Fig. 5

Virus-mediated delivery of Type III-NRG1 restores the number of NRG1-positive puncta and increases the size of motor neuron soma in SOD1^G93A mice. (a–c) Representative images for the lumbar motor neurons of SOD1^G93A mice injected GFP (a) or Type III-NRG1 (b, c) encoding AAV. The lumbar spinal cord sections were stained with antibodies for NRG1 (red) and ChAT (blue). Bar: 50 μm. (d, e) Quantification for the average number of NRG1-positive puncta (d) or VAChT-positive C-boutons (e) per motor neuron soma. Sixty motor neurons from GFP- or Type III-NRG1-injected symptomatic SOD1^G93A mice (n = 3 each) were analyzed for NRG1-positive puncta. The bars indicate averages for both groups. ***: p < 0.001, unpaired t-test. (f) Cumulative probability plot for the size of motor neuron soma. Sixty VAChT-positive lumbar motor neurons from SOD1^G93A injected with AAV-GFP (black) or AAV-Type III-NRG1 (red) were analyzed for the surface area of soma (n = 3 per each group). Non-statistical significance among two groups, Kolmogorov-Smirnov test. (g–j) Representative images for the lumbar spinal cord sections of SOD1^G93A mice injected with AAV-GFP (g, i) or AAV-Type III-NRG1 (h, j) stained with antibodies for GFAP (g, h) or Iba1 (i, j). Bar: 50 μm