An article in WebMD reported that some people have immune systems that seem to help them when infected with HIV. It appears that one percent of HIV-infected persons have a second line of immune defense, which backs up the body’s defenses that HIV destroys. These people are called “controllers,” and they can maintain long-term control of HIV without daily antiretrovirals because of the immune protein called A3, which stops the virus from spreading.
Researchers from Northwestern University analyzed the cells of controllers and found they had a greater number of A3 protein in certain white blood cells called “resting memory T cells.” A3 rendered new virus made from the resting memory T cells harmless, leaving them incapable of infecting other cells. Unlike other cells that could not recognize HIV when it mutated, A3 was part of the intrinsic immune system that was not fooled by the virus. According to Dr. Richard D’Aquila, director of the university’s HIV Translational Research Center and senior author of the study, the intrinsic immune system recognizes the HIV nucleic acids, which it cannot change, and damages them.
The researchers suggest that treatment with anti-HIV drugs soon after becoming infected could help individuals control HIV without constant medication by preserving their A3 reserves. They contend that not treating the virus for several months depletes these reserves. The researchers are working to create a drug that would boost the A3 protein.
The full report, “Lower HIV Provirus Levels Are Associated with More APOBEC3G Protein in Blood Resting Memory CD4+ T Lymphocytes of Controllers In Vivo,” was published online in the journal PLoS ONE (2013; 8(10): e76002, doi:10.1371/journal.pone.0076002).