Researchers
examine HIV “controllers”

AIDS researchers are looking closely at "elite controllers" and "viremic controllers," HIV-positive people whose immune systems are able to naturally suppress HIV viral loads to undetectable or to very low levels, respectively, the Los Angeles Times reports. The scientists aim to better understand how these HIVers are able to control the virus without the use of antiretroviral drugs in the hopes of developing new treatment approaches based on their findings.

"I would say we still don't have the faintest idea why these people are doing as well as they are," Bruce Walker, director of Partners AIDS Research Center at Massachusetts General Hospital, told the Times. "Achieving the state that these guys have reached in their bodies--if we could do that through some intervention, we would solve the AIDS epidemic."

But the research is complicated, and results so far have been confusing. For example, researchers in San Francisco who studied 50 elite controllers found that half had powerful CD4-cell responses to HIV that kept the virus in check, but the other 25 subjects did not have the same immune response. A study in San Francisco suggested that the immune systems of elite and viremic controllers are better able to identify and coordinate attacks against key HIV proteins than the immune systems of those who experience average HIV disease progression. Other researchers suggest that controllers may be infected with defective forms of HIV that are incapable of routine replication and that these defective viruses could hold the key to HIV vaccine development.

The very low number of elite and viremic controllers also hampers the research. These HIVers are very rare--only about 2,000 have been identified in the United States, accounting for only 0.33% of all U.S. HIV patients--and they're spread out all over the country. Because of this, most studies of HIV controllers to date have been small.

But Walk and other researchers at Massachusetts General Hospital are forming a large nationwide study they hope will provide statistically significant results. They've currently enrolled 76 elite controllers and 100 viremic controllers from across the country and hope to include as many other similar HIVers as possible. "Basically, we want to recruit every single one of these people," Walker told the Times. "We have to have a large enough sample to begin to see patterns in this population." (The Advocate)