‘Controllers’ provide clue to AIDS infection
David Haas, M.D.
The finding, published in this week’s Science magazine, could speed development of a vaccine against the human immunodeficiency virus (HIV), said David Haas, M.D., who led the Vanderbilt part of the study.
About one in every 300 infected people is an HIV “controller,” someone who is able to keep the virus from replicating and causing illness without the aid of anti-retroviral therapy (ART). In 2006, an international effort was launched to find out why.
The International HIV Controllers Study (www.hivcontrollers.org) compared the genetic material collected from nearly 1,000 “controllers” all over the world to more than 2,600 others with progressive HIV infection.
The technique, called a genome wide association study, found that several specific amino acid variations involving genes that encode for the HLA-B protein were associated with whether individuals could control HIV with their immune system only.
HLA-B is part of the human leukocyte antigen (HLA) system that helps the immune system identify and attack proteins made by foreign invaders such as viruses. Normally the HLA-B protein latches on viral protein segments made in cells that have been infected, marking the cell for destruction by the immune system.
It may be that some people have more effective “marking” systems.
More than 300 researchers from around the world contributed to the study, which was led by investigators from the Ragon Institute of Massachusetts General Hospital, MIT and Harvard, and from the Broad Institute of MIT and Harvard.
Haas coordinated the study’s access to the Human DNA Repository, part of the federally funded AIDS Clinical Trial Group, which is housed in the Vanderbilt Center for Human Genetics Research. The repository comprises extracted DNA samples from more than 13,000 participants in HIV clinical trials in the United States and is being expanded internationally.
“This highlights the critical importance of DNA repositories,” said Haas, who directs the Vanderbilt Therapeutic AIDS Clinical Trials Program.