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09:47

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Published on: July 2, 2013

Molecular mediators of Porphyromonas gingivalis-induced T-cell apoptosis

J I Harris1, R R B Russell, M A Curtis

  • 1Department of Oral Biology, The Dental School, University of Newcastle upon Tyne, Newcastle upon Tyne, UK.

Oral Microbiology and Immunology
|July 18, 2002
PubMed

Insights

Porphyromonas gingivalis culture supernatants induce T-cell apoptosis by increasing histone H4 acetylation, independent of proteases. This finding sheds light on bacterial virulence mechanisms affecting immune cells.

Area of Science:

  • Microbiology
  • Immunology
  • Molecular Biology

Background:

  • Porphyromonas gingivalis is a bacterium known to produce virulence factors that influence host immune responses.
  • Understanding how these virulence factors impact immune cells, such as T cells, is crucial for comprehending host-pathogen interactions.

Purpose of the Study:

  • To investigate the role of specific P. gingivalis virulence factors in inducing apoptosis in Jurkat T cells.
  • To elucidate the molecular mechanisms underlying T-cell apoptosis triggered by P. gingivalis.

Main Methods:

  • Incubation of Jurkat T cells with P. gingivalis culture supernatants.
  • Assessment of apoptosis induction.
  • Analysis of histone H4 acetylation levels.
  • Experiments using protease inhibitors and P. gingivalis protease-deficient mutants.

Main Results:

  • P. gingivalis culture supernatants induced apoptosis in Jurkat T cells, similar to butyric acid.
  • This apoptosis induction was correlated with increased histone H4 acetylation.
  • Proteases from P. gingivalis were found not to be responsible for stimulating T-cell apoptosis.

Conclusions:

  • P. gingivalis virulence factors, independent of proteases, can induce T-cell apoptosis.
  • Histone H4 acetylation is implicated in the apoptotic process mediated by P. gingivalis supernatants.
  • These findings contribute to understanding how oral bacteria modulate host immune cell function.

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