Immunohistochemical analysis of the transplanted umbilical cord mesenchymal stem cells (UC MSCs). No neuronal or glial differentiation was observed from the transplanted UC MSCs as seen by the lack of co-localization between the UC MSCs (blue) with NeuN (red) or GFAP (green), respectively (A). A decreased significant difference in the amount of surviving transplanted cells was observed in low-passage UC MSCs, when compared to high-passage UC MSCs (B). A significant increase in GFAP optical densitometry around the transplant site was observed in the R6/2 mice that received transplantation of low-passage UC MSCs (C). GFAP, glial fibrillary acidic protein; NeuN, neuronal nuclei.