Scientists at Boston's Massachusetts General Hospital say they have discovered why the immune system cannot fight the HIV virus.
Bruce Walker, head of the Boston team, said the body's virus-attacking T-cells are turned off by certain diseases including human immunodeficiency virus, which causes AIDS, CBS News reported Tuesday.
"One hypothesis has been that they become inactivated. One hypothesis is that that they became destroyed," Walker said. "What this study shows us is actually that those cells are there, that they fully function; it's just that they have been turned off."
He said HIV activates a molecular switch in the cells that turns them off, but he and his team were able to reactive the cells in a laboratory setting. He said the process might someday help fight HIV, cancer and Hepatitis C.
"We really don't know what happens when we try this with humans," Walker says. "But it opens a new pathway for us to pursue. But we really need to proceed with caution."
Copyright 2006 by United Press International
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