A novel cardiac differentiation method of a large number and uniformly-sized spheroids using microfabricated culture vessels.

Cardiomyocytes differentiated from human induced pluripotent stem cells (hiPSCs) have great potential for regenerative medicine and drug discovery. In this study, we developed a novel protocol to more reproducibly and efficiently induce cardiomyocytes. A large quantity of uniformly sized spheroids were generated from hiPSCs using microfabricated vessels and induced into cardiac differentiation. In the middle of the cardiac differentiation process, spheroids were then dissociated into single cells and reaggregated into smaller spheroids using the microfabricated vessels. This reaggregation process raised and expression levels and improved the quality of cardiomyocyte population compared to that in a control group in which dissociation and reaggregation were not performed.