Figure 8

Examination of induction of apoptosis. Brains were harvested at 2 days (A-C) or 1 month (D-F) and subjected to terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) analysis. Representative images of sections taken from (A) uninjured animals, (B) traumatic brain injury (TBI) animals and (C) TBI animals that received trans-retinoic acid (RA)-primed mesenchymal stem cells (MSC). Evaluation of apoptosis induction one month following TBI is shown in (D) uninjured (E) TBI animals and (F) TBI animals that received RA-primed MSC. Insert in E shows higher power image of TUNEL+ nuclei. Production of chondroitin sulfate proteoglycan (CSPG), glial fibrillary acidic protein (GFAP) or brain derived neurotropic factor (BDNF) in (G) unprimed MSC and (H-J) RA-primed MSC cultured for 7 days in vitro. (H) Staining for expression of CSPG (green) in cells not expressing GFAP (red) in RA-primed MSC. (I) Co-expression of CSPG (green) and GFAP (red) in some RA-primed MSC. (J) Expression of BDNF (green) and GFAP (red) in RA-primed MSC. (K-M) Evaluation of CSPG and BDNF in RA-primed MSC in vivo following TBI. (K) Evaluation of MSC products in sections of brains harvested at 2 days post transplantation of carboxyfluorescein succinimidyl ester (CFSE)-tagged MSC in regions near the injury site, CFSE-positive MSC (green) and CSPG (red). (J) Cells positive for CSPG and diamidino-2-phenylindole (DAPI) and (M) cells positive for CFSE (green) and BDNF (red) also seen in regions near the injury site. (A-M) DAPI nuclear stain (blue).