Fig. 2

Myoblasts at under 20 divisions differentiate efficiently and are not senescent. A total of 12 separate primary cell lines were cultured to under 21 divisions. a Dot-plot showing the percentage of primary human myoblasts fused into myotubes for 12 separate cell cultures, with an average fusion index calculated as 95.14% ± 4.28. b Representative images of myotubes positive for myosin heavy chain (in red), a marker of differentiation. Scale bar = 100 μm. c Over 80% of the flask is covered and no obvious signs of cell death are observed. Scale bar = 100 μm.