IADR Abstract Archives

Macrophage-Fibroblast Interactions Modulate Dental Pulp Regeneration

Objectives: Pulp regeneration is a complex process which requires intercellular communications among pulp cells. Indeed, depending on their stimulation recent data have demonstrated that fibroblasts regulate macrophage M1/M2 phenotype differentiation. Here we aimed at investigating the effects of macrophage-pulp fibroblast interaction on pulp stem cell (DPSCs) proliferation and recruitment as well as on angiogenesis.
Methods: Human pulp cells were isolated from third molars. DPSCs were separated from fibroblasts using magnetic cell sorting with STRO-1. Two types of stimulation were performed to simulate pulp injury: 1) to mimic a carious lesion, fibroblasts were incubated with Lipoteichoic Acid (LTA) and physically injured; 2) to simulate an inflammatory reaction, fibroblasts were physically injured without LTA. Fibroblast supernatants were then incubated with undifferentiated macrophages (M0) to induce their differentiation into M1/M2. VEGF secretion by macrophages was quantified by ELISA. The macrophage supernatants’ effects on endothelial cell (HUVEC) proliferation was investigated with the MTT assay while neo-angiogenesis was studied after endothelial cell culture on Matrigel. DPSCs proliferation and recruitment towards macrophage supernatants were investigated with MTT and Boyden chambers respectively.
Results: M2 and macrophages incubated with injured fibroblast supernatants induced a significant increase of VEGF secretion and neo-angiogenesis as well as DPSCs proliferation as compared to M0, M1 and those incubated with LTA. An important level of DPSCs recruitment was observed with M0, M1 and macrophages incubated with LTA-stimulated fibroblast supernatants. This was significantly higher than that observed with M2 and injured fibroblast supernatants.
Conclusions: Within the limits of this investigation in vitro, when macrophages are incubated with fibroblast supernatants, they differentiate into M1 or M2 depending on the fibroblast stimulation type and modulate neo-angiogenesis and DPSC recruitment. These are two major steps in the pulp regeneration process. This fine balance between M1 and M2 phenotypes represents a pre-requisite for a successful regeneration process.

2021 Continental European and Scandinavian Divisions Meeting (Brussels, Belgium, Hybrid)
Brussels, Belgium, Hybrid
2021
0013
Pulp Biology & Regeneration Research
  • Jeanneau, Charlotte  ( Aix Marseille Université, Centre National de la Recherche Scientifique, Institut des Sciences du Mouvement , Marseille , France )
  • Le Fournis, Chloé  ( Aix Marseille Université, Centre National de la Recherche Scientifique, Institut des Sciences du Mouvement , Marseille , France )
  • Roumani, Sandra  ( Aix Marseille Université, Centre National de la Recherche Scientifique, Institut des Sciences du Mouvement , Marseille , France )
  • Cotten, Aurélie  ( Aix Marseille Université, Centre National de la Recherche Scientifique, Institut des Sciences du Mouvement , Marseille , France )
  • Giraud, Thomas  ( Aix Marseille Université, Centre National de la Recherche Scientifique, Institut des Sciences du Mouvement , Marseille , France ;  Assistance Publique – Hôpitaux de Marseille, Hôpital Timone, Service d’Odontologie , Marseille , France )
  • About, Imad  ( Aix Marseille Université, Centre National de la Recherche Scientifique, Institut des Sciences du Mouvement , Marseille , France )
  • NONE
    Oral Session IN PERSON
    Pulp biology & regeneration
    Thursday, 09/16/2021 , 01:30PM - 02:45PM