Project description:Cardiac maturation is an important developmental phase where there are profound biological and functional changes after birth in mammals. Herein, we use our profiling of human heart maturation in vivo to identify key drivers of maturation in our human cardiac organoid (hCO) model. After screening of various metabolism modulating factors, we established a directed maturation (DM) protocol to induce mature cardiac expression and compared the proteomic changes to our original serum free (SF) protocol. In this dataset, we compared 4 replicates of DM to 4 replicates of SF derived cardiac organoids using global DIA-MS/MS.
Project description:Human induced pluripotent stem cell (hiPSC)-derived cardiovascular cells are promising cell source for cell therapy to repair the heart. Cardiac microtissue consisted of cardiomyocytes and fibroblast cells exhibited much better physiological functions. How different cardiovascular cell types interact and evolve in 3D microenvironment is unknown. In this study, we performed single-cell transcriptome profiling of hiPSC-derived mini-cardiac organoid consisted of cardiomyocytes, endothelial cells and smooth muscle cells. Our analysis showed that cardiac fibroblasts emerged spontaneously in 3D microenvironment which in turn facilitated the maturation of cardiomyocytes. HiPSC-derived cardiomyocytes, endothelial cells and smooth muscle cells assembled into mini-cardiac organoid in collagen-matrigel after 2 weeks. Single-cell study uncovered significant cell fate shift and improvement in cardiomyocyte maturation status upon-multilineage co-culture. Ligand-receptor analysis identified DLK1-Notch signaling to be one of the most upregulated pathways in the fibroblast population. Modulate the activity of DLK1-Notch signaling affected the assembly of the mini-cardiac organoid and the expression of immune regulatory genes. Interestingly, transplantation of trilineage mini-cardiac organoid into a rat model of myocardial infarction leads to significant improvement of cardiac function. Collectively, our single-cell analysis of mini-cardiac organoid provided rich information about cell fate dynamics and multilineage cross-talks occurred in the 3D microenvironment, which bring new insight on the molecular mechanism that promotes cardiomyocyte maturation and heart repair.
Project description:Cardiac maturation is an important developmental phase where there are profound biological and functional changes after birth in mammals. Herein, we use our profiling of human heart maturation in vivo to identify key drivers of maturation in our human cardiac organoid (hCO) model. After screening of various metabolism modulating factors, we established a directed maturation protocol to induce mature cardiac expression. We next compared directed maturation treatment to electrical pacing using phosphoproteomics in order to assess the similarities in the induction of maturation. The electrical pacing protocol utilized a custom platform, where we added Heart-Dyno inserts into C-pace system in 24-well plates enabling 120 bpm pacing for 5 minutes without causing toxicity. In this dataset, we compared 3 replicates of CTRL (our original serum free organoid protocol), electrical pacing (the standard protocol for maturation of cardiac stem cells), and directed maturation protocol (DM, new protocol) through phosphoproteomics.
Project description:Crosstalk between cardiac cells is critical during heart development but its role in organ maturation is still largely uncharacterised. Here, we show that endothelial cells increas the force of contraction and enhance the expression of mature sarcomeric proteins and extracellular matrix (ECM) components in human pluripotent stem cell derived cardiac organoids (hCO). Endothelial cells regulate cardiac maturation and function both directly through secretion of ECM molecules and indirectly via paracrine signaling. Laminin α5, an endothelial enriched ECM protein, was identified as a key regulator of cardiac maturation and contractility in vitro. In vivo loss-of-function studies in mice confirmed that Lama5 was required for myocardial expansion during heart development in vivo. In addition, paracrine PDGF signaling was identified as a mediator of increased ECM deposition and cardiac contractility in hCO. This study uncovers matrix regulatory functions of endothelial cells governing cardiac maturation and highlights the importance of multicellularity for organoid models.
Project description:Reactivating the human epicardium post-cardiac injury holds promise for cardiac tissue regeneration. Despite successful differentiation protocols yielding pure, self-renewing epicardial cells from induced pluripotent stem cells (iPSCs), these cells maintain an embryonic, proliferative state, impeding adult epicardial reactivation investigation. We introduce an optimized method that employs mammalian target of rapamycin (mTOR) signaling inhibition in embryonic epicardium, inducing a quiescent state that enhances multi-step epicardial maturation. This yields functionally mature epicardium, valuable for modeling adult epicardial reactivation. Furthermore, we assess cardiac organoids with cardiomyocytes and mature epicardium, probing molecular mechanisms governing epicardial quiescence during cardiac maturation. Our results highlight iPSC-derived mature epicardium's potential in investigating adult epicardial reactivation, pivotal for effective cardiac regeneration. Additionally, the cardiac organoid model offers insight into intricate cardiomyocyte-epicardium interactions in cardiac development and regeneration.
