Figure 1
Increased GDNF expression in CNS tissue following systemic injection of AAV9-GDNF. (a) Histological analysis of GDNF expression in CNS tissue sections revealed GDNF staining in the cortex, septum and hippocampus, as well as the spinal cord gray matter in rats injected with AAV9-GDNF but not those injected with AAV9(−) control virus. (b) Quantification of GDNF expression in various tissues from both WT and SOD1 rats by ELISA confirmed that after injections of AAV9-GDNF, GDNF levels were increased in the brain, spinal cord and muscle relative to AAV9(−)-injected controls but not in the kidney. There were no detectable levels of GDNF expression in the serum of any of the groups. (c) Immunostaining for ChAT in the ventral horn of the cervical spinal cord revealed significantly greater numbers of (d) total ChAT+ cells and (e) ChAT+ cells >700 μm per section in AAV9-GDNF-treated SOD1 rats relative to AAV9(−) controls. (f) Average ChAT+ cell size was not significantly different. Sample size: n=4 per group and the same animals were used for each assay. *P<0.05, unpaired, two-tailed t-test; error bars=s.e.m. Scale bars a, b: 500 μm; c: 100 μm. ELISA, enzyme-linked immunosorbent assay; FL, forelimb; HL, hindlimb; SC, spinal cord.
