Growth Factor-Based Manufacturing of Human Pluripotent Stem Cell-Derived Cardiomyocytes Using the Vertical Wheel Bioreactor System

This publication describes scalable expansion of human pluripotent stem cells and growth factor-directed differentiation into cardiomyocytes in Vertical-Wheel bioreactors. Expansion studies evaluated inoculation density, agitation, media exchange, aggregate size, metabolites, viability, and pluripotency. Cardiac differentiation was then optimized using BMP4, Activin A, and bFGF. Adjustments to aggregation and mesoderm induction enabled production of more than one million cardiac troponin T-positive cells per milliliter. The process was reproduced in 500 mL bioreactors, with an average yield of approximately 1.11 million cardiomyocytes per milliliter and mean cardiac purity of 93%. Variations in growth-factor ratios supported distinct cardiac phenotypes. Bioreactor-produced cardiomyocytes exhibited expected electrophysiological and contractile properties and engrafted in an infarcted guinea pig myocardium model.