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Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells
Published on: December 17, 2015
Porphyromonas gingivalis fimbriae
Morten Enersen1, Kazuhiko Nakano, Atsuo Amano
1Institute of Oral Biology, Faculty of Dentistry, University of Oslo, Oslo, Norway.
Journal of Oral Microbiology
|May 14, 2013
Summary
Virulent clones of Porphyromonas gingivalis, particularly those with specific long fimbriae types, may drive aggressive periodontitis. Fimbriae variations influence bacterial adhesion, invasion, and host cytokine response, impacting disease severity.
Area of Science:
- Oral microbiology
- Periodontology
- Bacterial pathogenesis
Background:
- Marginal periodontitis is a complex disease influenced by host susceptibility and microbial virulence.
- Porphyromonas gingivalis is a key periodontal pathogen with diverse virulence factors, including fimbriae.
- Clonal heterogeneity in virulence may explain varying disease severity.
Purpose of the Study:
- To investigate the role of clonal diversity and fimbriae variations in Porphyromonas gingivalis pathogenesis.
- To explore the differential virulence of P. gingivalis fimA types in periodontitis.
Main Methods:
- Analysis of Porphyromonas gingivalis clonal heterogeneity.
- Characterization of long and short fimbriae expression and function.
- Assessment of bacterial adhesion, invasion, and host cytokine induction.
Main Results:
- Long fimbriae of P. gingivalis exhibit clonal diversity (fimA types I-V, Ib).
- Type II fimA clones show enhanced adhesion and invasion compared to other types.
- Both long and short fimbriae contribute to cytokine expression (IL-1α, IL-β, IL-6, TNF-α) and alveolar bone resorption.
Conclusions:
- Specific virulent clones of P. gingivalis, particularly those with type II fimA, may drive aggressive periodontitis.
- Fimbriae variations in P. gingivalis are critical virulence factors influencing disease development and severity.
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