Microfluidic Single-Cell Analysis of Transplanted Human Induced Pluripotent Stem Cell–Derived Cardiomyocytes After Acute Myocardial Infarction

Abstract

Background Human induced pluripotent stem cells (iPSCs) are attractive candidates for therapeutic use, with the potential to replace deficient cells and to improve functional recovery in injury or disease settings. Here we test the hypothesis that human iPSC-derived cardiomyocytes (iPSC-CMs) can secrete cytokines as a molecular basis to attenuate adverse cardiac remodeling after myocardial infarction (MI). Methods and Results Human iPSCs were generated from skin fibroblasts and differentiated in vitro using a small molecule based protocol. Troponin+ iPSC-CMs were confirmed by immunohistochemistry, quantitative PCR, fluorescence activated cell sorting (FACS), and electrophysiological measurements. Afterwards, 2×106 iPSC-CMs derived from a cell line transduced with a vector expressing firefly luciferase and GFP were transplanted into adult NOD/SCID mice with acute left anterior descending (LAD) ligation. Control animals received PBS injection. Bioluminescence imaging (BLI) showed limited engraftment upon transplantation into ischemic myocardium. However, magnetic resonance imaging (MRI) of animals transplanted with iPSC-CMs showed significant functional improvement and attenuated cardiac remodeling when compared to PBS-treated control animals at day 35 (Ejection fraction: 24.5±1.3 vs. 14.5±1.5%; P<0.05). To understand the underlying molecular mechanism, microfluidic single cell profiling of harvested iPSC-CMs, laser capture microdissection (LCM) of host myocardium, and in vitro ischemia stimulation were used to demonstrate that the iPSC-CMs could release significant levels of pro-angiogenic and anti-apoptotic factors in the ischemic microenvironment. Conclusions Transplantation of human iPSC-CMs into an acute mouse MI model can improve left ventricular function and attenuate cardiac remodeling. Because of limited engraftment, most of the effects are possibly explained by paracrine activity of these cells.

In Vivo Dynamic Metabolic Changes After Transplantation of Induced Pluripotent Stem Cells for Ischemic Injury

“…Recently, several studies have reported that iPSC-CMs provide functional benefit after myocardial infarction, although there has been no consensus about the protective mechanism induced by these differentiated cardiomyocytes (11). By using cardiac MRI and comparing with a nontreated control, Wu et al (12) found that iPSC-CMs promoted cardiac protection and attenuated cardiac remodeling after myocardial infarction, despite limited engraftment detected with bioluminescence imaging. In our present study, we found that the iPSC group and the iPSC-CM group showed a steady increase in 18 F-FDG accumulation during the 4-wk period whereas the ESC group showed a higher accumulation only in the earlier stage, indicating that iPSCs, especially iPSC-CMs, may produce a more stable therapeutic response than ESCs or ESC-CMs.…”

Generation of Human Pluripotent Stem Cell-derived Endothelial Cells and Their Therapeutic Utility

“…The survival rate of hESC-derived ECs injected into infarcted hearts was shown to be less than 10% at 1 week, and less than 1% at 8 weeks [33]. Similarly, hPSC-derived cardiomyocytes showed poor survival in ischemic hearts, usually disappearing within a month [34]. Even when cells were injected in a hindlimb ischemia model, the results were not much different.…”

Enhanced Therapeutic and Long-Term Dynamic Vascularization Effects of Human Pluripotent Stem Cell–Derived Endothelial Cells Encapsulated in a Nanomatrix Gel

“…The survival of hESC-ECs injected into ischemic hearts was not much different: < 10% of the injected cells survived at 1 week and 1% or less remained at 8 weeks 8 . hPSC-derived cardiomyocytes showed poor survival in ischemic hearts, with most of them disappearing usually within a month 9 . Similar trends were observed when cells were injected into a hindlimb ischemia model.…”