Development of a 3D human osteoblast cell culture model for studying mechanobiology in orthodontics

Damien Brezulier (1, 2) , Pascal Pellen-Mussi (2) , Sylvie Tricot-Doleux (2) , Agnès Novella (2) , Olivier Sorel (1) , Sylvie Jeanne (1, 2)

1 Centre Hospitalier Universitaire de Rennes [CHU Rennes] = Rennes University Hospital [Ponchaillou]
2 ISCR - Institut des Sciences Chimiques de Rennes

Objectives: Mechanobiology phenomena constitute a major element of the cellular and tissue response during orthodontic treatment and the implantation of a biomaterial. Better understanding these phenomena will improve the effectiveness of our treatments. The objective of this work is to validate a model of three-dimensional (3D) culture of osteoblasts to study mechanobiology.Materials and methods: The hFOB 1.19 cell line was cultured either traditionally on a flat surface or in aggregates called spheroids. They were embedded in 0.8% low-melting agarose type VII and placed in a polyethylene terephthalate transwell insert. Compressive forces of 1 and 4 g/cm2 were applied with an adjustable weight. Proliferation was evaluated by measuring diameters, monitoring glucose levels, and conducting Hoechst/propidium iodide staining. Enzyme-linked immunosorbent assays focusing on the pro-inflammatory mediators interleukin (IL)-6 and IL-8 and bone remodelling factor osteoprotegerin were performed to evaluate soluble factor synthesis. quantitative reverse transcription-polymerase chain reaction was performed to evaluate bone marker transcription.Results: The 3D model shows good cell viability and permits IL dosing. Additionally, three gene expression profiles are analysable.Limitations: The model allows analysis of conventional markers; larger exploration is needed for better understanding osteoblast mechanobiology. However, it only allows an analysis over 3 days.Conclusion: The results obtained by applying constant compressive forces to 3D osteoblastic cultures validate this model system for exploring biomolecule release and analysing gene transcription. In particular, it highlights a disturbance in the expression of markers of osteogenesis.

Domaines: Chimie

Damien Brezulier, Pascal Pellen-Mussi, Sylvie Tricot-Doleux, Agnès Novella, Olivier Sorel, et al.. Development of a 3D human osteoblast cell culture model for studying mechanobiology in orthodontics. European Journal of Orthodontics, 2020, 42 (4), pp.387-395. ⟨10.1093/ejo/cjaa017⟩. ⟨hal-02533165⟩