Scientists remove HIV virus in animals using gene editing

According to the Centers for Disease Control and Prevention (CDC), more than 36 million people across the world are HIV positive.

Presently there is no cure for HIV, researchers used gene editing technology called "CRISPR/Cas9 to excised the HIV-1 provirus in three animal models.

A provirus is an inactive form of virus. It occurs when the virus has integrated into the genes of a cell. In the case of HIV, these host cells are the so-called CD4 cells - once the virus has been incorporated into the DNA of the CD4 cells, it replicates itself with each generation of CD4 cells.

The three mouse models used in the research are: a "humanized" model, in which the mice were genetically modified to have human immune cells, which were then infected with HIV-1.

The team was co-led by Dr. Wenhui Hu, Ph.D., associate professor in the Center for Metabolic Disease Research and the Department of Pathology at the Lewis Katz School of Medicine (LKSOM) at Temple University in Philadelphia, together with Kamel Khalili, Ph.D., Laura H. Carnell Professor and chair of the Department of Neuroscience at LKSOM, and Won-Bin Young, Ph.D, who just recently joined LKSOM.

Gene editing strategy is 96 percent effective. Dr. Hi and team inactivated HIV-1, significantly reducing the RNA expression of viral genes in the organs and tissues of genetically modified mice.

Specifically, the RNA expression was reduced by approximately 60 to 95 percent. Researchers tested their result
 by acutely infecting mice with EcoHIV - the equivalent of the HIV-1 in humans.

The third model, mice received a transplant of human immune cells, including T cells, which were then infected with HIV-1.
One of the main reasons that a cure for HIV has yet to be discovered is the virus's ability to "hide" in the genomes of T cells, where it lives latently. This is why researchers applied the CRISPR/Cas9 technology to these mice with infected T cells.