Figure 9

Evaluation of mesenchymal stem cells (MSC) 3 months post transplantation. (A) Results represent the average +/- SD for cell counts from brains of uninjured (n = 8) and traumatic brain injury (TBI) (n = 8) rats. Statistically significant comparisons (*P < 0.05) for expression of type III beta tubulin (Tuj1) or neuron specific nuclear protein (NEUN) in brain sections from uninjured compared to TBI rats. (B) Diagram of locations viewed in images B-I (red shaded circle) and location of site of fluid percussion injury (black arrow). (C) Brain section from TBI rats sacrificed 3 months after transplantation of carboxyfluorescein succinimidyl ester (CFSE)+ CD133+ABCG2+CXCR4+ MSC showing cells in the cortex and hippocampus near the injury site. White arrows indicate CFSE-positive MSC (green). (D) Image of area outlined in box of figure B, CFSE (green) and Tuj1 (red). (E-J) Examination of transplanted MSC showed that most cells had elongated, CFSE (green), DAPI (blue). (E) These cells were positive for expression of human major histocompatibility complex class I (MHC 1) (red). (F) CFSE+ cells in the hippocampus at 3 months had reduced levels of CXCR4 staining. (F and G) In some regions of the hippocampus, networks of MSC showed interconnections between cells and many cells in these clusters were (G and H) tyrosine hydroxylase (TH)-positive. (I) Human MHC I expression by cells in J and (J) a small portion of MSC were positive for expression of the astrocyte marker GFAP, and (H) had a more complex morphology with multiple branched cell processes. (D-J) Diamidino-2-phenylindole (DAPI) nuclear stain (blue).