Figure 8. Distinct skeletal muscle macrophage morphologies.

A. Representative image from the vastus lateralis muscle showing a macrophage with classic morphology. Described in other tissues, the outstretched processes of resting macrophages are thought to surveil the local environment (Olah et al., 2011; Durafourt et al., 2012). B. A CD11b+/CD206+ macrophage (top) stretching out toward a second CD11b+/CD206− macrophage (bottom). C. Round or amoeboid shaped macrophage. In other tissues, this morphology is thought to be indicative of activation and the production of inflammatory cytokines (Olah et al., 2011; Durafourt et al., 2012). A–C) Scale bars = 20 μm. D. Macrophages surround a damaged skeletal muscle fiber (indicated by the presence of central nuclei). Scale bars = 50 μm. A–D) Images were acquired as Z stacks using a 40x objective and cropped to enlarge. CD11b (green), CD206 (red), cell nuclei/DAPI (blue).