MG-63 Osteoblast culture on P culture on PLA– based copolymers for bone tissue engineering applications

Physical injury or pathological changes such as removal of a tumor can result in large bone defects, preventing the recovery of its original function. Autogenous bone grafting, which is the most common technique for bone defect repairing, is associated with serious limitations, e.g. limited supply and donor site morbidity. Since a few years bone tissue engineering by degradable biomaterials has been shown as a very promising avenue for providing bone substitutes. Among these materials, bioresorbable synthetic polymers such as poly(ethylene oxide) (PEO), poly(vinyl alcohol) (PVA), poly(acrylic acid) (PAA) and poly(lactic acid) (PLA) are very appealing because their chemistry and properties are controllable and reproducible. Cellular activity and proliferation of osteosarcoma cell lines (MG-63) on films were determined by the tetrazolium salt MTT assay and by phase contrast/fluorescence microscope observations. The cytotoxicity of the materials was found to be low or negligible. Cells viability variations were observed on the surface of the films. Long-term cell culture and degradability of PLA-PEOpolymer film was investigated by optical microscopy (Giemsa staining) and environmental scanning electron microscopy (ESEM). Hydrolysis of the PLLA ester linkages led to slow film degradation. After 113 days, optical microscope observations revealed the presence of large cracks on the surface, and even breaks of small polymer fragments, while MG-63 proliferation was still very important, showing a tissue-like aspect, with extracellular matrix (ECM) deposition. These results show that PLA-PEO copolymers are very interesting bioresorbable materials for long-term bone tissue engineering applications.Optimisation d’un biomatériau composite fibre-hydrogel-cellule destiné à promouvoir la reconstruction osseus