title: Saliva suppresses osteoclastogenesis in murine bone marrow cultures.
abstract: Saliva can reach mineralized surfaces in the oral cavity; however, the relationship between saliva and bone resorption is unclear. Herein, we examined whether saliva affects the process of osteoclastogenesis in vitro. We used murine bone marrow cultures to study osteoclast formation. The addition of fresh sterile saliva eliminated the formation of multinucleated cells that stained positive for tartrate-resistant acid phosphatase (TRAP). In line with the histochemical staining, saliva substantially reduced gene expression of cathepsin K, calcitonin receptor, and TRAP. Addition of saliva led to considerably decreased gene expression of receptor activator of nuclear factor kappa-B (RANK) and, to a lesser extent, that of c-fms. The respective master regulators of osteoclastogenesis (c-fos and NFATc1) and the downstream cell fusion genes (DC-STAMP and Atp6v0d2) showed decreased expression after the addition of saliva. Among the costimulatory molecules for osteoclastogenesis, only OSCAR showed decreased expression. In contrast, CD40, CD80, and CD86-all costimulatory molecules of phagocytic cells-were increasingly expressed with saliva. The phagocytic capacity of the cells was confirmed by latex bead ingestion. Based on these in vitro results, it can be concluded that saliva suppresses osteoclastogenesis and leads to the development of a phagocytic cell phenotype.
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Switzerland Laboratory of Oral Cell Biology, School of Dental Medicine, University of Bern, Switzerland Department of Oral and Maxillofacial Surgery, School of Dental Medicine, Universitat Internacional de Catalunya, Barcelona, Spain.
authors.forename: J
authors.initials: J
authors.lastname: Caballé-Serrano
authors.affiliation: Laboratory of Oral Cell Biology, School of Dental Medicine, University of Bern, Switzerland Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern, Switzerland Department of Conservative Dentistry and Periodontology, Medical University of Vienna, Austria.
authors.forename: B
authors.initials: B
authors.lastname: Cvikl
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Switzerland Robert K. Schenk Laboratory of Oral Histology, School of Dental Medicine, University of Bern, Switzerland.
authors.forename: D D
authors.initials: DD
authors.lastname: Bosshardt
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Switzerland.
authors.forename: D
authors.initials: D
authors.lastname: Buser
authors.affiliation: Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Lussi
authors.affiliation: Department of Oral Surgery and Stomatology, School of Dental Medicine, University of Bern, Switzerland Laboratory of Oral Cell Biology, School of Dental Medicine, University of Bern, Switzerland Department of Preventive, Restorative and Pediatric Dentistry, School of Dental Medicine, University of Bern, Switzerland reinhard.gruber@zmk.unibe.ch.
authors.forename: R
authors.initials: R
authors.lastname: Gruber
mesh_terms: D000135:Acid Phosphatase / Q000032:analysis; D000818:Animals; D018122:B7-1 Antigen / Q000032:analysis; D051940:B7-2 Antigen / Q000032:analysis; D015415:Biomarkers / Q000032:analysis; D001854:Bone Marrow Cells / Q000502:physiology*; D019013:CD40 Antigens / Q000032:analysis; D056657:Cathepsin K / Q000032:analysis; D018929:Cell Culture Techniques; D002454:Cell Differentiation / Q000502:physiology; D002459:Cell Fusion; D002470:Cell Survival / Q000502:physiology; D007527:Isoenzymes / Q000032:analysis; D008565:Membrane Proteins / Q000032:analysis; D051379:Mice; D050778:NFATC Transcription Factors / Q000032:analysis; D009419:Nerve Tissue Proteins / Q000032:analysis; D010010:Osteoclasts / Q000502:physiology*; D010586:Phagocytes / Q000502:physiology; D010587:Phagocytosis / Q000502:physiology; D016760:Proto-Oncogene Proteins c-fos / Q000032:analysis; D053246:Receptor Activator of Nuclear Factor-kappa B / Q000032:analysis; D016186:Receptor, Macrophage Colony-Stimulating Factor / Q000032:analysis; D018003:Receptors, Calcitonin / Q000032:analysis; D011956:Receptors, Cell Surface / Q000032:analysis; D012463:Saliva / Q000502:physiology*; D000071681:Tartrate-Resistant Acid Phosphatase; D025262:Vacuolar Proton-Translocating ATPases / Q000032:analysis
chemical_list: D018122:B7-1 Antigen; D051940:B7-2 Antigen; D015415:Biomarkers; D019013:CD40 Antigens; C497965:Cd86 protein, mouse; C499636:DC-STAMP protein, mouse; D007527:Isoenzymes; D008565:Membrane Proteins; D050778:NFATC Transcription Factors; D009419:Nerve Tissue Proteins; C494005:Nfatc1 protein, mouse; C450519:Oscar protein, mouse; D016760:Proto-Oncogene Proteins c-fos; D053246:Receptor Activator of Nuclear Factor-kappa B; D018003:Receptors, Calcitonin; D011956:Receptors, Cell Surface; C505687:Tnfrsf11a protein, mouse; D016186:Receptor, Macrophage Colony-Stimulating Factor; D000135:Acid Phosphatase; C000605511:Acp5 protein, mouse; D000071681:Tartrate-Resistant Acid Phosphatase; D056657:Cathepsin K; C534132:Ctsk protein, mouse; C542312:Atp6v0d2 protein, mouse; D025262:Vacuolar Proton-Translocating ATPases
keywords: bone regeneration; dendritic cells; dentistry; immunology; macrophages; osteoclast