Project description:Rationale: Human pluripotent stem cells-derived cardiomyocytes (hPSC-CMs) exhibit the properties of fetal CMs, which limit their applications. Various methods have been used to promote maturation of hPSC-CMs; however, there is a lack of an unbiased and comprehensive method for accurate benchmarking of hPSC-CM maturation.
Objective: We aim to develop an unbiased proteomics method integrating high-throughput top-down targeted proteomics and bottom-up global proteomics for accurate and comprehensive assessment of hPSC-CM maturation.
Methods and Results: Utilizing hPSC-CMs from early- and late-stage two-dimensional monolayer culture and three-dimensional engineered cardiac tissue, we demonstrated high reproducibility and reliability of the top-down proteomics method, which enabled simultaneous quantification of contractile protein isoform expressions and their PTMs. This method allowed for the detection of known maturation-associated contractile protein alterations, and for the first time, identified contractile protein PTMs as promising new markers of maturation. By employing a global proteomics strategy, we identified candidate maturation markers important for sarcomere organization, cardiac excitability, and Ca2+ homeostasis; and validated these markers in the developing mouse cardiac ventricles.
Conclusions: We established an unbiased proteomics method that can provide accurate and specific benchmarking of hPSC-CM maturation, and identified new markers of maturation. Furthermore, this integrated proteomics strategy laid a strong foundation for uncovering molecular basis underlying cardiac development and disease using hPSC-CMs.
Project description:Single-cell analysis of human iPSC-derived multi-lineage mini-cardiac organoid reveals molecular pathways to promote cardiomyocyte maturation and heart repair
Project description:Cardiac maturation is an important developmental phase where there are profound biological and functional changes after birth in mammals. Herein, we use our profiling of human heart maturation in vivo to identify key drivers of maturation in our human cardiac organoid (hCO) model. In this dataset, we exemplified the applicability of our mature organoids in modelling cardiac contraction. Three calsequesterin-2 (CASQ2) knock out (-/-) hCO lines were generated to demonstrate the effect of sarcoplasmic reticulum Ca2+ leakiness on contraction. In this dataset, we evaluate the proteomic remodelling induced by CASQ2 (-/-, n=3) versus CTRL mature hCOs (n=1).
Project description:Crosstalk between cardiac cells is critical during heart development but its role in organ maturation is still largely uncharacterised. Here, we show that endothelial cells increase the force of contraction and enhance the expression of mature sarcomeric proteins and extracellular matrix (ECM) components in human pluripotent stem cell derived cardiac organoids (hCO). Endothelial cells regulate cardiac maturation and function both directly through secretion of ECM molecules and indirectly via paracrine signaling. Laminin α5, an endothelial enriched ECM protein, was identified as a key regulator of cardiac maturation and contractility in vitro. In vivo loss-of-function studies in mice confirmed that Lama5 was required for myocardial expansion during heart development in vivo. In addition, paracrine PDGF signaling was identified as a mediator of increased ECM deposition and cardiac contractility in hCO. This study uncovers matrix regulatory functions of endothelial cells governing cardiac maturation and highlights the importance of multicellularity for organoid models.
Project description:Self-organisation and coordinated morphogenesis of multiple cardiac lineages is essential for the development and function of the heart1-3. However, the absence of a human in vitro model that mimics the basic lineage architecture of the heart hinders research into developmental mechanisms and congenital defects4. Here, we describe the establishment of a reliable, lineage-controlled and high-throughput cardiac organoid platform. We show that cardiac mesoderm derived from human pluripotent stem cells robustly self-organises and differentiates into cardiomyocytes forming a cavity. Co-differentiation of cardiomyocytes and endothelial cells from cardiac mesoderm within these structures is required to form a separate endothelial layer. As in vivo, the epicardium engulfs these cardiac organoids, migrates into the cardiomyocyte layer and differentiates. We use this model to demonstrate that cardiac cavity formation is controlled by a mesodermal WNT-BMP signalling axis. Disruption of one of the key BMP targets in cardiac mesoderm, the transcription factor HAND1, interferes with cavity formation, which is consistent with its role in early heart tube and left chamber development5. Thus, the cardiac organoid platform represents a powerful resource for the quantitative and mechanistic analysis of early human cardiogenesis and defects that are otherwise inaccessible. Beyond understanding congenital heart disease, cardiac organoids provide a foundation for future translational research into human cardiac disorders.