FRIDAY, Sept. 23, 2005 (HealthDay News) -- Macrophages, immune system cells that fight infection, may help cause the dementia seen in some patients with HIV, according to a new study.
Researchers at the University of Florida and the University of California, San Francisco, found that macrophages, in their attempts to attack HIV, may damage the brain's temporal lobe, where many memories are stored.
Because HIV mutates almost 100 times faster in the temporal lobe than in other parts of the brain, large numbers of macrophages migrate to this area to attack the virus, resulting in a potentially damaging inflammation.
"In a way, it's not the virus that causes the dementia," researcher Marco Salemi, a UF assistant professor of pathology and immunology, explained in a prepared statement. "It's the fact that there is this continuous migration of infected macrophages to the temporal lobe. The virus mutates much faster there, [so] the macrophages keep accumulating and keep creating this inflammation that leads to dementia."
About 15 percent of people with HIV will develop dementia as their disease progresses. This research may help scientists find ways to block the migration of macrophages to the brain and prevent HIV-associated dementia, Salemi said.
The study was published in the Journal of Virology.
Project Inform has more about HIV/AIDS and dementia.