Fig. 9

PD-1 suppression in microglia hinders axon regeneration and inhibits functional recovery after SCI in vivo. A Images of GFAP (green) co-stained with axons (5-HT, magenta) in AAV-Con and AAV-sh-PD-1 groups at 28 dpi in vivo. Asterisks indicate the lesion site, scale bars: low magnification, 100 μm; high magnification, 20 μm. B Quantification of the percentage of 5-HT⁺ area in the area of the spinal cord segment spanning the lesion site in (A). All data are presented as the mean ± SEM, n = 3 mice per group, **p < 0.01. C Representative immunofluorescence images of GFAP (green) and NeuN (magenta) neurons in Z1-Z3 zones adjacent to central lesion site in AAV-Con and AAV-sh-PD-1 mice at 28 dpi in vivo. Scale bar: magnification, 100 μm. D Quantification of NeuN⁺ neurons in Z1_Z3 zones adjacent to lesion site in AAV-Con and AAV-sh-PD-1 groups in (C). All data are presented as the mean ± SEM, n = 3 mice per group, **p < 0.01; ***p < 0.001; ****p < 0.0001. E Representative images of footprint analysis in mice treated with AAV-Con or AAV-sh-PD-1 at 28 dpi in vivo. F–H Quantification of the stride length and width and paw rotation. All data are presented as the mean ± SEM, n = 8 mice per group, **p < 0.01; ***p < 0.001. I Locomotor function was evaluated by BMS at the indicated time points in mice treated with AAV-Con or AAV-sh-PD-1. All data were presented as the mean ± SEM, n = 8 mice per group, *p < 0.05; **p < 0.01; ****p < 0.0001