SummaryWhen pluripotency factors are removed, embryonic stem cells (ESCs) undergo spontaneous differentiation, which, among other lineages, also gives rise to cardiac sublineages, including chamber cardiomyocytes and pacemaker cells. Such heterogeneity complicates the use of ESC-derived heart cells in therapeutic and diagnostic applications. We sought to direct ESCs to differentiate specifically into cardiac pacemaker cells by overexpressing a transcription factor critical for embryonic patterning of the native cardiac pacemaker (the sinoatrial node). Overexpression of SHOX2 during ESC differentiation upregulated the pacemaker gene program, resulting in enhanced automaticity in vitro and induced biological pacing upon transplantation in vivo. The accentuated automaticity is accompanied by temporally evolving changes in the effectors and regulators of Wnt signaling. Our findings provide a strategy for enriching the cardiac pacemaker cell population from ESCs.
These results suggest that ELF-EMFs tuned at Ca2+-ICR could be used to drive cardiac-specific differentiation in adult cardiac progenitor cells without any pharmacological or genetic manipulation of the cells that will be used for therapeutic purposes.
The successful isolation and ex vivo expansion of resident cardiac stem/progenitor cells from human heart biopsies has allowed us to study their biological characteristics and their applications in therapeutic approaches for the repair of ischemic/infarcted heart, the preparation of tissue-engineered cardiac grafts and, possibly, the design of cellular kits for drug screening applications. From the first publication of the original method in 2004, several adjustments and slight changes have been introduced to optimize and adjust the procedure to the evolving experimental and translational needs. Moreover, due to the wide applicability of such a method (which is based on the exploitation of intrinsic functional properties of cells with regenerative properties that are present in most tissues), the key steps of this procedure have been used to derive several kinds of tissue-specific adult stem cells for preclinical or clinical purposes.In order to define the original procedure, complete with the up-to-date modifications introduced through the years, an exhaustive description of the current protocol is performed in this chapter, with particular attention in highlighting critical steps and troubleshoots. The procedure described here consists of modular steps, that could be employed to derive cells from any kind of tissue biopsy, and needs to be considered the gold standard of all the so-called "explant methods" or "cardiosphere methods," and it represents a milestone in the clinical translation of autologous cell therapy.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.