Researchers from the Lewis Katz School of Medicine at Temple University and the University of Pittsburgh show that HIV-1 infections can be eliminated from the genomes of living animals. Findings from the study have been published in the journal Molecular Therapy. Genetic Engineering and Biotechnology News reports: This is the first study to demonstrate that HIV-1 replication can be completely shut down and the virus eliminated from infected cells in animals with a powerful gene-editing technology known as CRISPR/Cas9. The new work builds on a previous proof-of-concept study that the team published in 2016, in which they used transgenic rat and mouse models with HIV-1 DNA incorporated into the genome of every tissue of the animals' bodies. They demonstrated that their strategy could delete the targeted fragments of HIV-1 from the genome in most tissues in the experimental animals. In this new study, the LKSOM team genetically inactivated HIV-1 in transgenic mice, reducing the RNA expression of viral genes by roughly 60% to 95% -- confirming their earlier findings. They then tested their system in mice acutely infected with EcoHIV, the mouse equivalent of human HIV-1. In the third animal model, a latent HIV-1 infection was recapitulated in humanized mice engrafted with human immune cells, including T cells, followed by HIV-1 infection. "These animals carry latent HIV in the genomes of human T cells, where the virus can escape detection," Dr. Hu explained. Amazingly, after a single treatment with CRISPR/Cas9, viral fragments were successfully excised from latently infected human cells embedded in mouse tissues and organs.