Noninvasive and targeted gene delivery into the brain using microbubble-facilitated focused ultrasound

PLoS One. 2013;8(2):e57682. doi: 10.1371/journal.pone.0057682. Epub 2013 Feb 27.

Abstract

Recombinant adeno-associated viral (rAAV) vectors are potentially powerful tools for gene therapy of CNS diseases, but their penetration into brain parenchyma is severely limited by the blood-brain barrier (BBB) and current delivery relies on invasive stereotactic injection. Here we evaluate the local, targeted delivery of rAAV vectors into the brains of mice by noninvasive, reversible, microbubble-facilitated focused ultrasound (FUS), resulting in BBB opening that can be monitored and controlled by magnetic resonance imaging (MRI). Using this method, we found that IV-administered AAV2-GFP (green fluorescence protein) with a low viral vector titer (1×10(9) vg/g) can successfully penetrate the BBB-opened brain regions to express GFP. We show that MRI monitoring of BBB-opening could serve as an indicator of the scale and distribution of AAV transduction. Transduction peaked at 3 weeks and neurons and astrocytes were affected. This novel, noninvasive delivery approach could significantly broaden the application of AAV-viral-vector-based genes for treatment of CNS diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Astrocytes / metabolism
  • Blood-Brain Barrier / metabolism
  • Blotting, Western
  • Brain / metabolism*
  • Contrast Media
  • Dependovirus / genetics
  • Fluorescent Antibody Technique
  • Gene Transfer Techniques*
  • Genetic Vectors / genetics
  • Green Fluorescent Proteins / metabolism
  • Magnetic Resonance Imaging
  • Male
  • Mice
  • Mice, Inbred ICR
  • Microbubbles*
  • Reproducibility of Results
  • Transduction, Genetic
  • Ultrasonics / methods*

Substances

  • Contrast Media
  • Green Fluorescent Proteins

Grants and funding

This study was supported by National Science Council (Taiwan) Grants NSC-100-2321-B-182-010. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.