A study comparing the effects of immunodeficiency virus in humans to its effects in sooty mangabey monkeys, which do not become ill when infected, revealed two major differences in the monkeys' responses to the infection. The findings could open the door to groundbreaking approaches to AIDS treatments, said Dr. Donald Sodora, an assistant professor of internal medicine at UT Southwestern who contributed to the study.

The findings are being published online today at www.immunity.com and will appear in a future edition of Immunity.

"The mangabeys have just as much virus in their system as during pathogenic HIV infection of humans. The riddle is, they don't get sick," Sodora said. "The idea is, you look at the monkeys and you try to unravel that riddle. And as you unravel it, you can begin to develop new and innovative ideas that have not been explored by others for preventing the progression of AIDS in HIV-infected patients."

Mangabeys exposed to long-term, high-levels of SIV the version of immunodeficiency virus found in primates remain healthy and free of any sign of immune deficiency. Researchers found that this lack of symptoms occurred because, unlike humans, these primates have only low-level immune system responses when infected with SIV and do not lose their ability to make new T cells.

T cells, a cornerstone of the immune system, assist other immune cells in eliminating infection. SIV infection in primates and HIV infection in humans both cause a depletion of these cells.

In contrast to the mangabeys, humans infected with HIV respond with an aberrant activation of the immune system that leads to further de
'"/>

Contact: Rachel Horton
rachel.horton@utsouthwestern.edu
214-648-3404
UT Southwestern Medical Center
17-Mar-2003