Protocol for expansion of undifferentiated human embryonic and pluripotent stem cells in suspension.

Human embryonic and induced pluripotent stem cells (hESCs and hiPSCs) offer a platform technology with the potential for developmental biology and cell-based therapy. Therefore, robust and cost-effective ways for mass production of them is necessary. Here, we have presented a protocol to grow pluripotent hESCs and hiPSCs in suspension by using a simple, inexpensive, microcarrier-free method. Under this condition, the cells maintained stability during freeze/thaw cycles without the loss of pluripotency markers for extended periods (>1 year). The cells maintained a stable karyotype and showed very similar expression profiles when compared to the adherent culture. The combination of this system with a bioreactor culture system will allow scale up culture of hESCs and hiPSCs needed for clinical and translational applications.