(TMU) — Nearly 37 million people across the world are infected with HIV, with nearly 5,000 additional people being infected on a daily basis. And while expensive anti-retroviral therapy (ART) is capable of suppressing the replication of the virus to the point where it’s undetectable in the blood, lifelong usage of the drugs is required or the HIV infection can come back and progress toward full-blown AIDS.
However, researchers at Temple University in Philadelphia and the University of Nebraska Medical Center (UNMC) have successfully managed to eliminate HIV from infected mice in an important advance against developing a potential cure for those who infected by the life-threatening virus.
The achievement marks the first time that the AIDS-causing virus has been completely eradicated from the genomes of a living creature, according to the study published July 2 in the journal Nature Communications.
Kamel Khalili, co-senior author of the study and director of Temple’s neurovirology center and its neuroAIDS center, said:
“Our study shows that treatment to suppress HIV replication and gene editing therapy, when given sequentially, can eliminate HIV from cells and organs of infected animals.”
In the study involving 29 mice, researchers used the gene-editing system CRISPR-Cas9 to splice out HIV DNA from the infected cells of mice alongside a new drug regimen called long-acting slow-effective release anti-retroviral therapy, or LASER ART.
LASER ART is an important step forward because it encases HIV antiretroviral drugs in nanocrystals that then travel to those tissues where HIV is lying dormant. The nanocrystals are stashed away within cells for weeks as the drugs are slowly released, decreasing the need for constant ART administration. The new LASER ART system had already shown promise in animal studies as an efficient treatment for HIV.
The mice that were infected with HIV were first given LASER ART treatment before the researchers proceeded to the CRISPR gene editing stage. After the one-two punch, nearly forty percent of the mice showed no sign of the virus, according to the team.
However, when mice were only treated to either LASER ART therapy or CRISPR gene editing, the results showed “viral rebound in 100% of treated infected animals.”
Khalili explained to TIME magazine:
“Over the years, we have looked at HIV as an infectious disease. But once it gets into the cell, it’s no longer an infectious disease but becomes a genetic disease because the viral genome is incorporated into the host genome.
In order to cure the disease, we need a genetic strategy. Gene editing gives us the opportunity to eliminate viral DNA from host chromosomes without hurting the host genome.”
In a university news release, Khalili said:
“The big message of this work is that it takes both CRISPR-Cas9 and virus suppression through a method such as LASER ART, administered together, to produce a cure for HIV infection.”
The professor added:
“We now have a clear path to move ahead to trials in nonhuman primates and possibly clinical trials in human patients within the year.”
Other researchers are thrilled by the results but remain eager for further answers. Virologist Jonathan Stoye of the Francis Crick Institute in London wasn’t involved with the study but is curious as to why the treatment only worked on 40 percent of the mice. However, he acknowledged in a statement that the team’s study “is a tremendously exciting paper offering a vision of a potential path to a permanent cure to AIDS in the future.”