Adhesion, proliferation, and osteogenic differentiation of a mouse mesenchymal stem cell line (BMC9) seeded on novel melt-based chitosan/polyester 3D porous scaffolds

The aim of the present work was to study the biological behavior of a mouse mesenchymal stem cell line when seeded and cultured under osteogenic conditions onto novel processed melt-based chitosan scaffolds. Scaffolds were produced by compression molding, followed by salt leaching. Scanning electron microscopy (SEM) observations and μCT analysis showed the pore sizes ranging between 250 and 500 μm and the interconnectivity of the porous structure. The chitosan-poly(butylenes succinate) scaffolds presented high mechanical properties, similar to the ones of trabecular bone (E1% ∼ 75 MPa). Cytotoxicity assays were carried out using standard tests (accordingly to ISO/EN 10993 part 5 guidelines), namely, MTS test with a 24 h extraction period, revealing that L929 cells had similar metabolic activities to that obtained for the negative control. Cell culture studies were conducted using a mouse mesenchymal stem cell line (BMC9). Cells were seeded onto the scaffold and allowed to proliferate for 3 weeks under osteogenic conditions. SEM observations demonstrated that cells were able to proliferate and massively colonize the scaffolds structure. The cell viability assay MTS demonstrated that BMC9 cells were viable after 3 weeks of culture. The cells clearly evidenced a positive differentiation toward the osteogenic lineage, as confirmed by the high ALP activity levels. Moreover, energy dispersive spectroscopy (EDS) analysis revealed the presence of Ca and P in the elaborated extracellular matrix (ECM). These combined results indicate that the novel melt-based chitosan/polyester scaffolds support the adhesion, proliferation, and osteogenic differentiation of the mouse MSCs and shows adequate physicochemical and biological properties for being used as scaffolds in bone tissue engineering-related strategies.