A new study has suggested that the rapid evolution of HIV might, in fact, be a good thing. As the virus has reshaped itself to grow resistant to the immune system of the infected patients, it has also become less capable of causing AIDS. As a consequence, those carrying the virus in their systems develop AIDS at a slower rate. HIV has thus been shown to become less virulent. Similar positive effects have been shown with greater access to antiretroviral therapy (ART).
It seems that the ability of the virus to be promote to resistant forms has taken its toll on itself. The virus is suspected to be less virulent as people infected with it are developing AIDS slower. The scientific paper that attests to such is published in the journal Proceedings of the National Academy of Sciences (PNAS).
Participants of the research – 2000 women with chronic HIV infection – were sampled from two African countries that have been affected to a terribly large extent by the pandemic, Botswana and South Africa.
The scientists looked into the interaction between the body’s natural immune system and HIV: do the body’s responses to the virus make the latter less virulent? The observations stemming from the experiments showed that patients having a gene that expresses a certain protein develop AIDS at a slower pace than those who are not endowed with the gene in question. The protein that is expressed is the HLA-B*57; it provides a shielding effect from HIV. The subjects from Botswana no more benefited from the protective effect of the gene because HIV has evolved to adapt to the HLA-B*57 protein. This was more pronounced in Botswana than in South Africa. However, this is not necessarily good for the virus. The processes it went through to adapt to the protective protein has a certain cost. Unfortunately for the virus, this has decreased its capacity to replicate; fortunately for us, the virus has been shown to become less virulent.
Viral adaptation to gene variants is reducing the virulence of the deadly HIV. As a result, this is contributing positively to the elimination of HIV.
The study also put into perspective the effect of ART on HIV virulence. Selective treatment of people has demonstrated that HIV variants will evolve at a faster rate, but, at the same time, driving down its replication capacity.
One of the authors stated that:
“This research highlights the fact that HIV adaptation to the most effective immune responses we can make against it comes at a significant cost to its ability to replicate. Anything we can do to increase the pressure on HIV in this way may allow scientists to reduce the destructive power of HIV over time.“
Another commented on the second aspect of the study, dealing with ART:
“The widespread use of ART is an important step towards the control of HIV. This research is a good example of how further research into HIV and drug resistance can help scientists to eliminate HIV.”