PHILADELPHIA, March 21 (UPI) -- Scientists edited HIV-1 DNA out of the genome of human immune cells, preventing virus replication and reinfection of the cleared cells.
Using the CRISPR/Cas9 gene editing technique, scientists at Temple University eliminated HIV-1 DNA from T cell genomes in lab experiments, and prevented reinfection after the cells were re-exposed to the virus, they report in a study published in Nature: Scientific Reports.
The CRISPR/Cas9 gene editing method uses RNA proteins to alter targeted sections of DNA in a cell. Previously, scientists at Temple had edited HIV DNA out of human cell lines. The new study, using patient cells grown in the lab, showed cleared cells were no longer susceptible to infection by HIV.
Dr. Kamel Khalili, director of the Comprehensive NeuroAIDS Center at Temple University and a researcher involved with the study, said while antiretroviral drugs can help control HIV infection, once patients stop taking them, the virus starts replicating again from copies of its DNA in other cells.
"The findings are important on multiple levels," Khalili said in a press release. "They demonstrate the effectiveness of our gene editing system in eliminating HIV from the DNA of CD4 T-cells and, by introducing mutations into the viral genome, permanently inactivating its replication. Further, they show that the system can protect cells from reinfection and that the technology is safe for the cells, with no toxic effects."
The scientists edited out the HIV-1 proviral DNA in T-cell genomes of human cell lines using CRISPR, finding the cells were protected from reinfection by other, unedited cells.
Using T-cells from HIV patients grown in cell culture, the scientists reported using the gene editing method lowered viral load in the patient's cells, suggesting it could be used as a treatment.
"These experiments had not been performed previously to this extent," Khalili said "But the questions they address are critical, and the results allow us to move ahead with this technology."