Strategies for the Expansion of Human Induced Pluripotent Stem Cells as Aggregates in Single-Use Vertical-Wheel Bioreactors

This publication evaluates the expansion of human induced pluripotent stem cells as free-floating aggregates in a 0.1 L Vertical-Wheel bioreactor operated at a 60 mL working volume. Two commercial media and repeated-batch or fed-batch strategies were assessed, together with dextran sulfate supplementation. Dextran sulfate increased maximum cell numbers in both media conditions, while mTeSR1 with supplementation produced the highest cell density and reduced the required culture duration. The optimized condition achieved approximately 2.3 million cells per milliliter after five days, with an average aggregate diameter of approximately 346 micrometers. Flow cytometry, gene-expression analysis, and differentiation testing confirmed maintenance of pluripotency. The study establishes an aggregate-based, single-use bioreactor workflow for efficient hiPSC expansion and identifies medium formulation and supplementation as important process variables.