Posted on 03/27/2005 8:21:47 PM PST by Flavius
WITHIN days of infection, the AIDS virus destroys more than half of the immune cells that might recognise and help fight it, US researchers have found.
The discovery might force a re-evaluation of how to tackle the deadly infection.
Two separate studies in monkeys showed that SIV, the monkey version of the human immunodeficiency virus or HIV, attacked CD4 memory T-cells right away and wiped out more than half of them.
"The findings may require a rethink of strategies to design HIV drugs and vaccines," said Dr Mario Roederer, of the National Institute of Allergy and Infectious Diseases.
The findings will be difficult to replicate in people, because most people do not know the moment they are infected with the AIDS virus, which gradually destroys the immune system, leaving patients vulnerable to numerous infections.
But SIV is a good model and works in a similar way.
Both teams, whose findings were reported in the journal Nature, worked with monkeys that they infected with SIV.
They then watched what happened to their immune cells.
Right away the virus attacked the CD4 T-cells that had the correct configuration for the virus. Normally during an infection such cells would recognise and latch onto an invader, helping other components of the immune system destroy it.
But HIV is different because it targets the immune system, and the two studies have revealed how quickly it makes it impossible for its victims to launch a defence.
Dr Roederer's team used new, sensitive tests to show just how the virus moved so quickly.
"Specifically, 30 per cent to 60 per cent of CD4 memory T-cells throughout the body are infected by SIV at the peak of infection, and most of these infected cells disappear within four days," the researchers reported.
"Furthermore, our data demonstrate that the depletion of memory CD4 T-cells occurs to a similar extent in all tissues. As a consequence, over one-half of all memory CD4 T-cells in SIV-infected macaques are destroyed directly by viral infection during the acute phase - an insult that certainly heralds subsequent immunodeficiency."
Any attempt to vaccinate against HIV or to provide efficient treatment must stop this process right away.
Dr Ashley Haase and colleagues at the University of Minnesota Medical School made similar findings. Not only did the virus directly kill the CD4 cells, they found, but it also causesd them to them to commit cell suicide.
There is no cure for HIV infection, which killed more than 3 million people globally last year.
Drug cocktails can control the infection, but it comes back quickly if they are stopped. More than two dozen vaccines are being tested, but experts do not expect any of them to prevent HIV infection in substantial numbers of people.
His morality does not negate the fact that his statement, however, crude is truth.
The Super HIV bug is now upon us and has been conclusively linked to another patient zero.
This mutated not from mosquitos or blood transfusions but from careless and casual unprotected sex by already HIV+ homosexuals.
You're making me sick. (not you, what you posted.)
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