Design of HIV Vaccines May Have Been Faulty
Immune systems attacked antibodies, study claims
THURSDAY, April 28, 2005 (HealthDay News) -- New information about how HIV evades the body's immune system may lead to more effective approaches to creating a vaccine, says a Duke University Medical Center study.
The study results suggest that HIV vaccines may have been ineffective in the past because they induced production of antibodies that are attacked by the recipient's immune system.
The Duke researchers found that certain antibodies that recognize and attach to the HIV protein gp41 resemble antibodies made in autoimmune diseases. In most people, the immune system attacks and destroys these kinds of antibodies.
Attempts to create HIV vaccines may have failed, in part, because specific proteins on the protective outer layer of HIV trigger only short-lasting, self-reactive antibodies rather than long-term, HIV-specific antibodies, the study said.
The findings also suggest that, during the initial infection stage, HIV may avoid destruction by the body's immune system because these outer-coat proteins on HIV activate self-reactive antibodies.
"The fundamental problem in all of HIV vaccine research has been that when you inject the envelope of HIV virus into people or animals, no broadly neutralizing antibodies -- those antibodies that kill most HIV strains -- are made," study lead author Dr. Barton Haynes, director of the Human Vaccine Institute at Duke, said in a prepared statement.
"This provides a plausible explanation for why broadly protective antibodies have not been made in response to currently tested HIV vaccines," Haynes said.
The study appears online April 28 in Science Express.
The American Academy of Family Physicians has advice on how to reduce the risk of HIV/AIDS.