AAV ablates neurogenesis in the adult murine hippocampus
Abstract
Recombinant adeno-associated virus (rAAV) has been widely used as a viral vector across mammalian biology and has been shown to be safe and effective in human gene therapy. We demonstrate that neural progenitor cells (NPCs) and immature dentate granule cells (DGCs) within the adult murine hippocampus are particularly sensitive to rAAV-induced cell death. Cell loss is dose dependent and nearly complete at experimentally relevant viral titers. rAAV-induced cell death is rapid and persistent, with loss of BrdU-labeled cells within 18 hours post-injection and no evidence of recovery of adult neurogenesis at 3 months post-injection. The remaining mature DGCs appear hyperactive 4 weeks post-injection based on immediate early gene expression, consistent with previous studies investigating the effects of attenuating adult neurogenesis. In vitro application of AAV or electroporation of AAV2 inverted terminal repeats (ITRs) is sufficient to induce cell death. Efficient transduction of the dentate gyrus (DG)-without ablating adult neurogenesis-can be achieved by injection of rAAV2-retro serotyped virus into CA3. rAAV2-retro results in efficient retrograde labeling of mature DGCs and permits in vivo 2-photon calcium imaging of dentate activity while leaving adult neurogenesis intact. These findings expand on recent reports implicating rAAV-linked toxicity in stem cells and other cell types and suggest that future work using rAAV as an experimental tool in the DG and as a gene therapy for diseases of the central nervous system (CNS) should be carefully evaluated.
Data availability
All data generated or analysed during this study are included in the manuscript and supporting files. Source data files have been provided for all figures and supplemental figure
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Author details
Funding
National Institutes of Health (R01 AG056306)
- Fred H Gage
National Institutes of Health (R01 MH114030)
- Fred H Gage
National Institutes of Health (K08 NS093130)
- Matthew Shtrahman
McKnight Endowment Fund for Neuroscience
- Fred H Gage
- Matthew Shtrahman
National Institutes of Health (S10OD025060)
- Matthew Shtrahman
James S. McDonnell Foundation
- Fred H Gage
Leona M. and Harry B. Helmsley Charitable Trust
- Fred H Gage
Ray and Dagmar Dolby Family Fund
- Fred H Gage
Dan and Martina Lewis (Biophotonics Fellows Program)
- Stephen Johnston
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Animal experimentation: This study was performed in strict accordance with the recommendations in the Guide for the Care and Use of Laboratory Animals of the National Institutes of Health. All of the animals were handled according to approved institutional animal care and use committee (IACUC) protocols (S12201) of the University of California, San Diego. All surgery was performed under isoflurane anesthesia, and every effort was made to minimize suffering
Copyright
© 2021, Johnston et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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