Abstract

Tri-lineage cardiac cell therapy of hiPSCs: a pre-clinical study

Ye Lei, Principal Investigator, National Heart Research Institute Singapore/ National Heart Centre Singapore

Human induced pluripotent stem cells (hiPSCs) have attracted great interest for therapeutic application because of their ability to generate a broad range of patient-matched, clinically relevant cell types. Cardiomyocytes (CMs), endothelial cells (ECs) and smooth muscle cells (SMCs) differentiated from hiPSCs could be useful for patients with heart disease for autologous cellular therapy, for disease modeling and for testing new drugs in vitro. A new CM differentiation protocol was developed1. It yields a high percentage of CMs differentiated from hiPSCs that are reprogrammed not only from dermal fibroblasts, but also from blood mononuclear cells1. Next, a remarkably more efficient hiPSC-EC differentiation protocol that incorporates a three-dimensional (3D) fibrin scaffold was developed2. With this protocol, up to 45% of the differentiated hiPSCs assumed an EC phenotype, and after purification, greater than 95% of the cells displayed the EC phenotype (based on CD31 and CD144 expression). The hiPSC-ECs continued to display EC characteristics for 4 weeks in vitro, which is approximately twice as long as previously observed. The functional impact of intramyocardial transplantation of tri-lineage cardiac cells (hiPSC-Ms, hiPSC-ECs, and hiPSC-SMCs) was investigated in an immune-suppressed porcine heart model of ischemia reperfusion (I/R)3. hiPSC-ECs and hiPSC-SMCs were detected in vascular structures and hiPSC-CMs were found integrated into the myocardium and exhibited organized sarcomeric structure. Tri-lineage of cardiac cell transplantation resulted in significant improvements in infarct size, myocardial apoptosis, arteriole density, LV function, and cardiac metabolism without evidence for adverse effects. Large-scale label-free quantitative proteomics studies identified proteins that were associated with muscle contraction, embryo and muscle development and regeneration in pig heart after tri-lineage transplantation. This large animal model results encourage furt