BS21 Building a pipeline for large-scale phenotypic drug screen with hescs-cardiomyocytes – lessons learnt

The adult mammalian heart is the least regenerative organ in the body. Up to ~ a billion cardiomyocytes are lost after a heart attack. Recent advances to replace lost muscle (primary remuscularization) and recover cardiac function relied strongly on the relative accessibility of human embryonic stem cells (hESCs)-derived cardiomyocytes (CMs). To successfully regenerate the injured heart, hESCs-CMs must survive, proliferate, mature and integrate in vivo. However, the long-term behaviour of hESCs-CMs in vivo remains unpredictable, compounded by its pro-arrhythmic nature. Thus, we adapted a commonplace practice in drug development e.g. large-scale phenotypic drug screening, to systematically perturb each regulatory pathway in hESCs-CM to determine its composite behaviour in vitro in both injury and non-injury settings. We first developed a robust pipeline to enable small-scale phenotypic drug screening of hESCs-Cardiomyocytes with clinically applicable compounds such as beta-blockers, myosin inhibitors. Our outputs include fluorescence-labelled Ca²⁺ kinetics, subcellular live-cell imaging. However, we found that the hESC-CMs were highly variable with different maturation and contractility rates. To optimize the signal-to-noise ratio in our readouts, we aim to utilise the real-world data generated by our large-scale phenotypic drug screen to develop an in silico perturbation model of hESC-CMs. Ultimately, this data science-intensive approach would enable a better prediction of hESC-CMs behaviour in vitro and in vivo with wide-ranging applications in both cardiac regeneration and cardiovascular medicine specific to heart failure patients.