In the neuroregeneration study, the engrafted NTN-c17.2 cells survived the grafting procedure well and expressed high levels of the NTN protein in vivo. A-F, Double immunohistochemistry with anti-β-Gal (LacZ, in red) or NTN (red) antibody (no crossreaction with GDNF) and anti-Nestin (green) showed cells expressing the NTN protein in the NTN-c17.2 engrafted striatum 4.5 d, 30 d and 120 d postgrafting; however, with time, the cells differentiated, and the number of cells declined and almost no nestin protein was detected 30 d and 120 d postgrafting. G, Quantification of the number of LacZ+ Nestin+, and NTN+ Nestin+ cells. The number of immune-positive cells were counted in 7 serial sections through the striatum. Values represent the mean ± SEM. *#P < 0.01. The striatum grafted with NTN-c17.2 or Mock-c17.2 cells at 4.5 d were compared with 30 d and 120 d postgrafting, which was determined by one-way ANOVA. Scale bars: 250 μm.