Fig. 3

Morphological characterization of CNS-resident myeloid cells following Igf-1r genetic ablation. To assess the morphology of CNS resident microglia (brain, spinal cord) and leptomeningeal BAMs in IGF-1R^{KO−tdTomato} (n = 4 mice) compared to IGF-1R^{WT−tdTomato} (n = 4 mice), we conducted three sets of analyses (Sholl analysis, skeletal analysis and fractal-lacunarity analysis – described in the method section). A Representative pictures of microglia from the brain of IGF-1R^{KO−tdTomato} and IGF-1R^{WT−tdTomato} mice and B quantification of number of branches per cell (p = 0.0001), fractal dimension (p = 0.0006), ending radius (p < 0.0001) of brain microglia (unpaired t test with Welch’s correction, approximative n° of cells analysed per group: IGF-1R^{KO−tdTomato} (n = 84) IGF-1R^{WT−tdTomato} (n = 71)). C Representative pictures of microglia morphology from the spinal cord of IGF-1R^{KO−tdTomato} and IGF-1R^{WT−tdTomato} mice and D quantification of number of branches per cell (p = 0.498), fractal dimension (p = 0.406), ending radius (p = 0.034) of spinal cord microglia (unpaired t test with Welch’s correction, approximative n° of cells analysed per group: IGF-1R^{KO−tdTomato} (n = 75) IGF-1R^{WT−tdTomato} (n = 66)). E Representative pictures of BAMs from the spinal cord leptomeninges of IGF-1R^{KO−tdTomato} and IGF-1R^{WT−tdTomato} mice and F quantification number of branches per cell (p = 0.034), fractal dimension (p = 0.760), ending radius (p = 0.049) of spinal cord BAMs (unpaired t test with Welch’s correction, approximative n. of cells analysed per group: IGF-1R^{KO−tdTomato} (n = 78) IGF-1R^{WT−tdTomato} (n = 91)). All values are presented as mean ± SEM. Asterisks indicate significant differences (∗ p < 0.05, ∗  ∗ p < 0.01 and ∗  ∗  ∗ p < 0.001, ∗  ∗  ∗  ∗ p < 0.0001)