https://www.selleckchem.com/products/pu-h71.html Here, we describe a method for the isolation of intact cardiomyocytes from fresh or frozen human myocardium or fresh mouse hearts and the quantification of multinucleation, cardiomyocyte size, cell cycle activity, and total cardiomyocyte count per heart. We generalize this fixation-digestion method by isolating cells from a variety of mouse organs, including the liver, lung, and thymus.Human induced pluripotent stem cells (hiPSCs) are among the most promising tools for regenerative myocardial therapy and in vitro modeling of cardiac disease; however, their full potential cannot be met without robust methods for differentiating them into cardiac-lineage cells. Here, we present novel protocols for generating hiPSC-derived cardiomyocytes (CMs), endothelial cells (ECs), and smooth muscle cells (SMCs) and for assembling them into a patch of human cardiac muscle (hCMP). The differentiation protocols can be completed in just a few weeks and are substantially more efficient than conventional methods, while the hCMP fabrication procedure produces a patch of clinically relevant size and incorporates a simple method for maturing the engineered tissue via mechanical stimulation. We also describe how the patch can be evaluated in a large-animal (swine) model of myocardial injury.Engineered cardiac tissues hold tremendous promise for in vitro drug discovery, studies of heart development and disease, and therapeutic applications. Here, we describe a versatile "frame-hydrogel" methodology to generate engineered cardiac tissues with highly mature functional properties. This methodology has been successfully utilized with a variety of cell sources (neonatal rat ventricular myocytes, human and mouse pluripotent stem cell-derived cardiomyocytes) to generate tissues with diverse 3D geometries (patch, bundle, network) and levels of structural and functional anisotropy. Maturation of such engineered cardiac tissues is rapidly achieved witho