Fig. 7
From: The breaking and making of healthy adult human skeletal muscle in vivo
Macrophage pseudopodia infiltrate necrotic tissue. Transmission electron microscopy of biopsies obtained from regenerating human skeletal muscle 7 days post injury. a is the lowest magnification, with b–d increasing in magnification and the area shown outlined by the white dashed line box in the preceding image. Damaged fibres were observed adjacent to completely intact fibres (evident from the preserved striated sarcomere pattern clearly visible in the bottom left corner of image c). Within the damaged fibre, necrotic tissue can be seen to fill the wider zone and is followed by cell-dense regions. The asterisk (a–c) indicates the nucleus of a putative macrophage, situated at the mouth of the necrotic zone with its pseudopodia (white arrows) extending deep into the necrotic tissue (c, d). a–c Scale bars, 10 μm. d 1 μm