Fig. 5
Functional integration of transplanted iPSC-CM into the myocardium. a Representative bright field image of a ventricular heart slice (left picture) with retained eGFP-positive iPSC-CM (right picture) 7 days after injection of 2 × 0.5 × 106 day 16 iPSC-CM. Left scale bar 1 mm, right scale bar 100 μm. The positions of the stimulation electrode (SE) and the recordings in host tissue and iPSC-CM are marked. b The quality of electrical integration of day 14 iPSC-CM, day 16 iPSC-CM, and native host cardiomyocytes assessed by the maximal stimulation frequency without conduction block. c Representative action potentials of a host cardiomyocyte and transplanted iPSC-CM. d Action potential properties of transplanted day 14 iPSC-CM (n = 6), day 16 iPSC-CM (n = 8), and host cardiomyocytes (n = 8). MDP maximal diastolic potential, Vmax maximal upstroke velocity, APD50 action potential duration at 50% of repolarization, APD90 action potential duration at 90% of repolarization. e Statistical analyses of action potential properties. Statistical analysis were performed using one-way ANOVA with post-test for host vs. iPSC-CM and Student’s t test for day 14 vs. day 16 iPSC-CM