We heart cultured hearts. A comparative review of methodologies for targeted differentiation and maintenance of cardiomyocytes derived from pluripotent and multipotent stem cells.

Human cell lines, including disease cell lines are often superior to routine animal models for the purposes of rapid and safe assessment of the effects of different agents that may modulate myocardial functioning under physiological and pathological conditions. There are several currently existing methodologies for derivation of cardiomyocyte-like cells by targeted differentiation from pluripotent cells and by reprogramming/transdifferentiation from other types of cells (multipotent progenitors, somatic cells, etc). The present paper reviews the potential sources of cells capable of differentiation along the cardiomyocyte lineage; the existing methodologies for targeted differentiation, outlining the specificities of each method; and the markers for differentiation along the mesodermal and the cardiogenic lineage. The yield of robustly beating cells expressing cardio-specific proteins derived by any of the existing methods, however, still rarely exceeds 70-90 %, even with the newly developed approaches for increasing the differentiation capacity. There still is significant variance in the results obtained by different research groups and even between different experiments carried out in the same laboratory, with the same type of cells and same general type of protocol. Derivation of new lines of human pluripotent and multipotent stem cells according to standardised protocols and in completely defined; xeno-free conditions may increase the reliability and reproducibility of research and speed up the development of potential clinical applications. [ABSTRACT FROM AUTHOR]