Researchers Crack Major HIV Mystery 84
mrspoonsi sends this news from Scientific American:
"The difference between HIV infection and full-blown AIDS is, in large part, the massive die-off of the immune system's CD4 T-cells. But researchers have only observed the virus killing a small portion of those cells, leading to a longstanding question: What makes the other cells disappear? New research shows that the body is killing its own cells in a little-known process. What's more, an existing, safe drug could interrupt that self-destruction, thereby offering a way to treat AIDS. The destructive process has caught scientists by surprise. 'We thought HIV infects a cell, sets up a virus production factory and then the cell dies as a consequence of being overwhelmed by virus. But there are not enough factories to explain the massive losses,' says Warner Greene, director of virology and immunology at the Gladstone Institutes, whose team published two papers today in Science and Nature describing the work. Greene estimates 95 percent of the cells that die in HIV infections are killed through pyroptosis, so the findings raise hope for a new type of treatment that could prevent HIV from progressing into AIDS. 'Inhibiting activation of the immune system is not a new concept, but this gives us a new pathway to target,' says Robert Gallo. And in fact, a drug already exists that can block pyroptosis."
Re:Both Science and Nature? (Score:5, Interesting)
If you don't publish papers, you don't get funding. Sucks, but that's what we get for budget cut after budget cut, tax cut, after tax cut.
The big question appears to be if the latent infected cells can clear or deactivate HIV, or if they'll happily activate, travel to the site of an infection of some other kind, then start spewing HIV everywhere.
This process is basically cells realizing they are being infected (virus) or eaten (bacteria) by a foreign organism, and responding by killing themselves and spewing massive amounts of chemicals that alert the immune system to the problem. Normally, this recruits other immune cells to the site and is probably the right strategy 99% of the time. The problem is when the infected cells are immune cells themselves, their death just recruits more immune cells to an area with a higher chance of picking up HIV. What they found was that the body's stockpile of immune cells in the spleen, etc (normally dormant, awaiting an infection) get infected by HIV, but don't replicate the virus due to being inactive, however they are active enough to sense the virus in their DNA and kill themselves before repair mechanisms can remove or deactivate the virus genes.
The drug mentioned apparently shuts down or reduces this pathway, opening you up to a higher risk of bacterial infection but slowing or stopping the massive die-off of immune cells (assuming they are able to clean themselves up).
So, is HIV still the cause?? (Score:5, Interesting)
HIV only kills ~5% of the T-cells.
Newly discovered pyroptosis pathway kills the other 95%
This is a radical departure from the accepted mechanisms of how HIV works. Pyroptosis can be triggered by a boatload of different inflammatory processes, I'll be looking forward to their smoking gun that HIV is the cause.
With all the research money poured into HIV research, it's taken them 20 years to notice this?
Re:So, is HIV still the cause?? (Score:4, Interesting)
HIV only kills ~5% of the T-cells.
Newly discovered pyroptosis pathway kills the other 95%
This is a radical departure from the accepted mechanisms of how HIV works. Pyroptosis can be triggered by a boatload of different inflammatory processes, I'll be looking forward to their smoking gun that HIV is the cause.
With all the research money poured into HIV research, it's taken them 20 years to notice this?
Hi! Your comments are a sterling example of the dangers that having just a little knowledge in a certain field poses. As a doctor who has worked in an HIV clinic, let me give you the best practical proof for your reinventing of the wheel. Take an AIDS patient who is sick with an opportunistic infection. Cure the infection, and start the patient on a good regimen of anti-HIV medications. In most patients who aren't too far gone, their immune systems will rebound, and as long as they're compliant with taking their meds, the odds are they will never reexperience the practical consequences of an AIDS diagnosis.
Testing positive for HIV used to be a death sentence. Now with current anti-HIV meds, HIV can be relegated to a chronic illness less burdensome, and less deadly, than type 2 diabetes mellitus. Do you understand that? Treatment of an HIV infection can prevent the onset of AIDS, a clinical syndrome.
If you want a better proof, have a scientist inject you with HIV virus. Make a journal, and see what happens in 5 years.
Re:So, is HIV still the cause?? (Score:5, Interesting)
Or is it just a weak virus that cannot survive inside an uncompromised immune system and thus serves as a great diagnostic for immune problems that it does not actually cause?
You are confusing legitimate high quality research with HIV denialist fiction. This work describes a new and potentially very important mechanism by which HIV infection and partial replication lead directly to cell death. Uninfected cells are not dying. Uninfected patients are not developing AIDS. Unfortunately, HIV denial is one of the more harmful conspiracy theories, leading to (e.g.) hundreds of thousands of avoidable AIDS deaths in South Africa when scientifically uninformed officials were in charge of health policy.