Predicting mesenchymal stem cells potential for cardiac repair by clinical indicators and inducing differentiation to cardiomyocytes in vitro by mimicry of in vivo microenvironment

Patient-specific factors critically influence the therapeutic potential of bone marrow-derived mesenchymal stem cells (BM-MSCs) for cardiac regeneration. In this work, we identify lymphocyte count as a key clinical predictor of BM-MSC proliferative capacity, with coronary artery disease significantly delaying expansion in patients undergoing cardiac surgery. Thus, we established cell selection criteria for patient-derived MSCs for further differentiation into cardiomyocytes. To overcome the limitations of MSCs in cardiac differentiation, we developed a novel protocol using conditioned medium mimicking patient-specific in vivo conditions from iPSC-derived cardiomyocytes (iPSC-CM). This approach successfully generated functional cardiomyocytes from patient-specific BM-MSCs, as evidenced by spontaneous calcium transitions, structural maturation, and electrophysiological activity. Our results provide a unique protocol for inducing MSC differentiation for cell therapy from patient selection to patient-specific personalized preparation as a differentiation strategy.