oa Attachment of Embryonic Stem Cells-derived Cardiomyocytes in Cultispher-S Microcarriers by using Spinner flask

Embryonic Stem cells have the ability to differentiate under in vitro conditions into cardiomyocytes. A transgenic α-myosin heavy chain (α-MHC+) ES cell line was generated, exhibiting puromycin resistance and expressing enhanced green fluorescent protein (EGFP) under control of the α-MHC+ promoter. A puromycin-resistant, EGFP-positive α-MHC+ cardiomyocyte population was isolated with over 92 percent purity.

The cultivation of these cardiomyocytes, in macroporous gelatine microsphere beads in a spinner flask bioreactor has been studied. The average number of cultivated cells per microsphere was optimised after we specified the most suitable agitation conditions and the optimal time frames of cultivation. Our study shows that 80 percent of microspheres were colonised by cardiomyocytes under optimal conditions. Scanning electron microscopy (SEM) and confocal laser scanning microscopy (CLSM) were used to show that the population of the beads was not limited to the microcarrier surface, but some cells invaded the inner surfaces of the microspheres as well.

The present findings demonstrate the successful culture of α-MHC+ cardiomyocytes in macroporous biodegradable microcarriers while maintaining the typical morphological and electrophysiological properties of cardiomyocytes. Our perspective significantly improves survival of grafted cardiomyocytes and thus helps to overcome current limitations of cell replacement approaches