Design and characterization of microspheres for a 3D mesenchymal stem cell culture.

• A simple and low-cost method for PFVH/CH microspheres production is presented. • The study with RAW 264.7 showed absence of a cytotoxic response for these materials. • Convincing 3D cell culture was achieved by using Chitosan-based microspheres. • Microspheres are biomimetic 3D environments that can be freely remodeled by MSCs. • Microspheres could be a versatile system for a wide variety of applications. Recent studies have shown the relevance of growing mesenchymal stem cells (MSCs) in three-dimensional environments with respect to the monolayer cell culture on an adherent substrate. In this sense, macroporous scaffolds and hydrogels have been used as three-dimensional (3D) supports. In this work, we explored the culture of MSCs in a 3D environment created by microspheres, prepared with a fumarate-vinyl acetate copolymer and chitosan. In this system, the environment that the cells feel has similarities to that found by the cells encapsulated in a hydrogel, but the cells have the ability to reorganize their environment since the microspheres are mobile. We evaluated their biocompatibility in vitro using RAW 264.7 macrophages and bone marrow mesenchymal stem cells (BMSCs). The results with RAW 264.7 cells showed good cell viability, without evident signs of cytotoxicity. BMSCs not only proliferate, but also rearrange to grow in clusters, thus highlighting the advantages of microspheres as 3D environments. [ABSTRACT FROM AUTHOR]