Taking a major step forward in HIV research, scientists at the Lewis Katz School of Medicine at Temple University have successfully edited SIV – a virus closely related to HIV, the cause of AIDS – from the genomes of non-human primates. The breakthrough brings Temple researchers and their collaborators closer than ever to developing a cure for human HIV infection.
“We show for the first time that a single inoculation of our CRISPR gene-editing construct, carried by an adeno-associated virus, can edit out the SIV genome from infected cells in rhesus macaque monkeys,” said 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 (LKSOM).
Dr. Khalili was a senior co-investigator on the new study, with Tricia H. Burdo, PhD, Associate Professor and Associate Chair of Education in the Department of Neuroscience at LKSOM, who is an expert on the utilization of the SIV (simian immunodeficiency virus)-infected antiretroviral therapy (ART)-treated rhesus macaque model for HIV pathogenesis and cure studies; and with Andrew G. MacLean, PhD, Associate Professor at the Tulane National Primate Research Center and the Department of Microbiology and Immunology at Tulane University School of Medicine, and Binhua Ling, PhD, Associate Professor at the Southwest National Primate Research Center, Texas Biomedical Research Institute. Dr. Ling was previously Associate Professor at the Tulane National Primate Research Center and the Department of Microbiology and Immunology at Tulane University School of Medicine. Pietro Mancuso, PhD, an Assistant Scientist in Dr. Khalili's laboratory in the Department of Neuroscience at LKSOM, was first author on the report, which was published online November 27 in the journal Nature Communications.
Of particular significance, the new work shows that the gene-editing construct developed by Dr. Khalili's team can reach infected cells and tissues known to be viral reservoirs for SIV and HIV. These reservoirs, which are cells and tissues where the viruses integrate into host DNA and hide away for years, are a major barrier to curing infection. SIV or HIV in these reservoirs lies beyond the reach of ART, which suppresses viral replication and clears the virus from the blood. As soon as ART is stopped, the viruses emerge from their reservoirs and renew replication.
In non-human primates, SIV behaves very much like HIV. “The SIV-infected rhesus macaque model studied in Dr. Burdo's lab is an ideal large animal model for recapitulating HIV infection in humans,” explained Dr. Khalili.