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Updated: Jun 27, 2026
06:10
Following Cell-fate in E. coli After Infection by Phage Lambda
Published on: October 14, 2011
Proteasome inhibitors enhance bacteriophage lambda (lambda) mediated gene transfer in mammalian cells
Ketna Volcy1, Stephen Dewhurst
1Department of Microbiology, University of Rochester School of Medicine and Dentistry, Rochester, NY 14642, USA.
Virology
|December 10, 2008
Summary
Bacteriophage lambda vectors can deliver genes into mammalian cells, but this is inefficient. Inhibiting proteasomes and lysosomal proteases boosts gene transfer efficiency by preventing phage destruction.
Area of Science:
- Molecular Biology
- Virology
- Gene Therapy
Background:
- Bacteriophage lambda vectors offer a method for transferring genetic material into mammalian cells.
- The efficiency of phage-mediated gene transfer into mammalian cells is currently limited.
- Understanding the intracellular fate of phage vectors is crucial for improving transduction efficiency.
Purpose of the Study:
- To identify the rate-limiting steps in bacteriophage lambda-mediated gene transfer into mammalian cells.
- To investigate the role of cellular degradation pathways in limiting phage vector efficiency.
- To explore pharmacological strategies for enhancing phage-mediated gene delivery.
Main Methods:
- Utilized a bacteriophage lambda vector engineered with a mammalian luciferase reporter gene.
- Quantitated gene transfer efficiency in mammalian cells under various conditions.
- Assessed the impact of pharmacologic inhibitors targeting cell uptake and degradation pathways, including lysosomal proteases, proteasomes, and endosome acidification.
Main Results:
- Lysosomal protease inhibitors and proteasome inhibitors significantly enhanced phage-mediated luciferase expression.
- Inhibition of endosome acidification did not affect gene transfer efficiency, indicating phage lambda's pH tolerance.
- These findings suggest intracellular degradation pathways limit phage vector transduction.
Conclusions:
- Bacteriophage lambda vectors can be pharmacologically enhanced for improved gene transfer efficiency in mammalian cells.
- The proteasome complex may function as a cellular defense mechanism against viral infections.
- Targeting intracellular degradation pathways holds promise for advancing phage-based gene therapy applications.
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