title: Dual regulation of osteoclast differentiation by periodontal ligament cells through RANKL stimulation and OPG inhibition.
abstract: Periodontal ligament (PDL) cells play an important role in maintaining the homeostasis of periodontal tissues. However, it is not known how PDL cells contribute to osteoclastogenesis. In this study, we examined the consequences of cell-to-cell interactions between peripheral blood mononuclear cells (PBMCs) and PDL cells during osteoclastogenesis. PBMCs were co-cultured directly or indirectly with PDL cells for two to four weeks. PBMCs that were directly co-cultured with PDL cells formed significantly more resorption pits on dentin slices than did PBMCs that were cultured alone. However, soluble factor(s) produced from PDL cells inhibited the formation of tartrate-resistant acid phosphatase (TRAP)-positive multinucleated cells. Furthermore, PDL cells expressed both receptor activator nuclear factor kappa B ligand (RANKL) and osteoprotegerin (OPG) mRNA. In conclusion, PDL cells support osteoclastogenesis through cell-to-cell contact. PDL cells might regulate osteoclastogenesis by opposing mechanisms--stimulation of resorptive activity by RANKL and inhibition by OPG--thus affecting processes such as periodontitis and orthodontic tooth movement.
authors.affiliation: Department of Life Long Oral Health Science, Graduate School of Dentistry, Tohoku University, Sendai, Japan. kanzaki@orthod.dent.tohoku.ac.jp
authors.forename: H
authors.initials: H
authors.lastname: Kanzaki
authors.forename: M
authors.initials: M
authors.lastname: Chiba
authors.forename: Y
authors.initials: Y
authors.lastname: Shimizu
authors.forename: H
authors.initials: H
authors.lastname: Mitani
mesh_terms: D000135:Acid Phosphatase / Q000037:antagonists & inhibitors; D000328:Adult; D000818:Animals; D002352:Carrier Proteins / Q000235:genetics / Q000378:metabolism*; D002417:Cattle; D002450:Cell Communication; D002454:Cell Differentiation; D002478:Cells, Cultured; D018920:Coculture Techniques; D003804:Dentin / Q000378:metabolism / Q000473:pathology; D004791:Enzyme Inhibitors / Q000378:metabolism; D006023:Glycoproteins / Q000037:antagonists & inhibitors* / Q000235:genetics; D006801:Humans; D007527:Isoenzymes / Q000037:antagonists & inhibitors; D007963:Leukocytes, Mononuclear / Q000166:cytology; D008024:Ligands; D008297:Male; D008562:Membrane Glycoproteins / Q000235:genetics / Q000378:metabolism*; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D010010:Osteoclasts / Q000502:physiology*; D053244:Osteoprotegerin; D010513:Periodontal Ligament / Q000166:cytology*; D053245:RANK Ligand; D012333:RNA, Messenger / Q000032:analysis; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors* / Q000235:genetics; D018124:Receptors, Tumor Necrosis Factor / Q000037:antagonists & inhibitors* / Q000235:genetics / Q000378:metabolism*; D012391:Root Resorption / Q000378:metabolism / Q000473:pathology; D000071681:Tartrate-Resistant Acid Phosphatase; D014409:Tumor Necrosis Factor-alpha / Q000235:genetics / Q000378:metabolism*
chemical_list: D002352:Carrier Proteins; D004791:Enzyme Inhibitors; D006023:Glycoproteins; D007527:Isoenzymes; D008024:Ligands; D008562:Membrane Glycoproteins; D016328:NF-kappa B; D053244:Osteoprotegerin; D053245:RANK Ligand; D012333:RNA, Messenger; D053246:Receptor Activator of Nuclear Factor-kappa B; D018160:Receptors, Cytoplasmic and Nuclear; D018124:Receptors, Tumor Necrosis Factor; C505686:TNFRSF11A protein, human; C506030:TNFRSF11B protein, human; C505688:TNFSF11 protein, human; D014409:Tumor Necrosis Factor-alpha; D000135:Acid Phosphatase; D000071681:Tartrate-Resistant Acid Phosphatase