Fig. 1

Phenotypic characteristics of cryopreserved hiPSC-CMs after cardiomyogenic differentiation, purification, and elimination of residual undifferentiated hiPSCs. a: Populations of cryopreserved hiPSC-CMs were assessed via flow cytometry. The histograms show the expression of vimentin, αSMA, and CD31 in the cTnT-negative cell population (representative data of n = 5). The mean cTnT-positive ratio was 70.3% (n = 5). Scale bar: 1 cm. b: Four cell populations in the cryopreserved hiPSC-CMs were determined using single-cell RNA-seq. Violin plots show the expression of the cardiac markers TNNT2 and ACTN2. UMAP plot shows the expression of periostin (a fibroblast marker), SMA (a smooth muscle marker) and CD31 (an endothelial cell marker). c–f: Structure and morphology of cryopreserved hiPSC-CM. Immunofluorescence of cardiac-specific proteins: c cTNT (green) and α-actinin (red), d connexin-43 (green) and α-actinin (red), e MLC2v (green) and MLC2a (red), and f β-MHC (green) and α-MHC (red). Scale bar: 20 μm