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Updated: Jul 12, 2026
05:57
In Vitro Assay of Bacterial Adhesion onto Mammalian Epithelial Cells
Published on: May 16, 2011
Bacterial binding to extracellular matrix proteins -- in vitro adhesion
C Schou1, T C Bøg-Hansen, N E Fiehn
1Institute of Odontology, Faculty of Health Sciences, University of Copenhagen, Denmark.
Summary
Oral streptococcus binding to human proteins like fibronectin and laminin varied based on bacterial growth media. Surface hydrophobicity correlated with binding strength, suggesting lectin-like and protein-based interactions.
Area of Science:
- Microbiology
- Biochemistry
- Oral Health Research
Background:
- Oral streptococci are key players in dental plaque formation and biofilm development.
- Bacterial adhesion to host extracellular matrix proteins is a critical step in colonization.
- Understanding these interactions is vital for developing strategies to prevent oral diseases.
Purpose of the Study:
- To investigate the binding capabilities of oral streptococcus to various immobilized human extracellular matrix proteins.
- To determine the influence of bacterial growth media on protein-binding profiles.
- To elucidate the mechanisms underlying streptococcal adhesion to these proteins.
Main Methods:
- Development of a binding assay to quantify oral streptococcus adherence to immobilized fibronectin, laminin, vitronectin, fibrinogen, collagen IV, and heparin.
- Cultivation of oral streptococcus strains in different growth broths (Brain Heart Infusion, Trypticase Soy, Todd-Hewitt, DMEM).
- Correlation analysis between measured bacterial surface hydrophobicity and protein binding strength; assessment of binding inhibition using specific agents.
Main Results:
- Oral streptococci demonstrated significant binding to immobilized fibronectin and laminin, with moderate binding to vitronectin.
- No significant binding was observed on fibrinogen, collagen IV, or heparin.
- Bacterial protein binding was significantly influenced by the composition of the growth medium.
- A strong positive correlation was found between bacterial surface hydrophobicity and the strength of protein binding.
- Inhibition studies suggested the involvement of both lectin-like and protein-based binding mechanisms, potentially mediated by protein receptors.
Conclusions:
- Oral streptococcal adherence to host proteins is specific and influenced by growth conditions.
- Surface hydrophobicity is a key factor mediating streptococcal interactions with fibronectin and laminin.
- Multiple molecular mechanisms, including lectin-like and protein-receptor interactions, contribute to oral streptococcus adhesion.
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