VA Northern California Health Care System
MARTINEZ, Calif. – A study of HIV conducted by researchers at VA Northern California Health Care System in Martinez, California showed that greater than 86 percent of uninfected adults have antibodies with characteristics potentially capable of protecting them against HIV infection.
The results of the study appeared in the Scientific Reports on Nov. 24, 2016. The report describes the unexpected finding that a majority of adults without HIV infection have antibodies that improves interferon production. The antibody identified by Tom Lum and Dr. Jon Green has the potential to act like a “natural” vaccine and prevent people from becoming infected with HIV, say the researchers.
How do the naturally produced antibodies work?
The researchers were interested in understanding how large numbers of people can be exposed to HIV, but only a few contract the virus. This led to the discovery of a natural antibody that enhances the production of large amounts of a virus-fighting protein called interferon. Interferon is a powerful component that protects against most viruses. The study results suggest that people with the natural ‘anti-HIV’ antibodies will produce high amounts of interferon within 24 hours or less of exposure to the virus; whereas, those who lack the natural antibodies will produce only small amounts later in the infection process. Science has shown that the first 24 hours are critical in stopping the reproduction of the virus.
Under normal conditions interferon is not made rapidly enough, or in high enough concentrations to prevent HIV infection. HIV infection then becomes permanent and impossible to eradicate. Antibodies present in uninfected people allow interferon to be made quickly and in the high amounts capable of preventing permanent infection.
The natural antibody identified by Lum and Green may help explain how some people avoid HIV infection while others do not. Only 1 in 1,000 or 2,000 episodes of unprotected heterosexual intercourse results in infection, which leads the researchers to believe that people with high antibodies levels, may be protected; while those with low antibodies are not.
“These findings are not a vaccine for HIV, but allow the research community to understand more about the immune system and how it responds differently in those who naturally produce the antibody,” said lead investigator Dr. Jon Green, with VA Northern California Health Care System. “Future research will need to be done to understand if enhancing antibody protects against infection.”
This is the first known study of potentially protective antibody against HIV in healthy uninfected people. The scientists collected blood samples for more than two years from patients in geographic areas with high (Thailand) and low (USA) risks of HIV-infection. The findings suggest that ‘anti-HIV’ antibodies are a universal part of the human immune response. Scientists speculate that future research will study a person’s natural immunity and production anti-HIV antibodies to understand how to terminate HIV before the onset of infection.
“Additional studies are needed to determine if natural antibody protects against infection, what antibody levels are protective and why it is present in people without infection. Future research will be needed to determine if naturally occurring interferon- promoting antibody can be used to develop an effective HIV vaccine,” said Green.
The researchers are available for interview. If you would like more information regarding this discovery, please contact Tara Ricks, Public Affairs Officer, at (916) 843-9247 or e-mail Tara.Ricks@va.gov.