Comparative assessment of different approaches for obtaining terminally differentiated cell lines

The study of pathogenesis of muscle disorders needs an appropriate cell model. In the field of muscle research, there is no general cell line considered standard for studying muscular and neuromuscular diseases. Most cell lines are incapable of differentiation into a muscle lineage exhibiting morphological and physiological properties of mature muscle cells and can hardly be genetically modified. The goal of our study was to find an informative cell model of muscle differentiation suitable for examination of muscular pathogenesis in vitro. We assayed cultured human mesenchymal stem cells (MSCs), mature murine muscle fibers, and primary murine satellite cells. It was shown that MSCs had very low capacity for myogenic differentiation; they were able to differentiate only in the presence of C2C12 cells. Lentiviral transduction had a toxic effect in primary myofiber cultures, and positively transduced cells were unable to respond to electrical stimulation, i.e., were functionally inactive. Satellite cells proved to be the most appropriate cell model, since they were easily transduced with lentiviruses and rapidly formed myotubes in the differentiation medima. Functional analysis of induced myotubes showed their ability to react to electrical and chemical stimulation. The patch-clump technique showed the presence of potassium and calcium channels. Collectively, the results show that cultured satellite cells are the most promising cell line for further experiments to explore molecular pathways in muscle pathologies.