free circulating blood. Machines for lowering core temperature much as you describe do exist, except the blood isn’t reheated. The devices are designed to lower temperatures for tricky surgery. Pity they wouldn’t work for AIDS treatment though.
There is a controversial treatment, called hyperthermia, that involves cycling a patient’s blood through some sort of heating system to raise the patient’s core temperature. I don’t believe this is permitted in the U.S.
Assuming, hypothetically, that lowering someone’s body temperature far enough (or any other treatment you can think of) would “kill” all the virus particles floating around in their blood, such a treatment wouldn’t be a cure for HIV infection. The reason HIV infection is so hard to cure is that the virus’s genome, which enters a cell in the form of RNA and carries all the information needed to make a new virus, gets copied into DNA and inserted into the middle of a DNA molecule in the nucleus of the cell. Once it’s there the cell can potentially make an indefinite number of new virus particles.
There are a whole lot of cells in different parts of a patient’s body that carry the virus in their DNA, and the only way to really cure the infection would be either to kill every cell that carries it (which might be possible if we could learn how to make the patient’s immune system do it) or to somehow pick out and alter the viral DNA in every one of those cells. This would be difficult since the viral DNA is the same as the cellular DNA except for having a distinctive sequence. It might be possible someday to make a specific change in the DNA of every cell in someone’s body, but it’s a long way off.
I think that in the forseeable future if we don’t learn to prime the immune system to destroy any cell that’s making HIV proteins, the only treatment (other than prevention) will be lifelong drug therapy.