Application of the water-insoluble, temperature-responsive block polymer poly(butyl methacrylate-block-N-isopropylacrylamide) for pluripotent stem cell culture and cell-selective detachment

Induced pluripotent stem (iPS) cells have been widely studied in regenerative medicine, pathology modeling, and drug screening. Stable mass culture of iPS cells is essential for these applications. iPS cells can spontaneously differentiate into other cells during culture, and removal of these differentiated cells is necessary. Herein, a cost-effective culture method suitable for mass culture and a detailed analysis of the selective detachment of iPS cells are presented. A simple method for coating the water-insoluble thermoresponsive polymer poly (butyl methacrylate-block-N-isopropylacrylamide) on commercially available polystyrene dishes was employed. Analysis of the effects of the polymer composition, coating thickness, and surface structure on iPS cell culture/detachment showed that a coating thickness of approximately 10-40 nm using a polymer with a high poly (N-isopropylacrylamide) content was suitable for iPS cell detachment. Moreover, an interesting change in surface morphology was observed following temperature variation, thereby affecting laminin adsorption. Second, selective detachment in cocultures of iPS cells and differentiated cells enabled collection of iPS cells with more than 98% purity. Finally, long-term iPS cell culture was conducted using temperature-responsive cell detachment. Overall, long-term maintenance-free culture of iPS cells was possible without manual removal of differentiated cells.