Foot-Print Free Generation of Cardiomyocytes from Somatic Cells

Objectives: The reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) offers an auspicious possibility to repair or replace missing or defective cells in the adult body. In contrast to viral vector-based generation of iPSCs, synthetic RNA-based modifications enable a foot-print free generation of cells and prevent the induction of mutagenesis. Thus, the cells obtained from these iPSCs offer a multitude of application possibilities in the field of tissue engineering. Here, we examined the generation of iPSCs using self-replicating RNA and performed differentiation experiments into cardiomyocytes.

Methods: A single transfection of human somatic cells was performed with 0.5 µg self-replicating RNA encoding reprogramming factors and green fluorescent protein. After 20 days, the differentiation of iPSCs into cardiomyocytes was performed. The obtained cells were analyzed using fluorescence microscopy, RT-qPCR, and flow cytometry.

Results: The first iPSC colonies were detected after 7 days. The expression of pluripotent stem cell-specific markers was evaluated. The treatment of iPSCs for 10 days with a differentiation medium resulted in generation of beating cardiomyocytes.

Conclusion: Using self-replicating RNA encoding transcription factors, autologous cardiomyocytes can be generated without genomic integration. These cells represent a promising cell source for repair of infarcted myocardium.