Scalable expansion of human-induced pluripotent stem cells in xeno-free microcarriers.

The expansion of human-induced pluripotent stem cells (hiPSCs) is commonly performed using feeder layers of mouse embryonic fibroblasts or in feeder-free conditions in two-dimensional culture platforms, which are associated with low production yields and lack of process control. Robust large-scale production of these cells under defined conditions has been one of the major challenges to fulfil the large cell number requirement for drug screening applications, toxicology assays, disease modeling and potential cellular therapies. Microcarrier-based systems, in particular, are a promising culture format since they provide a high surface-to-volume ratio and allow the scale-up of the process to stirred suspension bioreactors. In this context, this chapter describes a detailed methodology for the scalable expansion of hiPSCs in spinner flasks and using xeno-free microcarriers to allow further translation to Good Manufacturing Practice (GMP) conditions.