AIDS revisited


Given my last missive on the AIDS topic, which I wrote way back in 1992 or so, I thought I'd add the following comments:

For a couple of years we knew that there is far more virus than we originally thought (which was a discrepancy in the HIV-AIDS theory and still hasn't been resolved to my satisfaction). But what's interesting is that mathematicians have teamed up with biologists to understand the dynamics of HIV infection. One of the issues that Duesberg pointed out very quickly was that that when we look at T cells, there is little or no virus present. This was a major paradox. Apparently it has been resolved a couple of weeks ago (Nature 373; January 12, 1995)---the T cells we see in an infected are brand new. Duesberg proponents would argue that he has been right all along (and he has been on the spot picking out the flaws in the old theory) and that perhaps it is his questioning that has stimulated this result.

If this isn't clear, the question (paradox) we're addressing is: why do we see so few virions in an infected person, and how can such a small number account for such a huge CD4 T-cell loss? The virus is no longer credible as the direct killer and I think the new results indicate this fact. Antibodies are indeed coping with the virus (again, prescence of antibodies against the virus are indicative of the fact that the immune system is doing something). The new theory says that infected cells are prevented from producing progeny by HIV-specific cytotoxic T lymphocytes (CTL) or "killer cells". This is the standard way the immune system handles things, but if the virus is resilient, even if it infects only a small number of cells, it will gradually overcome the immune system. This, in one go, explains yet another discrepancy: the latency period going from HIV infection to AIDS. It's a rather elegant theory and whether it is true or not remains to be seen, but it is indeed a much better theory than the earlier one. I heavily recommend checking out the issue of Nature in question if you are at all curious about this.

But do you think it's over? In a recent issue of the New England Journal of Medicine, there is a HIV+ patient who has now lived for 12 years without getting AIDS. His CD4 count is as good as you and I. But the person in question seems to have a HIV with a supposedly pathogenic protein inactivated. So if you look at it cynically, it's one indication that HIV has nothing to do with AIDS. If you look at it optimistically, there might be hope for a live vaccine. Of course, the sample here is very small: one.

The fact is that a lot of bad research has been done on the AIDS front mainly because of political pressure (and this continues to this date, in any area that is a hot topic in medical science because all sorts of people jump the bandwagon). For whatever reasons some good stuff (in the basic science frontier) is being done. Also interesting is that people are returning to the basics and this is the most important thing in my opinion.


Addendum

It is now 1997, and a lot more research has been done that greatly strengthens the link between HIV and AIDS (thanks to some really interesting basic research, which I won't get into here). I want to point out that the questions asked by people like Duesberg were extremely important in prodding the scientific community to provide more rigourous answers. While I don't condone the methods and the way the questions were raised, I think it was important they indeed be raised.


Pseudointellectual ramblings || Ram Samudrala || me@ram.org