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Guiding epithelial cell phenotypes with engineered integrin-specific recombinant fibronectin fragments
Ashley C Brown1, Jessica A Rowe, Thomas H Barker
1The Wallace H. Coulter Department of Biomedical Engineering, Georgia Institute of Technology and Emory University, Atlanta, Georgia 30332-0535, USA.
Tissue Engineering. Part A
|August 11, 2010
Summary
The fibronectin synergy site, not just RGD, is crucial for regulating epithelial cell behavior. This finding is key for tissue engineering and understanding cell repair.
Area of Science:
- Biochemistry
- Cell Biology
- Tissue Engineering
Background:
- The extracellular matrix (ECM) guides cell behavior through cell-surface receptors like integrins.
- Fibronectin (Fn) contains specific sequences (synergy site and RGD) that influence cell phenotype, particularly during tissue repair.
Purpose of the Study:
- To investigate the role of the fibronectin synergy site in regulating epithelial cell phenotype.
- To determine if the synergy site directs integrin specificity and influences cell behavior.
Main Methods:
- Epithelial cells were cultured on fibronectin fragments with or without the synergy site.
- Phenotype was assessed via cytoskeleton changes, cell-cell contacts, gene expression (epithelial/mesenchymal markers), and wound healing assays.
Main Results:
- Epithelial cells binding RGD alone (without synergy) primarily used αv integrins.
- Cells on RGD-only fragments showed a mesenchymal shift, partly due to enhanced TGF-β signaling.
- The synergy site in fibronectin (FnIII9'10) maintained an epithelial phenotype.
Conclusions:
- The fibronectin synergy site is critical for maintaining epithelial cell phenotype and preventing mesenchymal transition.
- Integrin specificity, guided by ECM cues like the synergy site, is vital for directing cell behavior in tissue engineering.
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