Geometry-dependent functional changes in iPSC-derived cardiomyocytes probed by functional imaging and RNA sequencing.
Human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CM) are a promising platform for cardiac studies in vitro, and possibly for tissue repair in humans. However, hiPSC-CM cells tend to retain morphology, metabolism, patterns of gene expression, and electrophysiology similar to that of embryonic cardiomyocytes. We grew hiPSC-CM in patterned islands of different sizes and shapes, and measured the effect of island geometry on action potential waveform and calcium dynamics using optical recordings of voltage and calcium from 970 islands of different sizes. hiPSC-CM in larger islands showed electrical and calcium dynamics indicative of greater functional maturity. We then compared transcriptional signatures of the small and large islands against a developmental time course of cardiac differentiation. Although island size had little effect on expression of most genes whose levels differed between hiPSC-CM and adult primary CM, we identified a subset of genes for which island size drove the majority (58%) of the changes associated with functional maturation. Finally, we patterned hiPSC-CM on islands with a variety of shapes to probe the relative contributions of soluble factors, electrical coupling, and direct cell-cell contacts to the functional maturation. Collectively, our data show that optical electrophysiology is a powerful tool for assaying hiPSC-CM maturation, and that island size powerfully drives activation of a subset of genes involved in cardiac maturation.
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America.
Christopher A
CA
Werley
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America.
Miao-Ping
MP
Chien
Broad Institute, Cambridge, Massachusetts, United States of America.
Jellert
J
Gaublomme
Broad Institute, Cambridge, Massachusetts, United States of America.
Karthik
K
Shekhar
Department of Biology, MIT, Cambridge, Massachusetts, United States of America.|Department of Biological Engineering, MIT, Cambridge, Massachusetts, United States of America.|David H. Koch Institute for Integrative Cancer Research, MIT, Cambridge, Massachusetts, United States of America.
Vincent
V
Butty
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America.
B Alexander
BA
Yi
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America.
Joel M
JM
Kralj
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America.
Blox
BB
Bloxham
Department of Biology, MIT, Cambridge, Massachusetts, United States of America.|Department of Biological Engineering, MIT, Cambridge, Massachusetts, United States of America.
Laurie A
LA
Boyer
Broad Institute, Cambridge, Massachusetts, United States of America.|Department of Biology, MIT, Cambridge, Massachusetts, United States of America.|Howard Hughes Medical Institute, Cambridge, Massachusetts, United States of America.
Aviv
A
Regev
Department of Chemistry and Chemical Biology, Harvard University, Cambridge, Massachusetts, United States of America.|Howard Hughes Medical Institute, Cambridge, Massachusetts, United States of America.|Department of Physics, Harvard University, Cambridge, Massachusetts, United States of America.
Adam E
0000-0002-8699-2404
AE
Cohen
D000200:Action Potentials / Q000502:physiology; D002118:Calcium / Q000378:metabolism; D002454:Cell Differentiation / Q000235:genetics; D002478:Cells, Cultured; D055724:Electrophysiological Phenomena / Q000502:physiology; D015870:Gene Expression / Q000235:genetics; D006801:Humans; D057026:Induced Pluripotent Stem Cells / Q000166:cytology* / Q000378:metabolism / Q000502:physiology*; D032383:Myocytes, Cardiac / Q000378:metabolism / Q000502:physiology*; D017423:Sequence Analysis, RNA / Q000379:methods; D014158:Transcription, Genetic / Q000235:genetics
D002118:Calcium