The effect of bioactive glasses on bone marrow stromal cells differentiation.

Bone marrow is a mixture of hematopoietic, vascular, stromal and mesenchymal cells capable of skeletal repair/regeneration thanks to the ability of bone marrow cells to differentiate into osteoblasts and osteoclasts. This ability is important in tissue regeneration during fracture healing, or for successful osteointegration of implanted prostheses, and in bone remodelling. Therefore, bone marrow cell culture systems seem to be useful and relatively close to in vivo conditions models to study interactions occurring at the cell-material interface of implants directed to hard tissue engineering. The purpose of this study was to investigate the ability of three bioactive glasses (45S, 58S and 77S) to induce osteogenic differentiation and cell mineralisation. A significant effect of the 45S and 77S bioactive materials was seen on early differentiation of the marrow stromal cells into osteoblast-like cells. 45S bioglass evidenced also the highest effect on cell mineralisation at the same level as cells treated with dexametasone, used as positive control. 77S treated cells evidenced also a significant inhibition in the number of multinucleated TRAP-positive cells (ostoclast-like cells) in comparison with the control untreated cells and in marrow cells treated with 45S and 58S bioactive glasses. These findings have potential implications and applications for tissue engineering where three-dimensional bioactive glass substrates could be used as scaffolds for in vitro production of bioengineered bone.