Engineered Heart Slices for Studies of Human Pluripotent Stem Cell-Derived Cardiomyocytes

cardiac tissue engineering;electrophysiology;Biomedical Engineering

Blazeski, AdrianaTomaselli, Gordon F ;

Johns Hopkins University

关键词: cardiac tissue engineering;    electrophysiology;    Biomedical Engineering;   

Others  :  https://jscholarship.library.jhu.edu/bitstream/handle/1774.2/60962/Blazeski_Adriana_Thesis.docx?sequence=2&isAllowed=y

瑞士|英语

来源: JOHNS HOPKINS DSpace Repository

【 摘 要 】

While cardiomyocytes derived from human pluripotent stem cells (hPSC-CMs) represent a promising population for in vitro cardiac studies, drug testing, and disease modeling, they are structurally and functionally immature relative to their adult counterparts. As a result, a range of cardiac tissue engineering strategies have emerged in order to advance the maturation of these hPSC-CMs. One promising approach is to incorporate the complex biochemical and structural cues of the myocardial extracellular matrix (ECM) to promote the organization and cellular signaling required for cellular maturation. We employed this strategy and repopulated thin sections of decellularized porcine left ventricles with hPSC-CMs to make engineered heart slices (EHS). EHS organized hPSC-CMs into multicellular, aligned bundles that deformed the ECM during contractions and showed positive inotropic response to isoproterenol. EHS could be paced over a range of cycle lengths, exhibited anisotropic conduction of action potentials, and could maintain electrophysiological functionality for more than 200 days. Further, EHS supported the culture of a variety of cell types, including wild-type cardiomyocytes derived from human induced pluripotent stem cells (hiPSC-CMs), hiPSC-CMs from lines with monogenic diseases (LQT2), and cardiomyocytes derived from human embryonic stem cells (hESC-CMs). We evaluated EHS by comparing them to monolayers of hPSC-CMs and found that they promote cellular elongation and sarcomere organization in individual CMs and exhibit less triangulated action potentials. We applied several ion channel modulating drugs to both preparations and found that EHS are less sensitive to HERG channel block at high pacing rates, respond to larger doses of IK1-blocker than monolayers, and are more responsive to block of ICa,L than monolayers, suggesting that the EHS promotes electrophysiological maturation. Finally, we demonstrated the utility of EHS in disease modeling by developing a model of arrhythmogenic cardiomyopathy (AC), a disease affecting cell-cell adhesion. While monolayers of disease hiPSC-CMs could not be maintained in culture and peeled off when the disease phenotype was exacerbated by the application of adipogenic stimuli, EHS maintained their function and could be used to study attributes of the disease. Thus, they represent a promising platform for studying how cellular level changes translate into aberrant multi-cellular electrical activity in AC.This thesis presents a novel preparation, the EHS, for culturing hPSC-CMs in a tissue-like environment that is suitable for long-term drug studies and disease modeling.