Fig 3. Fluorescent imaging.

(A) Vital fluorescent dye staining with CM-Dil did not affect the viability and morphology of the MSCs. (B) Control group transplanted with unstained MSCs showed no fluorescent signals both on the whole brain surface and in slices. Fluorescent signals on the surface of the MCA territory or cortical region of slices were stronger in the D1 group than in the D4 or D7 groups. However, fluorescent signals on the striatal region of slices were weaker in the D1 group than in the D4 or D7 groups. (C) The quantification of MSCs by photon emission (photons/s/cm²/sr) representing fluorescence intensity also showed similar results (*P < 0.05) (n = 5 for each group). (D) The MSCs stained with CM-DiI were dominantly detected at the cortex in the D1 group and at striatum in the D4 and D7 groups. CM-DiI indicates chloromethylbenzamido-1,1'-dioctadecyl-3,3,3',3'-tetramethylindocarbocyanine perchlorate; MSCs, mesenchymal stem cells; MCA, middle cerebral artery.