Some HIV patients hold secret to cure in their genes
Scientists pick up clues from patients who can control the virus by themselves
Alandmark study has found that some people can control their HIV without requiring medication . The protection occurs when “ viral reservoirs ” in their genes can ’ t be reactivated following an attack from the immune system .
Researchers from the Ragon Institute in Boston found that these virus pockets help so-called elite controllers maintain spontaneous , drug-free control of their HIV . The discovery is helping researchers move closer to finding a cure for HIV infection .
For years , the team has been looking at how a tiny number of people — about 0.5 percent of HIV patients globally — is able to fight off the virus naturally .
Their immune systems use a T-cell mediated immune response to control the virus without medication to the point that the virus is completely undetectable by standard testing .
The researchers believe the interplay between elite controllers ’ immune systems and HIV may hold the key to helping the immune systems of people living with the virus to suppress it without daily treatment , achieving what is known as a functional cure .
HIV affects more than 35 million people worldwide and can be effectively controlled , though not cured , with a daily regimen of antiretroviral drugs ( ART ). Upon infection , retroviruses like HIV place copies of their viral genetic material into the genomes of cells , creating viral reservoirs or sanctuaries where HIV persists despite ART throughout the body .
When a complete copy of the virus , or intact viral genome , is incorporated into a cell ’ s genome , it can be used to create new copies of HIV . For people living with HIV , this means that if they stop taking ART , the intact viral genomes previously integrated into the cells ’ genomes start making new copies of the virus , leading to a rapid viral rebound and disease progression . The HIV viral reservoir has been a major obstacle to finding an HIV cure .
“ HIV is able to cause incurable disease because it can insert its genetic material into the human genome and persist there indefinitely . It has previously been very difficult to map the location of replication-competent HIV within the human genome , but using a new , highly sensitive , nextgeneration sequencing assay we were able to do just that using patients with natural control of the infection ,” Dr Kevin Einkauf , a researcher at the institute , told Global Health Asia-Pacific .
“ Using this technology , it was surprising that the virus in elite controllers was integrated into part of the genome that are gene deserts . These areas are quite condensed and acquiescent , and because they integrate into these regions , HIV cannot replicate itself and create virus particles anymore ,” he added .
If scientists are able to identify which viral reservoirs can make new copies of the virus after treatment stops , it may help them target a treatment against the active , or reboundcompetent , reservoirs .
Once the kind of T-cell immunity that is present in elite controllers can be activated in others , it may be possible to eliminate rebound-competent viral reservoirs in people living with HIV to achieve a functional cure , the Ragon team hopes .
GlobalHealthAsiaPacific . com NOVEMBER 2020
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