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Phagocytosis and virulence of different strains of Porphyromonas gingivalis

G Sundqvist1, D Figdor, L Hänström

  • 1Department of Endodontics, University of Umeå, Sweden.

Scandinavian Journal of Dental Research
|April 1, 1991
PubMed

Insights

Porphyromonas gingivalis strains exhibit distinct characteristics impacting their interaction with human immune cells. Some strains resist phagocytosis, are hydrophobic, and possess a glycocalyx, but this doesn't always correlate with virulence in mice.

Area of Science:

  • Microbiology
  • Immunology
  • Pathogenesis

Background:

  • Porphyromonas gingivalis is an oral bacterium implicated in periodontal disease.
  • Understanding strain variation is crucial for comprehending P. gingivalis pathogenesis.

Purpose of the Study:

  • To investigate the in vitro and in vivo characteristics of Porphyromonas gingivalis strains.
  • To determine correlations between bacterial properties and virulence.

Main Methods:

  • Investigated 17 P. gingivalis strains for in vitro interaction with human polymorphonuclear leukocytes.
  • Assessed bacterial hydrophobicity, density, and virulence in a mouse model.
  • Utilized electron microscopy to examine bacterial surface structures.

Main Results:

  • P. gingivalis strains were categorized into two groups based on phagocytosis, hydrophobicity, and density.
  • Hydrophobic, high-density strains were readily phagocytosed; hydrophilic, low-density strains were poorly phagocytosed and exhibited a glycocalyx.
  • Two strains showed invasive pathogenicity in mice, while others caused localized abscesses.

Conclusions:

  • Bacterial hydrophobicity, density, and presence of a glycocalyx influence phagocytosis resistance.
  • Phagocytosis resistance does not directly correlate with the ability to cause invasive disease in a mouse model.
  • Further research is needed to elucidate the mechanisms of P. gingivalis virulence.

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