Researchers Use Gene Editing to Remove HIV-1 From CD4+ T-Cells

Researchers have designed a special gene editing system that has removed HIV from cultured human cells, according to a study published in the Nature journal, Scientific Reports.

Senior researcher Kamel Khalili, PhD, Laura H. Carnell Professor and Chair of the Department of Neuroscience, Director of the Center for Neurovirology, and Director of the Comprehensive NeuroAIDS Center at the Lewis Katz School of Medicine at Temple University and colleagues targeted HIV-1 proviral DNA with guide RNA (gRNA) and a nuclease enzyme, Cas9 using a system known as CRISPR.

The Cas9/gRNA complex finds the virus in the genome of the CD4+ T-cells and severs the strands of DNA to remove HIV.

In an interview with Infectious Disease Advisor, Dr Khalili said, “Our new data show that the CRISPR system can eliminate the integrated HIV genome from latently infected T cells, that CRISPR/Cas9 can suppress acute infection of T cells with HIV, and by introducing mutations in HIV DNA in patient T cells, CRISPR/Cas9 decreases viral replication and expression of viral proteins in ex vivo studies.”

In addition to removing the virus, the study showed that cells are also protected from becoming reinfected. Ex vivo experiments revealed that gene editing also greatly reduced viral load and suppressed replication of the virus.

Using a method called ultra-deep genome sequencing, Dr Khalili and colleagues examined possible toxicity and other negative effects of gene editing and found no negative consequences from the process.

“Gene editing is a potent strategy that can be developed as a therapeutic tool for permanently stopping replication of the virus and can also be utilized as a prophylactic tool for protecting cells against viral infection,” Dr Khalili told Infectious Disease Advisor.  “This genetic strategy will need to be further developed in order to be brought to the clinic in upcoming years.”

The technique could have widespread application, the researchers explained. “Gene editing offers a powerful tool that will revolutionize the treatment of infectious diseases, as well as others including genetic disorders and cancer.” Dr Khalili concluded in the interview.

Reference

1.     Kaminski R, Chen Y, Fischer T et al. Elimination of HIV-1 genomes from human T-lymphoid cells by CRISPR/Cas9 gene editing. Sci Rep. 2016; 6:(22555). doi:10.1038/srep22555. Published March 4, 2016. Accessed March 29, 2016.