Differentiation of mouse embryonic stem cells into cardiomyogenic cells incubated with cardiomyocytes

Objective To explore the effect of embryonic stem cells(ESCs) differentiating into cardiomyocytes(CM) by cardiomyocytes.Methods The blastocytes of 3.5 d from Kunming mouse,cultured on mouse embryonic fibroblaste cell feeder layers for 4～5 d,the mouse ESCs were isolated and subsequently cultured.Day 2～3 embryoid bodies(EBs) were derived from ESCs of passage 3 to 5 and then incubated with neonatal cardiomyocyte(CM) to induce into cardiomyocytes and the expression of cardiac specific cardiac troponin-T(TnT) and β-actin were detected by immunofluoresence.Results The rhythmic beating embryoid bodies were observed on day 3 and reached 93% of rhythmic beating embryoid bodies on 12 day in group 2.All the beating cardiomyocytes derived from ESCs expressed cardiac-specific proteins for TnT and β-actin,and the group induced by direct cell contact acquired the highest differentiating ratio as 56.5%,and was the highest differentiating ratio compared with other groups(P0.05).Conclusion Both cardiomyocyte coculturing system and cardiomyocyte-lysate system can induce mouse ESCs to differentiate into cardiomyocyte-like cells and the induced effect of direct cell-to-cell interaction with neonatal cardiomyocytes was higher than that of cardiomyocyte-lysate.