Like many viruses, HIV has evolved to become resistant to genes that provide natural immunity in the human body. But a new study finds that this evolution may be the virus’ downfall; it is also curbing its ability to cause AIDS.

Share on Pinterest As HIV evolves to adapt to the human immune system, its virulence may be slowing.

The research team – led by Prof. Phillip Goulder of the University of Oxford in the UK – also found that an increase in access to antiretroviral therapy (ART) has meant that progression to AIDS among people with HIV is slowing.

The researchers say their findings – recently published in the Proceedings of the National Academy of Sciences (PNAS) – bring us one step closer to tackling the HIV pandemic that is responsible for around 39 million deaths worldwide.

Prof. Goulder and his team enrolled more than 2,000 women with chronic HIV to the study. The women were from two countries worst hit by the HIV epidemic – South Africa and Botswana.

First, the researchers set out to see how the body’s natural immune response impacts the virulence of HIV, or its ability to progress to AIDS.

In particular, the team investigated blood proteins called human leukocyte antigens (HLA). These proteins allow the immune system to distinguish between friendly and harmful proteins. The researchers explain that some people have a gene that expresses a protein called HLA-B*57, which is known to have a “protective effect” against HIV.

The researchers found, however, that in some cases HIV has evolved to become resistant to the protective effects of HLA-B*57 – particularly among women in Botswana. But they also found that this evolution has impaired the ability of HIV to replicate, meaning its progression to AIDS is being slowed.

According to the researchers, the way HIV is evolving to resist protective gene variants is hampering the virulence of transmitted HIV. This means that HIV is playing a part in its own eradication.

Commenting on this finding, Prof. Goulder says: