TY - JOUR
T1 - Elastomer-grafted iPSC-derived micro heart muscles to investigate effects of mechanical loading on physiology
AU - Guo, Jingxuan
AU - Simmons, Daniel W.
AU - Ramahdita, Ghiska
AU - Munsell, Mary K.
AU - Oguntuyo, Kasoorelope
AU - Kandalaft, Brennan
AU - Rios, Brandon
AU - Pear, Missy
AU - Schuftan, David
AU - Jiang, Huanzhu
AU - Lake, Spencer P.
AU - Genin, Guy M.
AU - Huebsch, Nathaniel
N1 - Funding Information:
This work was supported by startup funds from the McKelvey School of Engineering at Washington University in Saint Louis, the American Heart Association (19CDA34730016 to N.H.), and the National Science Foundation Center for Engineering Mechanobiology (CMMI: 15-48571 to N.H., D.W.S., and G.G.). We thank Dr. Alexandre J. S. Ribeiro (US Food and Drug Administration) for technical advice on surface modification, the ninhydrin assay, and the TFM analysis tool, and Dr. Srikanth Singamaneni and Dr. Patricia Weisensee (Washington University Department of Mechanical Engineering and Materials Science) for helpful discussions on surface chemistry. We thank Michael Vahey (Washington University, Department of Biomedical Engineering) for allowing us to use the confocal microscope for sarcomere analysis.
Publisher Copyright:
© 2020 American Chemical Society.
PY - 2021/7/12
Y1 - 2021/7/12
N2 - Mechanical loading plays a critical role in cardiac pathophysiology. Engineered heart tissues derived from human induced pluripotent stem cells (iPSCs) allow rigorous investigations of the molecular and pathophysiological consequences of mechanical cues. However, many engineered heart muscle models have complex fabrication processes and require large cell numbers, making it difficult to use them together with iPSC-derived cardiomyocytes to study the influence of mechanical loading on pharmacology and genotype-phenotype relationships. To address this challenge, simple and scalable iPSC-derived micro-heart-muscle arrays (μHM) have been developed. "Dog-bone-shaped"molds define the boundary conditions for tissue formation. Here, we extend the μHM model by forming these tissues on elastomeric substrates with stiffnesses spanning from 5 to 30 kPa. Tissue assembly was achieved by covalently grafting fibronectin to the substrate. Compared to μHM formed on plastic, elastomer-grafted μHM exhibited a similar gross morphology, sarcomere assembly, and tissue alignment. When these tissues were formed on substrates with different elasticity, we observed marked shifts in contractility. Increased contractility was correlated with increases in calcium flux and a slight increase in cell size. This afterload-enhanced μHM system enables mechanical control of μHM and real-time tissue traction force microscopy for cardiac physiology measurements, providing a dynamic tool for studying pathophysiology and pharmacology.
AB - Mechanical loading plays a critical role in cardiac pathophysiology. Engineered heart tissues derived from human induced pluripotent stem cells (iPSCs) allow rigorous investigations of the molecular and pathophysiological consequences of mechanical cues. However, many engineered heart muscle models have complex fabrication processes and require large cell numbers, making it difficult to use them together with iPSC-derived cardiomyocytes to study the influence of mechanical loading on pharmacology and genotype-phenotype relationships. To address this challenge, simple and scalable iPSC-derived micro-heart-muscle arrays (μHM) have been developed. "Dog-bone-shaped"molds define the boundary conditions for tissue formation. Here, we extend the μHM model by forming these tissues on elastomeric substrates with stiffnesses spanning from 5 to 30 kPa. Tissue assembly was achieved by covalently grafting fibronectin to the substrate. Compared to μHM formed on plastic, elastomer-grafted μHM exhibited a similar gross morphology, sarcomere assembly, and tissue alignment. When these tissues were formed on substrates with different elasticity, we observed marked shifts in contractility. Increased contractility was correlated with increases in calcium flux and a slight increase in cell size. This afterload-enhanced μHM system enables mechanical control of μHM and real-time tissue traction force microscopy for cardiac physiology measurements, providing a dynamic tool for studying pathophysiology and pharmacology.
KW - Afterload
KW - Calcium dynamics
KW - Cardiac contractility
KW - Elastomer modification
KW - Stem cells
UR - http://www.scopus.com/inward/record.url?scp=85096051027&partnerID=8YFLogxK
U2 - 10.1021/acsbiomaterials.0c00318
DO - 10.1021/acsbiomaterials.0c00318
M3 - Article
C2 - 34275296
AN - SCOPUS:85096051027
SN - 2373-9878
VL - 7
SP - 2973
EP - 2989
JO - ACS Biomaterials Science and Engineering
JF - ACS Biomaterials Science and Engineering
IS - 7
ER -