May 28, 2008

Scientists Break Into HIV 'Hideout'

WEDNESDAY, May 28 (HealthDay News) -- Researchers have confirmed that a certain type of cell provides a "hideout" for HIV during drug treatment and is a reservoir of HIV in humans.

These follicular dendritic cells (FDCs) are located throughout the body in specialized sites known as lymphoid tissues, said researchers at Brigham Young University and Johns Hopkins School of Medicine.

FDCs act as "vaults" to store material needed to maintain the immune system's legions of antibodies. When there's a drop in a particular kind of antibody, FDCs release proteins that trigger an immune response to increase levels of those antibodies.

The researchers discovered that FDCs have such an effective vault mechanism that HIV can remain out of reach of drugs flowing through the blood stream. This finding that FDCs harbor HIV may help scientists find ways to attack HIV taking shelter in these reservoir cells.

The study was expected to be published in the June issue of the Journal of Virology.

"One of the biggest obstacles in treating patients with HIV is the establishment of these reservoirs that resist treatment," principal investigator Greg Burton, a BYU biochemistry professor, said in a prepared statement. "The ability to understand the virus in these reservoirs, and to characterize the reservoir itself, provides information with which we can begin to try to devise strategies that target the virus in these reservoirs."

Previous research has shown that two other types of cells -- macrophages and latently infected CD4+ T-cells -- are reservoirs of HIV. It was suspected that FDCs also acted as HIV reservoirs, and this new study confirmed that suspicion.

More information

The National Institute of Allergy and Infectious Diseases has more about HIV/AIDS.

-- Robert Preidt
SOURCE: Brigham Young University, news release, May 2008
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