Weill Cornell Medical College scientists say they've determined a protein produced by HIV infected cells prevents immune B cells from producing antibodies.
The finding, say the researchers, could alter the way experts view HIV, helping to explain how the virus evades the immune system during the first days and weeks of infection.
It also helps unravel a paradox in HIV treatment: The fact that patients can have high blood levels of immune T cells and yet still be vulnerable to the virus.
"It's because the virus produces this protein, negative factor (Nef), which enters B cells to prevent antibodies being targeted to HIV," explained lead researcher Dr. Andrea Cerutti, an assistant professor of pathology and laboratory medicine. "This process leaves other, less targeted immune responses intact -- but since they pose little threat to the virus, HIV proliferates."
The findings appear in this month's issue of Nature Immunology.
Copyright 2006 by United Press International
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