Soft tissue compatibility of Li, Sr and B doped bioactive glasses

Bioactive glasses are in clinical use in many bone-related applications. The main advantage of these materials comes from the ease of introducing any ions having potential therapeutic effects and controlling their release in the medium. However, little is known about their reactions with soft tissue. In this study, human adipose stem cells (hASC), human lung fibroblasts and urethral epithelium cells were cultured for 14 days in mediums based on 13-93 bioactive glass extracts doped with lithium, strontium or boron. The cell viability, proliferation and phenotype were studied and the ion concentrations in the extract-based mediums were quantified using ICP-OES. The initial results show that the hASC and the fibroblasts remain viable in the extracts and the 13-93 and Li-doped glasses perform as well as the basic medium with hASC. According to the live-dead images, the other glasses slow down the cells proliferation, but these results will be confirmed with the quantitative analysis. Culturing the hASC and fibroblasts in the boron-containing extract seems to increase the cell size. The extracts had a very distinct effect on the morphology of the urethral epithelium cells, especially the Li-containing extract resulted in a very different cell morphology compared to the reference medium. This is most likely due to the high calcium concentration in the extract, which is not well tolerated by epithelial cells.