Transplanted Adult Neural Stem Cells Express Sonic Hedgehog In Vivo and Suppress White Matter Neuroinflammation after Experimental Traumatic Brain Injury

Figure 3

Induced genetic in vivo labeling of host cells expressing Shh after NSC transplantation into mice with traumatic brain injury (TBI). Timeline (a) and diagram (b) for experiments in Shh^CreERT2;R26tdTomato host mice. Two weeks after TBI or sham surgery mice received an injection into the lateral ventricle (LV) of either NSCs constitutively expressing green fluorescent protein (NSC-GFP cells), or vehicle. To induce genetic labeling of host cells expressing Shh (Shh-Tom cells), TMX was administered on days 2 and 3 after injection of NSCs/vehicle. Mice were perfused 4 weeks after TBI/sham surgery. (c–h) Coronal sections showing Shh-Tom labeling (red) with DAPI nuclear stain (blue) and transplanted NSC-GFP cells (green). Shh-Tom labeling in cell bodies ((c–d) arrows) and axons (e–h). Inset (c) shows neuronal morphology of Shh-Tom cells (arrows) in the striatum with example from upper arrow. Injections occasionally missed the LV resulting in NCS-GFP transplantation into the adjacent tissue and serve to show the potential to elaborate extensive processes is dependent on the transplant site (d). NSC-GFP cells transplanted directly into the LV grew as spheres (e, f) and were often observed nestled in the choroid plexus (cp), or extended only short processes when adhered to the walls of the LV (g, h). Scale bars = 1 mm (b), 200 μm (c), 100 μm (d–g), 50 μm (h). Representative images are shown from analysis of a cohort of sham + NSC-GFP (), TBI + vehicle (), and TBI + NSC-GFP () mice.