Growth, differentiation capacity, and function of mesenchymal stem cells expanded in serum-free medium developed via combinatorial screening

• A combinatorial screening strategy was successfully used to develop a serum free MSC medium.
• The serum free medium allows high yield growth of MSCs which maintain immunophenotype and differentiation potential.
• MSCs grown in serum free conditions suppress T cell activation.
• Gene expression profiles of serum free grown MSCs are consistent with equal or improved function.

The presence of serum in cell culture medium presents an obstacle to safe and efficient production of hMSCs for therapeutic purposes. Availability of defined medium will be crucial to elucidating the mechanism of action of hMSCs in many indications as well as a prerequisite to consistently produce cells with predictable performance characteristics.Using a bioinformatics driven approach, which we call the BD Discovery Platform, we have developed a novel serum-free medium that supports highly efficient growth while maintaining the surface markers and functional characteristics defining hMSCs. In a comparison with serum-containing and other commercially available serum-free formulations, all conditions led to expansion of cells that meet the minimal criteria for hMSCs as set by the International Society for Cellular Therapy (ISCT). However, differences in growth characteristics and gene expression patterns suggest that expansion in serum-free growth conditions can provide greater yields in a shorter time. The mRNA expression profile observed in cells grown without serum suggests upregulation of several genes implicated in hMSC function as well as downregulation of the proinflammatory cytokine IL6.