Advanced physiological maturation of human iPSC-derived cardiomyocytes using an algorithm-directed optimization of defined media components

Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) hold tremendous promise for in vitro modeling to assess native myocardial function and disease mechanisms, as well as testing drug safety and efficacy. However, current hiPSC-CMs are functionally immature, resembling in vivo CMs of fetal or neonatal developmental states. The use of targeted culture media and organoid formats have been identified as potential high-yield contributors to improve CM maturation. This study presents an hiPSC-CM maturation medium formulation, designed using a differential evolutionary approach targeting metabolic functionality for iterative optimization. Relative to existing high-performing reference formulations, our medium significantly matured morphology, Ca2+ handling, electrophysiology, and metabolism, which was further validated by multi-omic screening, for cells in either pure or co-cultured microtissue formats. Together, these findings not only provide a reliable workflow for highly functional hiPSC-CMs for downstream use, but also demonstrate the power of high-dimensional optimization processes in evoking advanced biological function in vitro. Using an evolutionary optimization approach, the authors report a culture medium that matures stem cell-derived heart cells, improving their structure, metabolism and electrical activity to advance highly functional models for in vitro testing.