Fig. 15

Overview of the regeneration of injured adult human skeletal myofibres. Upon injury, myofibres undergo necrosis, resulting in loss of the sarcolemma and removal of necrotic tissue by macrophages. The basement membrane, which is preserved, also acts as a scaffold for activated satellite cells to adhere to while they differentiate and fuse to form myotubes. Macrophages are also present in these zones. All the myotubes within a basement membrane tube eventually fuse with each other to form a single myofibre, which also forms a new basement membrane, resulting in a shedding of the original basement membrane. At 30 days post injury, the regenerating myofibres are still smaller than pre-injury and activated satellite cells are frequent on their surface