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Updated: Jul 31, 2026
08:39
Stereotaxic Injection of a Viral Vector for Conditional Gene Manipulation in the Mouse Spinal Cord
Published on: March 18, 2013
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Viral and cellular insulators promote sustained HSV vector-mediated transgene expression in brain
Selene Ingusci1, Justus B Cohen1, Joseph C Glorioso1
1Department of Microbiology and Molecular Genetics, University of Pittsburgh School of Medicine, Pittsburgh, PA 15219, USA.
Summary
Researchers enhanced gene therapy using herpes simplex virus type 1 (HSV-1) vectors by optimizing DNA insulator elements. This improved long-term transgene expression in neurons, offering potential for treating brain disorders.
Area of Science:
- Neuroscience
- Molecular Biology
- Gene Therapy
Background:
- Gene therapy platforms utilize replication-defective herpes simplex virus type 1 (HSV-1) vectors.
- Maintaining transgene expression requires overcoming host epigenetic silencing using DNA insulators.
- Previous strategies involved strategic placement of viral insulators near specific HSV-1 genes.
Purpose of the Study:
- To develop an enhanced gene therapy vector with sustained transgene expression in neurons.
- To investigate the efficacy of a novel insulator design combining cellular and viral elements.
- To assess the long-term expression levels and duration in the brain.
Main Methods:
- Developed replication-defective HSV-1 vectors with transgene cassettes replacing viral genes (LAT or ICP4).
- Evaluated transgene expression in neuronal cells in vitro and following in vivo brain delivery.
- Designed and tested a novel insulator cassette combining cellular and viral insulator elements.
Main Results:
- The ICP4 locus demonstrated higher transgene expression permissiveness than the LAT locus in vitro.
- Transgene expression from both loci lasted at least 4 months in vivo, but declined over time.
- The novel insulator design significantly enhanced transgene expression levels and duration (at least 11.7 months) compared to viral insulators alone.
Conclusions:
- A novel insulator cassette combining cellular and viral elements enhances long-term transgene expression in neurons.
- This improved gene therapy vector platform shows promise for treating neurological and brain disorders.
- Optimized insulator strategies are critical for effective in vivo gene therapy applications.
Keywords:
CNS stable long-term expressiongene expressiongene therapyinsulator elementsreplication-defective HSV vectorsMore Related Videos
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