Fig. 7. Primary myoblast cultures grown in FCS-20 for 2-3 days. Myoblasts are positive for desmin, whereas the muscle fibroblasts are negative (A). All cells stain positive for vimentin (B), and myoblasts, but not fibroblasts, are positive for myosin II heavy-chain (C). Nuclei are stained with DAPI. Bars, 50 µm.