On the in Vitro Biocompatibility Testing of Bioactive Glasses

In this work, a new 3D cellular model—based on human bone marrow mesenchymal stem cells (BM–MSCs)—was used for the first time to test the 45S5 Bioglass(®) (45S5). Such a model, previously used to evaluate the biologic performance of two novel bioactive glasses, suggested out the regenerative potential of such materials. In fact, BM–MSCs were able both to adhere and colonize the biomaterials, as well as differentiate toward osteoblasts—even in absence of specific growth factors. Surprisingly, BM–MSCs were not able to colonize 45S5 granules (almost no adhesion and/or colonization was observed), and thus, were not capable of providing any osteogenic differentiation. Therefore, the model seems to suggest that the two novel bioactive glasses have a better biologic performance than 45S5. If this hypothesis is confirmed also by in vivo tests, the 3D model may become a predictive tool for discriminating between different potential bioactive materials by comparatively evaluating them, and preliminarily selecting the best ones in relation to their biocompatibility potential—before proceeding with further experiments in vivo. This approach could favor the reduction of costs and time of pre-clinical and clinical trials.