High-density hiPSCs expansion supported by growth factors accumulation in a simple dialysis-culture platform

Abstract

Three-dimensional aggregate-suspension culture can produce large numbers of human induced pluripotent stem cells (hiPSCs); however, use of expensive growth factors and method-induced mechanical stress potentially result in inefficient production costs and difficulties in preserving pluripotency. Here, we developed a simple, miniaturized, dual-compartment dialysis-culture device based on a conventional membrane-culture insert with deep well plates. The device allowed growth-factor accumulation and improved cell expansion up to ~ 32 × 106 cells/mL, and reduction of excessive shear stress and agglomeration following addition of the functional polymer FP003 supported high-density expansion. The results revealed accumulation of several growth factors, including fibroblast growth factor 2 and insulin, along with endogenous NODAL, which acts as a substitute for depleted transforming growth factor-β1 in maintaining pluripotency. Because we used the same growth-factor formulation per volume in the upper culture compartment, cost reduction increased significantly in proportional manner with cell density. We showed that growth-factor-accumulation dynamics in a low-shear-stress environment successfully improved hiPSC proliferation, pluripotency, and differentiation potential. This miniaturised dialysis-culture system demonstrated the feasibility and cost-effective mass production of hiPSCs in high-density culture.