title: A challenge with Porphyromonas gingivalis differentially affects the osteoclastogenesis potential of periodontal ligament fibroblasts from periodontitis patients and non-periodontitis donors.
abstract: OBJECTIVE
  Porphyromonas gingivalis (Pg) may cause an immune-inflammatory response in host cells leading to bone degradation by osteoclasts. We investigated the osteoclast-inducing capacity of periodontal ligament fibroblasts from periodontitis patients and non-periodontitis donors after a challenge with viable Pg.
  
  
  METHODS
  PDLFs from periodontitis patients (n = 8) and non-periodontitis donors (n = 7) were incubated for 6 h with or without viable Pg and subsequently co-cultured with osteoclast precursors from peripheral blood mononuclear cells (PBMCs). The number of multinucleated tartrate-resistant acid phosphatase-positive cells was determined at 21 days. Expression of osteoclastogenesis-associated genes was assessed after infection of PDLFs mono-cultures and in PDLFs-PBMCs co-cultures. Resorption activity was analysed on bone slices.
  
  
  RESULTS
  Pg induced the expression of osteoclastogenesis-associated genes by PDLFs. After bacterial challenge the formation of osteoclast-like cell was decreased in co-cultures of PBMCs with non-periodontitis PDLFs, but not with PDLFs from periodontitis patients.
  
  
  CONCLUSIONS
  PDLFs from sites free of periodontitis respond to an infection with Pg by tempering formation of osteoclast-like cells, probably promoting clearance of the infection. PDLFs from periodontitis sites are desensitized to a Pg challenge in terms of their osteoclast-inducing capacity.
authors.affiliation: Department of Periodontology, Academic Centre for Dentistry Amsterdam (ACTA), Research Institute MOVE, University of Amsterdam and VU University Amsterdam, Amsterdam, The Netherlands.
authors.forename: Dimitris
authors.initials: D
authors.lastname: Sokos
authors.forename: Nina
authors.initials: N
authors.lastname: Scheres
authors.forename: Ton
authors.initials: T
authors.lastname: Schoenmaker
authors.forename: Vincent
authors.initials: V
authors.lastname: Everts
authors.forename: Teun J
authors.initials: TJ
authors.lastname: de Vries
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis; D000199:Actins / Q000032:analysis; D001862:Bone Resorption / Q000473:pathology; D024402:Carbonic Anhydrase II / Q000032:analysis; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000502:physiology; D018920:Coculture Techniques; D005260:Female; D005347:Fibroblasts / Q000382:microbiology / Q000502:physiology*; D015726:Giant Cells / Q000473:pathology; D006801:Humans; D007527:Isoenzymes / Q000032:analysis; D007963:Leukocytes, Mononuclear / Q000502:physiology; D008297:Male; D008875:Middle Aged; D010010:Osteoclasts / Q000502:physiology*; D053244:Osteoprotegerin / Q000032:analysis; D010513:Periodontal Ligament / Q000166:cytology* / Q000382:microbiology; D010518:Periodontitis / Q000473:pathology*; D016966:Porphyromonas gingivalis / Q000502:physiology*; D053245:RANK Ligand / Q000032:analysis; D000071681:Tartrate-Resistant Acid Phosphatase; D013997:Time Factors
chemical_list: D000199:Actins; D007527:Isoenzymes; D053244:Osteoprotegerin; D053245:RANK Ligand; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase; D024402:Carbonic Anhydrase II
keywords: Porphyromonas gingivalis; TRACP; co-culture; osteoclast; osteoclast formation; periodontal ligament fibroblasts; periodontitis