title: Lentivector integration sites in ependymal cells from a model of metachromatic leukodystrophy: non-B DNA as a new factor influencing integration.
abstract: The blood-brain barrier controls the passage of molecules from the blood into the central nervous system (CNS) and is a major challenge for treatment of neurological diseases. Metachromatic leukodystrophy is a neurodegenerative lysosomal storage disease caused by loss of arylsulfatase A (ARSA) activity. Gene therapy via intraventricular injection of a lentiviral vector is a potential approach to rapidly and permanently deliver therapeutic levels of ARSA to the CNS. We present the distribution of integration sites of a lentiviral vector encoding human ARSA (LV-ARSA) in murine brain choroid plexus and ependymal cells, administered via a single intracranial injection into the CNS. LV-ARSA did not exhibit a strong preference for integration in or near actively transcribed genes, but exhibited a strong preference for integration in or near satellite DNA. We identified several genomic hotspots for LV-ARSA integration and identified a consensus target site sequence characterized by two G-quadruplex-forming motifs flanking the integration site. In addition, our analysis identified several other non-B DNA motifs as new factors that potentially influence lentivirus integration, including human immunodeficiency virus type-1 in human cells. Together, our data demonstrate a clinically favorable integration site profile in the murine brain and identify non-B DNA as a potential new host factor that influences lentiviral integration in murine and human cells.
authors.affiliation: Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Center for Human Immunology, Western University, London, Ontario, Canada.
authors.forename: Robert G
authors.initials: RG
authors.lastname: McAllister
authors.affiliation: Department of Biochemistry, Western University, London, Ontario, Canada.
authors.forename: Jiahui
authors.initials: J
authors.lastname: Liu
authors.affiliation: Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Center for Human Immunology, Western University, London, Ontario, Canada.
authors.forename: Matthew W
authors.initials: MW
authors.lastname: Woods
authors.affiliation: Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Center for Human Immunology, Western University, London, Ontario, Canada.
authors.forename: Sean K
authors.initials: SK
authors.lastname: Tom
authors.affiliation: 1] Department of Biochemistry, Western University, London, Ontario, Canada [2] Department of Pathology and Laboratory Medicine, Western University, London, Ontario, Canada [3] Department of Pediatrics, Western University, London, Ontario, Canada [4] Children's Health Research Institute, Western University, London, Ontario, Canada.
authors.forename: C Anthony
authors.initials: CA
authors.lastname: Rupar
authors.affiliation: Department of Microbiology and Immunology, Schulich School of Medicine and Dentistry, Center for Human Immunology, Western University, London, Ontario, Canada.
authors.forename: Stephen D
authors.initials: SD
authors.lastname: Barr