(A) Schematic of the protocols for NSC transplantation and for detection and ablation of transplanted cells. NSCs derived from GFP.LUC- or TR6.GFP.LUC-Tg mice were transplanted into SCI model mice 1 week after injury. VPA was intraperitoneally administered every day for 1 week. Survival of transplanted cells and locomotor function of the mice were monitored weekly for 14 weeks. (B) Survival of transplanted cells was checked every week using a bioluminescence imaging system. 6 weeks after injury (5 weeks after transplantation), each mouse received 2 DT administrations. By the following week, LUC activity had completely disappeared in mice transplanted with TR6.GFP.LUC-NSCs (lower panel). (C) Sagittal sections from SCI model mice transplanted with GFP.LUC- and TR6.GFP.LUC-NSCs 2 weeks after DT injection. All transplanted cells were ablated with DT (lower panel). Scale bar: 1 mm. (D) Time course of the changes in BBB scores in SCI model mice. The hind limb function of mice that had undergone dual treatment with TR6.GFP.LUC-NSCs and VPA dropped drastically after DT administration (black line). *P < 0.0001 compared with GFP.LUC-NSC–transplanted, VPA-administered, and DT-injected SCI model mice (blue line) (repeated measures ANOVA). Data are mean ± SEM. VPA, n = 8; no treatment, n = 8. (E) Twelve weeks after injury, groups of SCI model mice received NMDA injections, as indicated, into the injury epicenter, to ablate local neurons in the gray matter (blue, black, and yellow lines with triangles). *P < 0.0001 compared with non-NMDA–injected mice in each group (blue, black, and yellow lines with circles) (repeated measures ANOVA). Data represent mean ± SEM.