title: Regulatory role of periodontal ligament fibroblasts for innate immune cell function and differentiation.
abstract: Innate immunity is crucial for an effective host defense against pathogenic microorganisms in periodontal tissues. As periodontal ligament (PDL) cells synthesize immunomodulatory cytokines, the aim of this in vitro study was to investigate whether these cells can interact with innate immune cells. Resting and inflammatory primed (IL-1β, TNF-α, HMGB1) human PDL cells were co-cultured with human monocyte-derived dendritic cells or macrophages. Migration, phenotypic maturation and modulation of phagocytosis of Porphyromonas gingivalis by immune cells were investigated upon co-culture with PDL cells and/or their released soluble factors. PDL cells interacted with immune cells under both non-inflammatory and inflammatory conditions. Immune cell migration was significantly enhanced by co-culture with PDL cells, which also affected their phenotypic maturation both through cell-cell contact and through released soluble mediators. The dendritic cell maturation markers CD83 and CD86 were upregulated as much as both 'alternatively activated' M2 macrophage maturation markers CD23 and CD163. In contrast, the 'classically activated' M1 macrophage maturation marker CD64 was downregulated. Finally, PDL cells significantly enhanced the phagocytosis of Porphyromonas gingivalis by immune cells. Our experiments revealed that PDL cells are not only structural elements of the periodontium, but actively influence immune responses by interaction with innate immune cells.
authors.affiliation: Medical Faculty, University of Bonn, Bonn, Germany. konermann@uni-bonn.de
authors.forename: Anna
authors.initials: A
authors.lastname: Konermann
authors.forename: Dirk
authors.initials: D
authors.lastname: Stabenow
authors.forename: Percy A
authors.initials: PA
authors.lastname: Knolle
authors.forename: Stefanie A E
authors.initials: SA
authors.lastname: Held
authors.forename: James
authors.initials: J
authors.lastname: Deschner
authors.forename: Andreas
authors.initials: A
authors.lastname: Jäger
mesh_terms: D002454:Cell Differentiation; D002465:Cell Movement; D049109:Cell Proliferation; D002478:Cells, Cultured; D018920:Coculture Techniques; D003713:Dendritic Cells / Q000276:immunology*; D005347:Fibroblasts / Q000276:immunology*; D024243:HMGB1 Protein / Q000276:immunology; D006801:Humans; D007113:Immunity, Innate; D056747:Immunomodulation; D053583:Interleukin-1beta; D008264:Macrophages / Q000276:immunology*; D010510:Periodontal Diseases / Q000276:immunology*; D010513:Periodontal Ligament / Q000276:immunology*; D010587:Phagocytosis; D016966:Porphyromonas gingivalis / Q000276:immunology*; D014409:Tumor Necrosis Factor-alpha / Q000276:immunology
chemical_list: D024243:HMGB1 Protein; D053583:Interleukin-1beta; D014409:Tumor Necrosis Factor-alpha