Background: There is limited knowledge regarding differentiation of osteoclasts in the presence of nanoscale bioactive glass (nBG). This investigation examined increasing concentrations of 45S5 nBG and their influence on osteoclast differentiation.
Materials & methods: Different concentrations of 45S5 nBG were cultured up to 14 days with the murine RAW264.7 cell line and human primary monocytes cultured with M-CSF and RANKL.
Results: Culturing cells for 14 days with 500 μg/ml nBG showed a viability of 100%; however DNA synthesis was reduced, supporting differentiation into osteoclast-like cells. Using RAW cells, activation of nine genes, including cell fusion genes, occurred in an nBG concentration dependent manner. Low concentrations of nBG increased expression of genes involved in commitment to cell fusion, whereas high concentrations increased gene expression supporting osteoclast-like differentiation.
Conclusion: nBG enhances both RAW264.7 and human osteoclast differentiation. nBG controlled gene expression in a concentration dependent manner could reflect normal regulation during bone growth.
Keywords: bioactive glass; biomaterials; bone tissue engineering; nanoparticles; osteoclasts.