Fig. 2

Myelin debris phagocytosis was reduced in MSR1 KO macrophages after spinal cord injury. a IF staining of the macrophage marker F4/80 (red) and the myelin marker MBP (green) in the damage areas of the MSR1 WT and KO groups at day 7 post SCI. Nuclei were counterstained with DAPI (blue). Scale bar = 200 μm. b–c Quantification of F4/80+ macrophages and myelin-laden macrophages in the lesion site at day 7 post injury (n = 3 per group, values are the mean ± SD, NS indicates no significance, **p < 0.01, two-tailed Student’s t tests). d Microscopic images of Oil Red O staining of the lesion sites at day 7 post injury in the MSR1 WT and KO groups. Scale bar = 500 μm. e Statistical analysis of the Oil Red O-stained areas in the MSR1 WT and KO groups (n = 3 per group, values are the mean ± SD, **p < 0.01, two-tailed Student’s t tests). f Transmission electron microscopy images of foamy macrophages in the lesion sites of the MSR1 WT and KO mice on day 7 post injury. Red arrows indicate degrading myelin debris, and white arrows indicate lipid droplets. Scale bars = 5 μm. g–h Numbers of myelin debris and lipid droplets in macrophages of the MSR1 WT mice on day 7 post injury (n = 3 per group, values are the means ± SD, **p < 0.01, two-tailed Student’s t tests)