EVALUATION OF THE CYTOTOXICITY OF PULP FLOOR PERFORATION FILLING MATERIALS BY USING IN PARALLEL 2D AND 3D CULTURE MODELS

Oral Communication presented at the ";Forum des Jeunes Chercheurs";, Brest (France) 2011

Epithelial Cell Surface Sites Involved in the Polyvalent Adherence of Porphyromonas gingivalis: a Convincing Role for Neuraminic Acid and Glucuronic Acid

We investigated the target structures of the epithelial cells responsible for the attachment of Porphyromonas gingivalis by immunocytofluorimetry, enzyme-linked immunosorbent assay, and confocal microscopy. Integrins (β1, β3, and αV) and E-cadherin played no significant role. Carbohydrates (such as α-d-methylglucoside, l-fucose, d- and l-mannose, N-acetylglucosamine, and N-acetylgalactosamine) had little inhibitory effect on bacterial binding. Enzymatic treatments of the epithelial membranes and sugar competition studies showed that N-acetylneuraminic acid and glucuronic acid were involved in binding

Expression of factors involved in dental pulp physiopathological processes by nemotic human pulpal fibroblasts

International audienc

Characterization of a programmed necrosis process in 3-dimensional cultures of dental pulp fibroblasts

International audienceAIM: To analyse and compare the expression of necrosis markers in human lung and dental pulp fibroblasts and to determine whether this process differs by the type of mesenchymal cell. METHODS: Human dental pulp fibroblasts were obtained from unerupted third molars. Sound lung and pulpal fibroblasts were cultured in vitro as spheroids to determine the expression of the necrosis hallmark cyclooxygenase-2 (COX-2) mRNA using RT-PCR and the concentrations of vascular endothelial growth factor (VEGF) and hepatocyte growth factor/scatter factor (HGF/SF) proteins using an ELISA test. Cell viability within spheroids was also compared with spheroid diameters over time. RESULTS: Increased expression of COX-2 and VEGF was found in all spheroids compared with corresponding monolayers. Although HGF/SF was highly expressed in MRC5 cells, dental pulp fibroblasts aggregates maintained only a basal level compared with monolayer cultures. Further, the observed progressive loss of viable cells explained the decreased diameters of spheroids over time. The results demonstrate that necrosis occurs in sound lung and pulpal fibroblasts. This cell death also displays differences between these two different cell types, as they do not produce the same growth factors quantity release. CONCLUSIONS: The necrosis process occurred in human dental pulp fibroblasts and is different between the two cell types studied. This in vitro experimental necrosis model could become an interesting inflammatory tool. More investigations are needed to compare necrosis process in dental pulp fibroblast and inflammation during pulpitis

Evaluation of functional SiO2 nanoparticles toxicity by a 3D culture model

International audienc

3D cell culture to determine in vitro biocompatibility of bioactive glass in association with chitosan

International audienceThis study reports the in vitro biocompatibility of a composite biomaterial composed of 46S6 bioactive glass in association with chitosan (CH) by using 3D osteoblast culture of SaOS2. The 46S6 and CH composite (46S6-CH) forms small hydroxyapatite crystals on its surface after only three days immersion in the simulated body fluid. For 2D osteoblast culture, a significant increase in cell proliferation was observed after three days of contact with 46S6 or 46S6-CH-immersed media. After six days, 46S6-CH led to a significant increase in cell proliferation (128%) compared with pure 46S6 (113%) and pure CH (122%). For 3D osteoblast culture, after six days of culture, there was an increase in gene expression of markers of the early osteoblastic differentiation (RUNX2, ALP, COL1A1). Geometric structures corresponding to small apatite clusters were observed by SEM on the surface of the spheroids cultivated with 46S6 or 46S6-CH-immersed media.We showed different cellular responses depending on the 2D and 3D cell culture model. The induction of osteoblast differentiation in the 3D cell culture explained the differences of cell proliferation in contact with 46S6, CH or 46S6-CH-immersed media. This study confirmed that the 3D cell culture model is a very promising tool for in vitro biological evaluation of bone substitutes' propertie