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Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells
12:16

Porphyromonas gingivalis as a Model Organism for Assessing Interaction of Anaerobic Bacteria with Host Cells

Published on: December 17, 2015

Differential virulence and innate immune interactions of Type I and II fimbrial genotypes of Porphyromonas gingivalis

M Wang1, S Liang, K B Hosur

  • 1Department of Periodontics/Oral Health and Systemic Disease, University of Louisville School of Dentistry, Louisville, KY 40292, USA.

Oral Microbiology and Immunology
|October 17, 2009
PubMed
Abstract

Insights

Porphyromonas gingivalis fimbriae Type I causes more bone loss in periodontitis models than Type II. However, Type II fimbriae increase inflammation and invasion in macrophages.

Area of Science:

  • Microbiology
  • Immunology

Background:

  • Porphyromonas gingivalis fimbriae exhibit genetic diversity.
  • Type I fimbriae (Pg-I) are well-studied, while Type II (Pg-II) are prevalent in severe periodontitis.

Purpose of the Study:

  • Investigate virulence differences between P. gingivalis Type I and Type II fimbriae.
  • Assess the role of fimbriae in periodontitis and macrophage interactions.

Main Methods:

  • Compared P. gingivalis strains 33277 (Pg-I) and OMZ314 (Pg-II), reciprocal swap mutants, and FimA-deficient strains.
  • Utilized a mouse periodontitis model and mouse macrophage assays.

Main Results:

  • Strain 33277 (Pg-I) induced significantly more periodontal bone loss than OMZ314 (Pg-II).
  • Swapping fimbriae Type II for Type I in OMZ314 increased virulence.
  • Type II fimbriae enhanced proinflammatory and invasive macrophage activities.

Conclusions:

  • An inverse relationship exists between proinflammatory potential and experimental periodontitis.
  • Aggressive phenotypes may trigger host responses that hinder pathogen persistence.

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