Chronic Infection Now Clearly Tied To Immune-system Protein

[J220]

http://www.sciencedaily.com/releases/2009/05/090514153036.htm

Chronic Infection Now Clearly Tied To Immune-system Protein


ScienceDaily (May 16, 2009) — The reason deadly infections like human immunodeficiency virus (HIV) and hepatitis C never go away is because these viruses disarm the body's defense system. Researchers at the University of Alabama at Birmingham (UAB) have discovered that a key immunity protein must be present for this defense system to have a chance against chronic infection.

Research up to now has tried but failed to decipher the cross-talk between 'killer T-cells' and 'helper T-cells' in the fight against viruses. The new UAB study finds this cross-talk can only happen in the presence of interleukin-21, a powerful immune system protein. If interleukin-21 is missing for whatever reason, then the immune system's anti-viral efforts fail, said Allan Zajac, Ph.D., an associate professor in UAB's Department of Microbiology and lead author on the study.

The findings are published in the journal Science.

"Adding interleukin-21 back in stimulates the immune response and controls the infection," Zajac said. "We demonstrate that the loss of this protein prevents the control of the infection and diminishes the function of the killer T-cells, specifically CD8 T-cells."

The study mice were treated for lymphocytic choriomeningitis, a viral infection of the membranes surrounding the brain and spinal cord. Measurements were taken for two types of T-cells, CD4 and CD8 T-cells, before and after the mice were treated with interleukin-21.

"Interleukin-21 served as the key messenger between the T-cells, whereas before we didn't know exactly how the two types of cells communicated with each other," Zajac said. The CD4 T-cells help the immune system do its job by boosting CD8 T-cells' ability to fight and kill viruses.

Co-authors on the study include John Yi and Ming Du, Ph.D., both of UAB's Department of Microbiology. Research funds came from the National Institutes of Health.

[freewillie99]

Is this big?

[J220]

In one way yes, because the reasearch has shown that the absence of interleukin-21 directly resulted in failure to control infection, and when they reintroduced it infection was controlled. Now, I don't know exactly what they mean by "controls" (in bold in the original article). Clearing vs. just keeping it in check (which to be honest, if this can be done without medication, like with LTNP then that in itself would be huge.

The open questions of course are whether this will translate into humans (they used mice, but I am not clear if they used the new generation of mice that have been genetically modified to be a copy of the human immune system) , and whether reintroduction of interleukin-21 will be sufficient to overcome whatever method the virus uses to interefere with the interleukin-21 in the first place.

But one thing is for sure, every time a new piece of the puzzle is discovered, it takes us that closer to our dream of defeating hiv.

From a personal subjective perspective, I think this is very important, because if lack of communication betweet CD4 and 8 is pinpointed to be the reason hiv infection persists, and we can reestablish communication there is a possibility that the body can clear the virus o its own once and for all. Cheers.

[Inchlingblue]

But one thing is for sure, every time a new piece of the puzzle is discovered, it takes us that closer to our dream of defeating hiv.

I agree. Knowledge is power. Even when the results of research seem on the face of it to be "bad" news, such as the recent finding that the shape of antibodies renders them unable to bind to the surface of HIV, it's still important to know since it does represent another piece of the puzzle. This finding re: interleukin-21 sounds pretty important to my layman's ears.

I guess my only concern is that with ever-increasing pieces of this puzzle coming to the fore, I wonder who if anyone is keeping track of it all so that the puzzle can be put together and solved. I wouldn't be surprised if the answer to the HIV problem is already under our noses.

[veritas]

I guess my only concern is that with ever-increasing pieces of this puzzle coming to the fore, I wonder who if anyone is keeping track of it all so that the puzzle can be put together and solved. I wouldn't be surprised if the answer to the HIV problem is already under our noses.

Inch,

The groups that should be responsible for putting all the info together are: IAVI,CHAVI,NIAD etc.
But it will take time to incorporate all these finds.


v

[Inchlingblue]

There was a recent thread about this that identified the research as coming from UCLA......hmmmm.

"Scientists Identify How Key Protein Keeps Chronic Infection In Check" is the name of the other thread

LINK:

http://forums.poz.com/index.php?topic=27079.0


Does this mean that two different researchers "discovered" this at about the same time? There's something not adding up here, unless I'm missing something.

[J220]

It's likely they worked separately on the same principle and reached the same conclusion. This has happened before, there was some discovery made a year or two ago (can't remember exactly what it was) that was announced almost simultaneously by different researchers.

In any case I think it bodes well for this that two different teams confirmed each other's findings. And remember there is no "intellectual property" when it comes to areas of ressearch, only to substances and very specific methodologies for achieving biochemical goals. So you can have a half dozen teams working on the same thing. Let's hope this leads somewhere.