Introduction:
Both human embryonic stem cell-derived cardiomyocytes (ESC-CMs) and human induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs) can serve as an unlimited cell source for cardiac regenerative therapy. However, the functional equivalency of both approaches has not been previously reported. Here we performed head-to-head comparison on the beneficial effects of ESC-CM and iPSC-CMs in restoring cardiac function in a rat myocardial infarction (MI) model.
Methods & Results:
Human ESCs and iPSCs were differentiated into cardiomyocytes using small molecules. FACS analysis confirmed ~85% and ~83% of cells differentiated from ESCs and iPSCs, respectively, were positive for cardiac troponin T, and immunofluorescence staining demonstrated that ESC-CMs and iPSC-CMs have striated sarcomeric structure (Figure A-B). Both ESC-CMs and iPSC-CMs displayed similar maturity for calcium handling (transient amplitude: ΔF/F
0
= 3.8±0.3; time to peak: ~200 ms; 50% transient duration: ~400 ms). qRT-PCR showed that ESC-CMs and iPSC-CMs expressed CASQ2, GJA5, KCNJ2, KCNJ5, MYH6, MYH7, and SCN5A at comparable levels to human fetal heart tissue. Next, ESC-CMs and iPSC-CMs were injected into the left ventricular free wall of infarcted hearts (adult nude rats; n=14, 10, respectively). Cardiac function was assessed by MRI one month post cell injection and the hearts were harvested and stained for human cardiac markers. Both ESC-CMs and iPSC-CMs could engraft in ischemic rat hearts (Figure C). Comprehensive functional analysis with small animal magnetic resonance imaging (MRI), echocardiography, and pressure-volume loop analysis are underway.
Conclusion:
We set out to perform head to head comparison for the first time that iPSC-CMs may facilitate cardiac repair at comparable levels to ESC-CMs. Unlike allogeneic ESC-CM therapy, autologous iPSC-CMs could be used to overcome immune rejection for cardiac cell transplantation in the future.
Neurotrophin‐3 contributes to benefits of human embryonic stem cell‐derived cardiovascular progenitor cells against reperfused myocardial infarction
