Clade F AAVHSCs cross the blood brain barrier and transduce the central nervous system in addition to peripheral tissues following intravenous administration in nonhuman primates

PLoS One. 2019 Nov 26;14(11):e0225582. doi: 10.1371/journal.pone.0225582. eCollection 2019.

Abstract

The biodistribution of AAVHSC7, AAVHSC15, and AAVHSC17 following systemic delivery was assessed in cynomolgus macaques (Macaca fascicularis). Animals received a single intravenous (IV) injection of a self-complementary AAVHSC-enhanced green fluorescent protein (eGFP) vector and tissues were harvested at two weeks post-dose for anti-eGFP immunohistochemistry and vector genome analyses. IV delivery of AAVHSC vectors produced widespread distribution of eGFP staining in glial cells throughout the central nervous system, with the highest levels seen in the pons and lateral geniculate nuclei (LGN). eGFP-positive neurons were also observed throughout the central and peripheral nervous systems for all three AAVHSC vectors including brain, spinal cord, and dorsal root ganglia (DRG) with staining evident in neuronal cell bodies, axons and dendritic arborizations. Co-labeling of sections from brain, spinal cord, and DRG with anti-eGFP antibodies and cell-specific markers confirmed eGFP-staining in neurons and glia, including protoplasmic and fibrous astrocytes and oligodendrocytes. For all capsids tested, 50 to 70% of glial cells (S100-β+) and on average 8% of neurons (NeuroTrace+) in the LGN were positive for eGFP expression. In the DRG, 45 to 62% of neurons and 8 to 12% of satellite cells were eGFP-positive for the capsids tested. eGFP staining was also observed in peripheral tissues with abundant staining in hepatocytes, skeletal- and cardio-myocytes and in acinar cells of the pancreas. Biodistribution of AAVHSC vector genomes in the central and peripheral organs generally correlated with eGFP staining and were highest in the liver for all AAVHSC vectors tested. These data demonstrate that AAVHSCs have broad tissue tropism and cross the blood-nerve and blood-brain-barriers following systemic delivery in nonhuman primates, making them suitable gene editing or gene transfer vectors for therapeutic application in human genetic diseases.

MeSH terms

  • Administration, Intravenous
  • Animals
  • Blood-Brain Barrier / metabolism*
  • Central Nervous System / metabolism*
  • Dependovirus / genetics*
  • Ganglia, Spinal / metabolism
  • Genetic Therapy / methods
  • Genetic Vectors / metabolism*
  • Green Fluorescent Proteins / genetics
  • Green Fluorescent Proteins / immunology
  • Green Fluorescent Proteins / metabolism
  • HEK293 Cells
  • Humans
  • Immunohistochemistry
  • Macaca
  • Neuroglia / metabolism
  • Neurons / metabolism
  • Tissue Distribution

Substances

  • enhanced green fluorescent protein
  • Green Fluorescent Proteins

Grants and funding

The work described in this manuscript was funded in its entirety by Homology Medicines, Inc. The funder provided support in the form of salaries for authors [JLE, JG, LJS, HR, TAS, KP, NZ, KO, MO, AS], but did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. The specific roles of these authors are articulated in the ‘author contributions’ section. EC is an employee of and received salary support from Premier Laboratory, LLC and performed immunohistochemistry under contract with Homology Medicines, Inc. Premier Laboratory, LLC did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript. PM is an employee of and received salary support from The Mannheimer Foundation, Inc. and performed the in-life biodistribution studies in nonhuman primates under contract with Homology Medicines, Inc. The Mannheimer Foundation did not have any additional role in the study design, data collection and analysis, decision to publish, or preparation of the manuscript.