Fig. 3

Importance of MSCs in generating 3D cardiac microtissue. (a) Representative image of CMs and MSCs differentiated from the same hESC line when co-cultured as 3D spheroids for day 1 and 7. Cardiac spheroid formation was dependent on the ratio of MSCs to CMs. Scale bars, 100 μm. (b) Average diameters of cardiac spheroids. Data are the means±SD of replicates (n ≥ 5). **p < 0.01. (c) Representative raw traces of the microelectrode array (MEA) recording from control CMs and CMs co-cultured with 5, 10 and 20% MSCs on day 6 after seeding. (d) The representative traces of averaged field potential (FP) recorded by MEA in the control CMs (n = 14) and CMs co-cultured with 5% (n = 37), 10% (n = 49) and 20% MSCs (n = 48). Open triangle indicates the peak of FP and bilateral arrow indicates the field potential duration (FPD). (e) FPD obtained from the control CMs (n = 14) and CMs co-cultured with 5% (n = 37), 10% (n = 49) and 20% MSCs (n = 48). **p < 0.01, *p < 0.05