TY - JOUR
T1 - Phospholamban as a crucial determinant of the inotropic response of human pluripotent stem cell-derived ventricular cardiomyocytes and engineered 3-dimensional tissue constructs
AU - Chen, Gaopeng
AU - Li, Sen
AU - Karakikes, Ioannis
AU - Ren, Lihuan
AU - Zi-Ying Chow, Maggie
AU - Chopra, Anant
AU - Keung, Wendy
AU - Yan, Bin
AU - Chan, Camie W.Y.
AU - Costa, Kevin D.
AU - Kong, Chi Wing
AU - Hajjar, Roger J.
AU - Chen, Christopher S.
AU - Li, Ronald A.
N1 - Publisher Copyright:
© 2014 American Heart Association, Inc.
PY - 2015/2/28
Y1 - 2015/2/28
N2 - Background - Human (h) embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) serve as a potential unlimited ex vivo source of cardiomyocytes (CMs). However, a well-accepted roadblock has been their immature phenotype. hESC/iPSC-derived ventricular (v) CMs and their engineered cardiac microtissues (hvCMTs) similarly displayed positive chronotropic but null inotropic responses to β-adrenergic stimulation. Given that phospholamban (PLB) is robustly present in adult but poorly expressed in hESC/iPSC-vCMs and its defined biological role in β-adrenergic signaling, we investigated the functional consequences of PLB expression in hESC/iPSC-vCMs and hvCMTs. Methods and Results - First, we confirmed that PLB protein was differentially expressed in hESC (HES2, H9)- and iPSC-derived and adult vCMs. We then transduced hES2-vCMs with the recombinant adenoviruses (Ad) Ad-PLB or Ad-S16E-PLB to overexpress wild-type PLB or the pseudophosphorylated point-mutated variant, respectively. As anticipated from the inhibitory effect of unphosphorylated PLB on sarco/endoplasmic reticulum Ca 2+ -ATPase, Ad-PLB transduction significantly attenuated electrically evoked Ca 2+ transient amplitude and prolonged the 50% decay time. Importantly, Ad-PLB-transduced hES2-vCMs uniquely responded to isoproterenol. Ad-S16E-PLB-transduced hES2-vCMs displayed an intermediate phenotype. The same trends were observed with H9- and iPSC-vCMs. Directionally, similar results were also seen with Ad-PLB-transduced and Ad-S16E-transduced hvCMTs. However, Ad-PLB altered neither the global transcriptome nor I Ca,L, implicating a PLB-specific effect. Conclusions - Engineered upregulation of PLB expression in hESC/iPSC-vCMs restores a positive inotropic response to β-adrenergic stimulation. These results not only provide a better mechanistic understanding of the immaturity of hESC/iPSC-vCMs but will also lead to improved disease models and transplantable prototypes with adult-like physiological responses.
AB - Background - Human (h) embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSCs) serve as a potential unlimited ex vivo source of cardiomyocytes (CMs). However, a well-accepted roadblock has been their immature phenotype. hESC/iPSC-derived ventricular (v) CMs and their engineered cardiac microtissues (hvCMTs) similarly displayed positive chronotropic but null inotropic responses to β-adrenergic stimulation. Given that phospholamban (PLB) is robustly present in adult but poorly expressed in hESC/iPSC-vCMs and its defined biological role in β-adrenergic signaling, we investigated the functional consequences of PLB expression in hESC/iPSC-vCMs and hvCMTs. Methods and Results - First, we confirmed that PLB protein was differentially expressed in hESC (HES2, H9)- and iPSC-derived and adult vCMs. We then transduced hES2-vCMs with the recombinant adenoviruses (Ad) Ad-PLB or Ad-S16E-PLB to overexpress wild-type PLB or the pseudophosphorylated point-mutated variant, respectively. As anticipated from the inhibitory effect of unphosphorylated PLB on sarco/endoplasmic reticulum Ca 2+ -ATPase, Ad-PLB transduction significantly attenuated electrically evoked Ca 2+ transient amplitude and prolonged the 50% decay time. Importantly, Ad-PLB-transduced hES2-vCMs uniquely responded to isoproterenol. Ad-S16E-PLB-transduced hES2-vCMs displayed an intermediate phenotype. The same trends were observed with H9- and iPSC-vCMs. Directionally, similar results were also seen with Ad-PLB-transduced and Ad-S16E-transduced hvCMTs. However, Ad-PLB altered neither the global transcriptome nor I Ca,L, implicating a PLB-specific effect. Conclusions - Engineered upregulation of PLB expression in hESC/iPSC-vCMs restores a positive inotropic response to β-adrenergic stimulation. These results not only provide a better mechanistic understanding of the immaturity of hESC/iPSC-vCMs but will also lead to improved disease models and transplantable prototypes with adult-like physiological responses.
KW - adrenergic effects
KW - phospholamban
KW - pluripotent stem cells
KW - tissues
UR - http://www.scopus.com/inward/record.url?scp=84923852701&partnerID=8YFLogxK
U2 - 10.1161/CIRCEP.114.002049
DO - 10.1161/CIRCEP.114.002049
M3 - Article
C2 - 25504561
AN - SCOPUS:84923852701
SN - 1941-3149
VL - 8
SP - 193
EP - 202
JO - Circulation: Arrhythmia and Electrophysiology
JF - Circulation: Arrhythmia and Electrophysiology
IS - 1
ER -