Cryopreservation of hiPSC Aggregates

A solution of non-DMSO cryoprotective agents (CPAs) was formulated using sucrose, glycerol, L-isoleucine, poloxamer 188 (P188), and human serum albumin as previously optimized for the cryopreservation of hiPSC aggregates (Li et al., 2020 (link)). A commercially available DMSO-based CPA solution (CryoStor 10, BioLife Solutions) was used in comparison. Neuronal cells were incubated in the CPA solution at room temperature. Viable and nonviable cell counts were based on membrane integrity using 10 µM acridine orange (AO) and 15 µM propidium iodide (PI) and measured at 0, 30, and 60 min.