Blocking proinflammatory cytokine release modulates peripheral blood mononuclear cell response to Porphyromonas gingivalis

J Periodontol. 2013 Sep;84(9):1337-45. doi: 10.1902/jop.2012.120422. Epub 2012 Nov 23.

Abstract

Background: Chronic periodontitis (CP) is an inflammatory disease in which cytokines play a major role in the progression of disease. Anti-inflammatory cytokines (interleukin 4 [IL-4] and IL-10) were reported to be absent or reduced in diseased periodontal tissues, suggesting an imbalance between the proinflammatory and anti-inflammatory mediators. This study tests the hypothesis that there is cellular crosstalk mediated by proinflammatory and anti-inflammatory cytokines and that blocking proinflammatory cytokine (tumor necrosis factor-α [TNF-α] and IL-1) production will enhance anti-inflammatory cytokine (IL-4 and IL-10) production from peripheral blood mononuclear cells (PBMCs) in response to Porphyromonas gingivalis.

Methods: PBMCs were isolated from individuals diagnosed with CP or healthy individuals and cultured for 24 hours. Concanavalin A (ConA) was used as an activator of lymphocyte function. Live and heat-killed P. gingivalis or lipopolysaccharide from P. gingivalis were used as the bacterial stimulants. TNF-α and IL-1 production was neutralized by specific antibodies against TNF-α and IL-1α or IL-β. Culture supernatants were evaluated by enzyme-linked immunosorbent assay for TNF-α, IL-1β, IL-4, and IL-10 production.

Results: Live P. gingivalis did not result in any significant IL-10 or IL-4 release, whereas heat-killed P. gingivalis led to a significant increase in IL-10 levels compared with unstimulated or live P. gingivalis-stimulated cells from both healthy individuals or those with CP. Overall, PBMCs from patients with CP produced significantly lower IL-10 in response to ConA and P. gingivalis, suggesting chronic suppression of the anti-inflammatory cytokine production. Blocking the proinflammatory cytokine response did not result in any substantial change in IL-10 or IL-4 response to live P. gingivalis. Blocking the proinflammatory cytokine response restored IL-10 production by cells from CP in response to P. gingivalis lipopolysaccharide.

Conclusions: These findings suggest that PBMCs from patients with CP have suppressed anti-inflammatory cytokine production that can, in part, be restored by neutralizing proinflammatory cytokines. Monocytes are an important source of IL-10 production, and monocyte-derived IL-10 might play a regulatory role in the pathogenesis of CP.

Publication types

  • Comparative Study
  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Case-Control Studies
  • Cell Culture Techniques
  • Cells, Cultured
  • Chronic Periodontitis / immunology
  • Chronic Periodontitis / microbiology
  • Concanavalin A / pharmacology
  • Cytokines / antagonists & inhibitors*
  • Cytokines / immunology
  • Female
  • Humans
  • Inflammation Mediators / antagonists & inhibitors*
  • Inflammation Mediators / immunology
  • Interleukin-10 / analysis
  • Interleukin-10 / immunology
  • Interleukin-1alpha / antagonists & inhibitors
  • Interleukin-1beta / antagonists & inhibitors
  • Interleukin-4 / analysis
  • Interleukin-4 / immunology
  • Leukocytes, Mononuclear / drug effects
  • Leukocytes, Mononuclear / immunology
  • Leukocytes, Mononuclear / microbiology*
  • Lipopolysaccharides / pharmacology
  • Lymphocyte Activation / drug effects
  • Male
  • Monocytes / drug effects
  • Monocytes / immunology
  • Monocytes / microbiology
  • Phagocytes / drug effects
  • Phagocytes / immunology
  • Phagocytes / microbiology
  • Porphyromonas gingivalis / immunology*
  • Tumor Necrosis Factor-alpha / antagonists & inhibitors

Substances

  • Cytokines
  • IL10 protein, human
  • IL4 protein, human
  • Inflammation Mediators
  • Interleukin-1alpha
  • Interleukin-1beta
  • Lipopolysaccharides
  • Tumor Necrosis Factor-alpha
  • Concanavalin A
  • Interleukin-10
  • Interleukin-4