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Updated: May 13, 2026
12:02
Studying Cell Cycle-regulated Gene Expression by Two Complementary Cell Synchronization Protocols
Published on: June 6, 2017
Polyplex exposure inhibits cell cycle, increases inflammatory response, and can cause protein expression without cell
Rebecca L Matz1, Blake Erickson, Sriram Vaidyanathan
1Department of Chemistry, University of Michigan, Ann Arbor, Michigan 48109, USA.
Molecular Pharmaceutics
|March 6, 2013
Summary
Poly(ethylenimine) (PEI)-based polyplexes enable cell division-independent protein expression. PEI polyplexes also slow cell division and activate inflammatory pathways, revealing a novel gene delivery mechanism.
Area of Science:
- Biotechnology
- Cell Biology
- Molecular Biology
Background:
- Poly(ethylenimine) (PEI)-based polyplexes are commonly used for gene delivery.
- The relationship between cell division and transgene expression is not fully understood.
- Previous hypotheses suggested protein expression requires cell mitosis.
Purpose of the Study:
- To evaluate the relationship between cell division and protein expression using PEI-based polyplexes.
- To investigate the impact of PEI polyplexes on cell cycle progression.
- To explore the inflammatory response induced by PEI polyplexes.
Main Methods:
- Utilized PKH26 membrane dye to assess cell division.
- Employed cyan fluorescent protein (CFP) to monitor protein expression.
- Analyzed gene expression arrays in polyplex-exposed cells.
Main Results:
- Observed significant protein expression in non-dividing cells, challenging the mitosis-dependent hypothesis.
- PEI polyplex exposure approximately halved cell doubling time.
- Gene expression analysis revealed cell cycle arrest, downregulation of mitosis-related genes, and upregulation of inflammatory and chemokine pathways.
Conclusions:
- A cell division-independent pathway for protein expression exists with PEI polyplexes.
- PEI polyplexes impede cell division and elicit an inflammatory response.
- Findings suggest a need to reconsider current models of gene delivery via PEI polyplexes.
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