Title: Efficient human pluripotent stem cell derivation of left ventricle-like cardiomyocytes with matured properties: Can we use them to treat heart failure?

Abstract

Decreased left ventricle (LV) function caused by genetic mutations or injury often leads to debilitating and fatal cardiovascular disease. LV-cardiomyocytes are, therefore, a potentially valuable therapeutical target. Human pluripotent stem cell derived cardiomyocytes(hPSC-CMs) generated using current protocols are neither homogenous nor mature, which reduces their utility. Here we exploited cardiac development knowledge to devise a LV-cardiomyocyte differentiation protocol from hPSCs. Correct mesoderm patterning and retinoic acid pathway blocking were essential to generate near-homogenous hPSC-LV-CMs. As expected, hPSC-LV-CMs transit via first heart field progenitors and display typical ventricular action potentials. Unexpectedly,hPSCLV-CMs exhibit increased metabolism,reduced proliferation and improved cytoarchitecture and functional maturity compared to age-matched cardiomyocytes generated using the standard WNT-ON/WNT-OFF protocol. Of note was the calcium response to sarcoplasmic reticulum specific inhibitors (ryanodine and thapsigargin), which showed that hPSC-LV-CMs have more appropriate drug-responses. This increase in maturity is also observed in engineered heart tissues (EHTs) made from hPSC-LV-CMs, which are better organised, produce higher force andhave a slower beating ratebut can be paced to physiological levels. This demonstrates themechanical load induced maturity exerted by the EHTs was additive rather than transformative. Together, we show that hPSC-LV-CMs with mature properties can be rapidly obtained (in 20 days), even without exposure to reported maturation regimes. These cells are, therefore, a suitable model to study LV development and disease and will likely enable more faithful LVspecific cardiotoxicity screens. Moreover, this work opens the possibility of like-for-like cell replacement therapy becoming an accessible treatment for heart failure patients. British Heart Foundation (BHFFS/12/37/29516; RM/17/1/33377), Wellcome Trust (210987/Z/18/Z), Medical Research Council (MR/R017050/01;MR/X50287X/1), LifeArc (LifeArc-Crick Translation Fund) and Francis Crick Institute (FC001157).

Biography

Andreia was awarded her PhD from University of Aberdeen and in her PhD used stem cells to study pancreas development. She then moved to the University of Cambridge for a Post Doc with Professor Roger Perdersen, where she researched mesoderm specification using embryos and stem cells. Later she was awarded a BHF intermediate fellowship to study heart-chamber specification in Sir Jim Smith’s laboratory at the NIMR. After a 2 year career break, she was awarded a Wellcome Trust Career re-entry fellowship to continue her work on heart-chamber development at the Francis Crick Institute. Her experience includes human stem cells research and embryology. Her work has led to the submission of two patents arising from human stem cell studies. Andreia has collaborators in Europe and the USA. She is now trying to commercialise her left ventricle cardiomyocyte model for pharma use and her team is working in both academic and translational projects.