A rare group of HIV patients are able to naturally suppress the virus without taking any drugs, a new study suggests.
These individuals, called ‘elite controllers,’ are only believed to account for 0.5 percent of people who are infected.
Researchers found that, because of where these patients have the virus encoded in their DNA, the pathogen is unable to make copies of itself.
This keeps the virus below detectable levels, which makes it untransmissible.
The team, from the Ragon Institute of MGH, MIT and Harvard, says the findings provide evidence that these people have achieved a ‘functional cure’ and could lead to a cure for those dependent on drugs to keep the virus from spreading.
HIV patients known as ‘elite controllers’ have the virus integrated in parts of their DNA where there is little gene activity, which prevents the virus from being able to make copies of itself (file image)
In the US, more than 1.2 million people are infected with HIV, the virus that leads to the potentially deadly disease AIDS. About 36,000 new infections were diagnosed last year.
Once a person contracts HIV, the virus sets about attacking and destroying immune cells that normally protect the body from infection.
In the last decade, doctors have gained a much improved understanding of how to control HIV.
The rate of deaths from the disease has plummeted since the peak of the AIDS epidemic in the early 1980s.
The Centers for Disease Control and Prevention recommend everyone between the ages of 13 and 64 be tested for HIV at least once.
Those who are at higher risk, including men who have sex with men or those who have a sexual partner who is HIV positive, should be tested as often as once a year or more.
Although HIV is treatable, the infection has no cure. Doctors recommend taking a combination or ‘cocktail’ of drugs known as antiretroviral therapy, or ART.
Within six months of taking the medication once a day, a person’s viral load will be virtually undetectable, but the body won’t be completely rid of it.
This is because the virus hides in the body by integrating its genetic material into DNA and forming what’s known as a latent reservoir.
ART isn’t able to destroy these reservoirs but if an HIV patient ceases taking the ‘cocktail’, the virus can start making copies of itself again.
Elite controllers have latent reservoirs, but they don’t need to take drugs to stop the virus from spreading throughout the body.
‘They naturally maintain what other people need ART to do,’ co-author Dr Mathias Lichterfeld, an infectious disease physician at Ragon, told HealthDay.
For the study, published in the journal Nature, the team looked at blood samples from 64 elite controllers and 41 HIV patients taking ART.
Results showed that, in elite controllers, HIV genetic material was found in so-called ‘gene deserts’ of the DNA.
These are where there is little gene activity so the virus cannot make copies of itself and instead remain in a ‘blocked and locked’ state.
‘This positioning of viral genomes in elite controllers is highly atypical, as in the vast majority of people living with HIV-1, HIV is located in the active human genes where viruses can be readily produced,’ said lead author Dr Xu Yu, an associate professor of Medicine at Harvard Medical School, in a statement.
Yu calls this a ‘functional cure,’ which occurs when a virus is still in the body but can be controlled without medication.
The researchers believe this is because, in the early days of infection, the immune systems of elite controllers killed the virus after it integrated into DNA regions with a great deal of gene activity.
The team says the findings could lead to a cure, either by creating drugs that replicate the phenomenon of elite controllers or that eliminate HIV that’s integrated in parts of the DNA that have substantial gene activity.