John Hopkins scientists have altered HIV virus in such a way that it loses its ability to suppress the immune system.
Their work could remove a major hurdle in HIV vaccine development and lead to new treatments, said the scientists.
Typically, when the body's immune system cells encounter a virus, they send out an alarm by releasing chemicals called interferons to alert the rest of the body to the presence of a viral infection.
When the immune cells encounter HIV, however, they release too many interferons, become overwhelmed and shut down the subsequent virus-fighting response.
The researchers treated HIV with a chemical to remove cholesterol from the viral coat. Then they introduced either the cholesterol-diminished or normal HIV to human immune cells growing in culture dishes, and measured how the cells responded.
The cells exposed to cholesterol-diminished HIV didn't release any initial-response interferons, whereas the cells exposed to normal HIV did.
"The altered HIV doesn't overwhelm the system and instead triggers the innate immune response to kick in, like it does with any first virus encounter," said David Graham, Ph.D., assistant professor of molecular and comparative pathobiology and medicine. By altering the virus, explained Graham, the researchers were able to reawaken the immune system's response against HIV and negate HIV's immunosuppressive properties.
The study has been published online September 19 in the journal Blood.